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H A R R I S C O U N T Y

OFFICE OF THE COUNTY ENGINEER 1001 Preston, 5

Floor

Houston, Texas 77002

(713) 755-5370

July 9, 2019

Honorable County Judge

& Commissioners Court

SUBJECT: Recommendation by the County Engineer that Commissioners Court

Authorize and Adopt Regulations of Harris County, Texas for

Floodplain Management and Regulations of Harris County, Texas for

the Approval and Acceptance of Infrastructure in Response to the

National Oceanic and Atmospheric Administration (NOAA) Atlas 14

Information Release

Dear Court Members:

Transmitted for your consideration are the Regulations of Harris County, Texas for

Floodplain Management and the Regulations of Harris County, Texas for the Approval

and Acceptance of Infrastructure. These regulations have been revised based on the

knowledge that the effective Flood Insurance Rate Maps (FIRMs) do not accurately

define flood risks because they are based on rainfall information that has since been

updated following the release of information in the National Oceanic Atmospheric

Administration (NOAA) Atlas 14 precipitation frequency analysis. If approved, these

regulations will supersede the previous documents amended on December 5, 2017 and

December 18, 2018 respectively. These documents have been prepared in

consultation with various engineering and development organizations in Harris County,

as well as representatives of the Court Members. The County Attorney’s Office has

reviewed and approved these documents.

The major revisions are as follows:

x Requires mitigation for reduction in floodplain storage or conveyance capacity

within the 500-year floodplain.

x Requires certification indicating the floodplain status of buildable areas of a plat

x Updates Intensity-Duration-Frequency (IDF) curves based on Atlas 14 rainfall

data

x Increases the minimum storage rate from 0.65 ac-ft/ac to 0.75 ac-ft/ac for

detention ponds that outfall to storm sewers

x Adds language to clarify and improve enforcement actions

x Includes required updates due to the projected impacts of HB 3167

H A R R I S C O U N T Y

OFFICE OF THE COUNTY ENGINEER 1001 Preston, 5

Floor

Houston, Texas 77002

(713) 755-5370

SUBJECT: Summary of Changes to Harris County Floodplain and Infrastructure

Regulations in Response to NOAA Atlas 14 information Release

Summary of Changes:

Regulations of Harris County, Texas for Flood Plain Management:

Preface

x Added preface to illustrate reasoning behind these regulation changes

Section 2.03

x Added definition for “Administratively Complete”

Section 2.24

x Updated “Floodplain Mitigation” definition.

Section 2.33

x Removed “Subdivision” from “Manufactured Home Park” definition

Section 2.40

x Added definition of “Plan”

Section 2.45

x Removed “Substantial Damage” processes from “Substantial Improvement”

section, detailed Substantial Damage process added to the Regulations in

Section 5.01.

x Excluded demolition from the definition of “improvement”

Section 2.46

x Added definition of “Substantial Modification” – increase of impervious cover,

volume, peak discharge

Section 2.47

x Added definition of “Substantial Damage”

Section 2.49

x Added definition of “Vested Rights”

Section 4.02

x Added process to define a permit application as incomplete if an outstanding

violation exists on a property

Section 4.03

x Added a requirement to maintain drainage at all times

Section 4.04

x Updated requirements for permit application submittals

Section 4.05

x Updated determination of permit eligibility

Section 4.07

x Changed floodplain fill mitigation requirement from 100 to 500 year

x Added requirements for Manufactured Home Parks

2|HARRIS COUNTY ENGINEERING REGULATIONS SUMMARY

Section 4.09

x Removed “Term of Permits” sections requiring construction to begin within 180

days of permit issuance

Section 4.10

x Added “Vested Rights” definition and procedure for grandfathering projects.

Section 4.11

x Added procedure for vested rights determination

Section 5.01

x Added Substantial Damage definition and process for determining substantial

damage to a structure

Section 5.02

x Added a requirement to bring substantially damaged structures into compliance

with the Floodplain Management regulations

Section 5.03

x Added a process to issue Temporary Repair Permits pending the submittal of

final documents to include Proof of Loss statement detailing flood insurance

payment

Section 6.05

x Added a timeline to the procedure to revoke a permit

Regulations of Harris County, Texas for the Approval and Acceptance of

Infrastructure:

Preface

x Added preface to illustrate reasoning behind these regulation changes

Section 2.04

x Added definition of “Buildable Area”

Section 2.13A

x Added definition of “Floodplain Easement”

Section 2.24

x Added definition of “Residential Lot”

Section 2.28

x Added definition of “Substantial Modification”

Section 4.03

x Added requirement for Surveyor to delineate the floodplain on a plat and

establish a floodplain easement if necessary

Section 4.05

x Added that the plat will be promoted to Court upon approval fo the plat

application by the County Engineer

Section 4.06

x Added requirement for Surveyor to delineate the floodplain on a plat and

establish a floodplain easement if necessary

Section 4.07

x Added requirements for Floodplain Easements

3|HARRIS COUNTY ENGINEERING REGULATIONS SUMMARY

Section 4.08

x Added dedicatory language for Floodplain Easements

Section 4.09

x Added Alternate Planning Criteria

Section 5.06

x Added Supplemental Requirements to be included in plan submittals

Section 6.01

x Revised Drainage Policy to further detail street design requirements and

structural flooding protection requirements

Section 6.02

x Added rainfall intensity for storm sewer design to use Region 3 data

Section 6.03

x Updated storm sewer detention rate from 0.65 ac-ft/ac to 0.75,

Section 8.0

x Added requirement to provide physical markers to delineate any Floodplain

easements on properties

Section 12.03

x Added requirement for Roadside Signs

Section 15

x Added “Vested Rights” definition and procedure for grandfathering projects.

Table 7.3

x Updated number of bars in 10-inch concrete, minor correction of oversight from

previous update

Appendix G

x Updated to reference floodplain regulations for projects in 100 or 500 year

floodplains.

Appendix H

x Updated intensity duration curves and charts

REGULATIONS OF HARRIS COUNTY, TEXAS

FOR FLOODPLAIN MANAGEMENT

ADOPTED 5 JUNE 2007

EFFECTIVE 18 JUNE 2007

AMENDED 8 NOVEMBER 2011

AMENDED 5 DECEMBER 2017

EFFECTIVE 1 JANUARY 2018

AMENDED 9 JULY 2019

EFFECTIVE 9 JULY 2019

JOHN R. BLOUNT, P.E.

COUNTY ENGINEER

LOYD SMITH, P.E.

ASSISTANT COUNTY ENGINEER

PREFACE

This Regulation is being revised and approved based on

the knowledge that the effective Flood Insurance Rate

Maps (FIRMs) do not accurately define flood risks because

they are based on rainfall information that has since been

updated.

The National Oceanic and Atmospheric Administration’s

(NOAA) Atlas 14 precipitation frequency analysis

indicates that the updated 100-year frequency rainfall

approximates the current 500-year frequency rainfall.

Therefore, this Regulation has been adjusted to reflect

that fact.

Upon issuance of the new FIRMs using updated rainfall

data as part of the MAAPnext project undertaken by the

Harris County Flood Control District and FEMA, and

concurrent with their adoption, this Regulation may

require adjustments to more accurately regulate flood

risks.

REGULATIONS OF HARRIS COUNTY, TEXAS

FOR FLOODPLAIN MANAGEMENT

PART 1 - PRELIMINARY PROVISIONS

SECTION 1.01 - AUTHORITY

The Regulations of Harris County, Texas for Floodplain

Management (“Regulations”) are adopted by the

Commissioners' Court of Harris County, Texas, acting in its

capacity as the governing body of Harris County and the

Harris County Flood Control District. The authority of

Harris County to adopt these Regulations and for the

contents hereof is derived from the following statutes:

Texas Local Government Code Section 240.901, as

amended; Texas Transportation Code Sections 251.001 -

251.059 and Sections 254.001 - 254.019, as amended; the

Harris County Road Law, as amended; and the Flood

Control and Insurance Act, Subchapter I of Chapter 16 of

the Texas Water Code, as amended. These Regulations may

be amended at any time by a majority of Commissioners'

Court as approved by the appropriate federal authorities.

SECTION 1.02 - AREA COVERED BY REGULATIONS

These Regulations apply in all unincorporated areas of

Harris County, Texas.

SECTION 1.03 - PURPOSE

The purpose of these Regulations is to provide land use

controls necessary to qualify unincorporated areas of

Harris County for flood insurance under requirements of

the National Flood Insurance Act of 1968, as amended, to

protect human life and health; to avoid increasing flood

levels or flood hazards or creating new flood hazard areas;

to minimize public and private losses due to flooding; to

reduce the need for expenditures of public money for flood

control projects; to reduce the need for rescue and relief

efforts associated with flooding; to prevent or minimize

damage to public facilities and utilities and to aid the public

in determining if a property is in a potential flood area.

SECTION 1.04 - CONSTRUCTION OF REGULATIONS

These Regulations are to be construed liberally to

accomplish their purpose and to assure that Harris County

complies with all State and Federal Laws.

SECTION 1.05 - ABROGATION AND GREATER

RESTRICTIONS

The Regulations of Harris County, Texas for Floodplain

Management heretofore existing are repealed. However,

such prior regulations shall continue to apply to

construction pursuant to permits issued prior to the

effective date of the Regulations. Except as herein above

expressly provided, these Regulations are not intended to

repeal, abrogate, or impair any existing laws, regulations,

easements, covenants, or deed restrictions. Where these

Regulations and other legal requirements conflict or

overlap, whichever imposes the more stringent restrictions

shall prevail.

SECTION 1.06 - WARNING AND DISCLAIMER OF

LIABILITY

The degree of flood protection required by these

Regulations is considered reasonable for regulatory

purposes and is based on scientific and engineering

considerations. On occasion greater floods might occur,

and flood heights could be increased by man-made or

natural causes. These Regulations do not imply that any

area or the uses permitted within any area will be free from

flooding and flood damage. These Regulations shall not

create liability on the part of Harris County or any officer

or employee thereof for any flood damages that result from

reliance on these Regulations or any administrative

decision lawfully made thereunder. The granting of a

permit does not imply that the development can be insured

by Federal Flood Insurance.

SECTION 1.07 - FINDINGS OF FACT

It is hereby found by the Commissioners' Court of Harris

County that severe flooding has occurred in the past within

its jurisdiction and is likely to occur in the future, and that

damage to property occurs for many reasons including

flooding from the tidal waters of the Gulf of Mexico and

that the entire area within its jurisdiction is a rising-water

prone area.

SECTION 1.08 - BASIS FOR REGULATION

Harris County hereby adopts as the basis for Regulation the

Flood Insurance Study (FIS) and Flood Insurance Rate Map

(FIRM) adopted on June 18, 2007, by the Federal

Emergency Management Agency (FEMA) and any

subsequent amendments or revisions thereto. Harris

County hereby adopts as its regulatory floodways the

floodways shown on the said FIRM.

PART 2 - USE OF TERMS

SECTION 2.01 - ACCESSORY BUILDING

“Accessory building” means a structure which is

subordinate to, and the use of which is incidental to, that

of the principal structure or use on the same property.

SECTION 2.02 - ADMINISTRATOR

“Administrator” means the Federal Emergency

Management Agency Director.

SECTION 2.03 – ADMINISTRATIVELY COMPLETE

“Administratively Complete” means a completed permit

application that is submitted to the County Engineer along

with all required fees and includes all the required

documents or Plans listed on the Administratively

Complete Checklist provided on Harris County

Engineering – Permits website. An Administratively

Complete permit application is ready for technical review.

SECTION 2.04 - BASE FLOOD

“Base Flood” is the national standard on which the

floodplain management and insurance requirements of the

National Flood Insurance Program (NFIP) are based.

Special Flood Hazard Areas (SFHAs) are depicted on

Federal Emergency Management Agency (FEMA) Flood

Insurance Rate Maps (FIRMs) and are areas subject to

inundation by the base flood having a one-percent or

greater probability of being equaled or exceeded during

any given year (this is also known as a 1% or 100-year flood

event).

SECTION 2.05 - BASE FLOOD ELEVATION

“Base flood elevation” means the calculated elevation or

level above mean sea level that flood waters may reach

during the base flood.

SECTION 2.06 - BREAKAWAY WALL

“Breakaway wall” means a wall that is not part of the

structural support of the building and is intended through

its design and construction to collapse under specific

lateral loading forces, without causing damage to the

elevated portion of the building or supporting foundation

systems.

SECTION 2.07 - CERTIFICATE OF COMPLIANCE

“Certificate of Compliance” means a document issued by

the County Engineer indicating a site is in compliance with

the Regulations of Harris County, Texas for Floodplain

Management as of a specific date. The certificate may be

filed in the Real Property Records as outlined in Section

8.01 of these Regulations.

SECTION 2.08 - CERTIFICATE OF NON-COMPLIANCE

“Certificate of Non-Compliance” means a document issued

by the County Engineer indicating a site is not in

compliance with the Regulations of Harris County, Texas

for Floodplain Management as of a specific date. The

certificate also advises that legal action may be taken

against the property owner and that a request for denial of

flood insurance may be processed with the Federal

Emergency Management Agency (FEMA). This certificate

may be filed in the Real Property Records as outlined in

Section 8.01 of these Regulations.

SECTION 2.09 - COASTAL AREAS

“Coastal Areas” mean areas which border on bays or

estuaries or other waterways subject to tidal action which

are subject to possible flooding or increased flood levels

because of tidal action, hurricane surge or rising water due

to storms, hurricanes or tsunamis. A “coastal area” is not

necessarily in a “V” Zone. In cases where there is a

question as to whether an area is a coastal area, the County

Engineer shall refer to the Flood Insurance Study.

SECTION 2.10 – CONFORMING SUBDIVISION

“Conforming Subdivision” means a subdivision where the

lots are above the 1% or 100 year flood elevation and the

infrastructure (streets, building pads etc.) meet the

requirements of the “Regulations of Harris County, Texas

for the Approval and Acceptance of Infrastructure” as

adopted August 11, 2009 or previous additions where the

subdivisions meets the criteria for Extreme Event Analysis,

Relationship of Structures to Street, and Calculation of

Flow provisions of the 2009 regulations.

SECTION 2.11 - CONVEYANCE

“Conveyance” means the flow of water during the base

flood with a velocity that is greater than one foot per

second or a depth that is greater than one foot.

SECTION 2.12 - COUNTY ENGINEER

“County Engineer” means the holder of the statutory office

of County Engineer for Harris County or the employee

designated by the County Engineer to perform a task

required by these Regulations.

SECTION 2.13 - CRITICAL FACILITIES

“Critical Facilities” means those facilities essential to the

preservation of life and property, including, but not

limited to schools, nursing homes, hospitals, police, fire

and emergency response installations, facilities used for

the storage of critical records, and commercial

installations which produce, use or store hazardous

materials or hazardous waste as referenced in the most

recently amended Harris County Fire Code’s High-Hazard

Group (Group H) adopted from the International Fire

Code.

SECTION 2.14 - DEVELOPMENT

“Development” means any man-made change to improved

or unimproved real estate, including but not limited to

buildings or other structures, Substantial Improvements to

existing buildings or structures, mining, dredging, filling,

grading, paving, excavation or drilling operations or

storage of equipment or materials. Fences or fence-type

walls located within the floodplain are included within this

definition.

“Development” shall not include (1) routine maintenance

and routine repairs to existing structures; (2) residential

accessory buildings or structures not located in A or V

Zones with floor areas of less than one hundred fifty (150)

square feet; and (3) other insignificant activities including

the temporary storage of equipment or materials in the “X”

Zones.

SECTION 2.15 – DFIRM

“DFIRM” means a digital version of the Flood Insurance

Rate Map. DFIRMs may contain additional information not

normally available on the paper map.

SECTION 2.16 - DRAINAGE

“Drainage” means runoff that flows over land as a result

of precipitation. This shall include sheet flow, flow in

streets and flows which may concentrate in local drainage

systems with or without defined channels.

SECTION 2.17 - ELEVATION

“Elevation” means height above mean sea level. The North

American Vertical Datum (NAVD) of 1988 (2001 Adjusted)

shall be used. Any future studies changing the FIRM which

is referenced to a later re-leveling of the vertical control

system shall be used whenever a revised FIRM becomes

effective.

SECTION 2.18 - ELEVATION CERTIFICATE

“Elevation Certificate” means FEMA Form 81-31, February

13, 2006 or subsequent revisions used to show elevations

of real property in relation to base flood elevations.

SECTION 2.19 - EXISTING MANUFACTURED HOME PARK

“Existing manufactured home park” means a manufactured

home park for which the construction of facilities for

servicing the lot on which the manufactured homes are to

be affixed (including, at a minimum, the installation of

utilities, either final site grading or the pouring of concrete

pads, and the construction of streets) are completed before

the effective date of floodplain management regulations

adopted by Harris County on September 16, 1976.

SECTION 2.20 - EXPANSION

“Expansion” means an addition to an existing

development. Different types of “expansions” are treated

differently by these Regulations.

(a) “Expansion of a structure” means an addition

attached to, but outside of, either the vertical or

horizontal confines of the existing structure or

below the first floor level of a building elevated

on posts or piers, but which is not a “substantial

improvement” as defined by these Regulations.

(b) “Expansion of a manufactured home park” means

the making of any additional manufactured home

lots or spaces within an existing manufactured

home park, or on land adjoining an existing

manufactured home park.

park” means the preparation of additional sites by

the construction of facilities for servicing the lots

on which the manufactured homes are to be

affixed (including the installation of utilities,

either final site grading or pouring of concrete

pads, and the construction of streets).

SECTION 2.21 - FILLING

“Filling” means the placement of natural sands, dirt, soil

or rock above the natural grade to raise the elevation of the

ground. Fill may also include concrete, cement, soil

cement, brick or similar material as approved on a case-

by-case basis.

SECTION 2.22 - FLOOD INSURANCE RATE MAP

“Flood Insurance Rate Map” or “FIRM” means an official

map of a community on which the Federal Emergency

Management Agency has delineated the appropriate areas

of flood hazards, the 1 percent or 100-year flood elevations,

and the risk premium zones applicable to the County. In

these regulations this map shall be called “FIRM”. The map

is divided into zones which are used for setting regulatory

requirements. The type of permit, and the requirements of

the permit will vary depending on the zone in which a

property is located.

SECTION 2.23 - FLOOD INSURANCE STUDY

"Flood Insurance Study" means the official report

provided by the Federal Emergency Management Agency.

The report contains flood profiles and the water surface

elevation of the 1 percent and 0.2 percent or 100-year and

500-year flood.

SECTION 2.24 - FLOODPLAIN MITIGATION

“Floodplain Mitigation” means a hydraulically equivalent

volume of floodplain storage sufficient to offset a

reduction in floodplain storage or conveyance capacity of

the 0.2 percent or 500-year floodplain located outside a

coastal area.

SECTION 2.25 - FLOODPROOFING

“Floodproofing” means any structural and non-structural

additions, changes, or adjustments to properties and

structures which reduces or eliminates flood damages to

lands, water and sanitary facilities, other utilities,

structures, and contents of buildings.

SECTION 2.26 - FLOODWAY

“Floodway” means the channel of a river or other

watercourse and the adjacent land areas that must be

reserved to carry and discharge the base flood without

cumulatively increasing the water surface elevation more

than a designated height.

SECTION 2.27 - HABITABLE FLOOR

“Habitable Floor” means any floor of a building or

structure usable for sleeping, living, cooking, working,

recreation or any combination thereof. Bathrooms and

utility rooms are included in this definition, as are storage

areas greater than one hundred fifty (150) square feet in

size.

SECTION 2.28 - HIGHEST ADJACENT GRADE

“Highest Adjacent Grade”, as it applies to an elevation

certificate, means the highest natural elevation of the

ground prior to construction next to the proposed walls of

a structure.

SECTION 2.29 - LANDSCAPING

“Landscaping” means the placement of trees, shrubs, or

plants for the purpose of beautification.

SECTION 2.30 - LEVEE

“Levee” means a man-made or natural condition, usually

an earthen embankment or berm, that contains, controls,

restricts or diverts the flow of water.

SECTION 2.31 - LOWEST ADJACENT GRADE

”Lowest Adjacent Grade”, as it applies to an elevation

certificate, means the lowest elevation of the finished

grade immediately next to the structure.

SECTION 2.32 - MANUFACTURED HOME

“Manufactured home” means a structure, transportable in

one or more sections, which is built on a permanent chassis

and is designed for use with or without a permanent

foundation when connected to the required utilities. For

floodplain management purposes the term “manufactured

home” also includes recreational vehicles including those

that are roadworthy and licensed

, and other similar

vehicles placed on a site for greater than 180 consecutive

days.

SECTION 2.33 - MANUFACTURED HOME PARK

“Manufactured home park” means the entire parcel (or

contiguous parcels) of land, including the appurtenant

improvements, which has been improved so that it contains

two or more manufactured home lots available for the

placement thereon of manufactured homes for occupancy.

SECTION 2.34 - MEAN SEA LEVEL

“Mean Sea Level” means the average height of the surface

of the sea for all states of the tide as was established by the

United States Coastal and Geodetic Survey in 1929.

SECTION 2.35 - NATURAL GROUND

“Natural Ground” means the grade unaffected by

construction techniques such as fill, landscaping, or

berms.

SECTION 2.36 – NON-CONFORMING SUBDIVISION

A “Non-conforming Subdivision” means a subdivision or

parcel that does not meet the Extreme Event Analysis,

Relationship of Structures to Street, and Calculations of

Flow provisions found in the “Regulations of Harris

County, Texas for the Approval and Acceptance of

Infrastructure” as adopted August 11, 2009.

SECTION 2.37 - NORTH AMERICAN VERTICAL DATUM

(NAVD)

"North American Vertical Datum (NAVD)", as corrected in

1988 (2001 adjusted), is a vertical control used as a

reference for establishing varying elevations within the

floodplain. If a datum other than NAVD 88 is used then the

datum must be listed as the reference datum on the

applicable FIRM panel. If a datum other than NAVD 88 is

used, a conversion to NAVD 88 must be provided on the

Elevation Certificate.

SECTION 2.38 - PERMITS

“Permits” shall mean a permit as required by these

Regulations. A Class “I” Permit is issued for any

development that is located on a property where the

elevation of the ground is above the 1 percent or 100-year

elevation. A Class “II” Permit is issued for any

development that is located on a property where the

ground elevation is below the 1 percent or 100-year flood

elevation or subject to flooding as determined by these

Regulations.

All County and Harris County Flood Control District

projects shall have a signature block on the drawing, which

verifies compliance with these regulations. The executed

signature block acts as a permit for County and Harris

County Flood Control projects for the purpose of these

regulations.

SECTION 2.39 - PERSON

“Person” includes any individual or group of individuals,

corporation, partnership, association, or any other

organized group of persons, including State and Local

governments and agencies thereof.

SECTION 2.40 - PLAN

“Plan” shall mean development drawings or specifications,

preliminary subdivision drawings or specifications,

subdivision construction drawings or specifications, site

drawings or specifications, general drawings or

specifications, land development drawings, specifications,

or application or site development plan”

SECTION 2.41 - RECREATIONAL VEHICLE

“Recreational vehicle” means a vehicle that is: (1) Built on

a single chassis; (2) Four hundred square feet or less when

measured at the largest horizontal projections; (3)

Designed to be self-propelled or permanently towable and

(4) Designed primarily not for use as a permanent

dwelling but as temporary living quarters for

recreational, camping, travel, or seasonal use.

SECTION 2.42 - START OF DEVELOPMENT

“Start of Development” means either the first placement of

permanent construction of a structure on a site, such as the

pouring of a slab or footings, the installation of piles, or the

placement of a manufactured home on a foundation.

Included within this definition is grading and filling,

installation of streets or underground utilities and other

such development. A permit is required prior to the start

of any development.

SECTION 2.43 - STRUCTURE

“Structure” means a walled and/or roofed building or a gas

or liquid storage tank which is principally above ground. A

manufactured home on a permanent foundation is a

structure. The term includes a building, which is in the

course of construction, alteration or repair.

SECTION 2.44 - SUBDIVISION

“Subdivision” means a division of any tract of land into two

(2) or more parts for the purpose of laying out any

subdivision or any tract of land or any addition to the city,

or for laying out suburban lots or building lots, or any lots,

and streets, alleys or parts of other portions intended for

public use or the use of the purchasers or owners of lots

fronting thereon or adjacent thereto. A subdivision

includes re-subdivision (replat), but it does not include the

division of land in parcels or tracts of 10 acres or more and

not involving any new streets, alleys or easements of

access. This definition is based on current state statutes

and should the statutes be changed its new definition

would govern.

SECTION 2.45 - SUBSTANTIAL IMPROVEMENT

A “Substantial Improvement” means the repair,

reconstruction, or improvement of a structure, where the

cost of the said improvement equals or exceeds 50% of the

value of the structure either before the improvement is

started or, if the structure has been damaged and is being

restored, before the damage occurred. An improvement is

started when the first alteration, excluding demolition, of

any wall, ceiling, floor or other structural part of the

building commences, whether or not the alteration affects

the external dimensions of the structure. For purposes of

determining if an improvement is a substantial

improvement, the applicant for a permit must submit data

reflecting the value of the structure prior to being repaired,

improved or modified and the cost of the restoration,

improvement or modification. Costs shall include the value

paid for all labor and materials.

For the purpose of determining the value of the structure

before being repaired, reconstructed or improved, the

Harris County Appraisal District’s market value for the

structure will be used. If the applicant wishes to contest

this value an independent certified appraisal may be

submitted. Upon review and concurrence by the Harris

County Appraisal District, this appraised value for the

structure will be used for determining if the improvement

is substantial.

SECTION 2.46 – SUBSTANTIAL MODIFICATION

Substantial modification shall mean changes to the

approved Plans, plat, and/or drainage report or change of

use that will increase impervious cover, or the volume

and/or peak discharge of the stormwater runoff from

portions of, or the whole of the project or any other change

that would affect the volume or peak discharge of

stormwater runoff that would cause adverse impacts to off-

site properties.

SECTION 2.47 – SUBSTANTIAL DAMAGE

Substantial damage applies to a structure in a Special Flood

Hazard Area (SFHA), or 1% annual chance floodplain, for

damages of any origin sustained by the structure whereby

the cost of restoring the structure to its before damaged

condition would equal or exceed 50 percent of the market

value of the structure before the damage occurred.

SECTION 2.48 - UNINCORPORATED AREA

“Unincorporated area” means the area in Harris County,

Texas, that is not within an incorporated area of a city,

town, village, or within the jurisdiction of the Port of

Houston Authority Navigation District (being that area

within 2,500 feet of the thread of the Houston Ship Channel

that is eligible for limited purpose annexation pursuant to

Texas Local Government Code §43.136.)

SECTION 2.49 - VESTED RIGHTS

“Vested Right(s)” shall mean any rights accrued pursuant

to the Tex. Local Government Code, Chapter 245, or other

applicable vested rights law, which allow a person to

“freeze” or “vest” governmental regulations by filing an

Administratively Complete permit application with the

County Engineer.

SECTION 2.50 - ZONES

Zones on the Flood Insurance Rate Map have the following

meanings:

ZONE A: Areas of the base (1% or 100-year) flood

where base flood elevations have not been

determined.

ZONE AE: Areas of the base (1% or 100-year) flood

where base flood elevations have been

determined.

ZONE AH: Areas of the base (1% or 100-year) flood

where depths are between 1.0 and 3.0 feet;

and base flood elevations are shown.

ZONE AO: Areas of the base (1% or 100-year) flood

where depths are between 1.0 and 3.0 feet;

average depths of inundation are

determined.

ZONE A99: Areas inundated by the base (1% or 100-

year) flood to be protected by a Federal flood

protection system under construction; no

base flood elevations are determined.

ZONE V: Areas of coastal flooding with velocity (wave

action); base (1% or 100-year) flood

elevations not determined.

ZONE VE: Areas of coastal flooding with velocity (wave

action); base (1% or 100-year) flood

elevations determined.

ZONE X: (Shaded): Areas of the 0.2% flood or 500-

year flood, areas of the base (1% or 100-

year) flood with average depths of less than

1.0 foot or with drainage areas less than one

(1) square mile, and areas protected by

levees from the 1% or 100-year flood.

ZONE X: (Unshaded): Areas determined to be

outside both the 1% (100-year) and 0.2%

(500-year) floodplains.

For purposes of these Regulations, the term “Any V Zone”

includes Zone V and Zones VE and the term “Any A Zone”

includes Zone A, AE, AH, AO and A99, but not the floodway

within these zones.

PART 3 - GENERAL PROVISIONS

SECTION 3.01 - ADMINISTRATION BY THE COUNTY

ENGINEER

The County Engineer or his designee is responsible for the

administration of these Regulations, issuance of permits

required by these Regulations, and enforcement of these

Regulations and maintaining proper records.

SECTION 3.02 - USE OF MAPS

The County Engineer shall use the 1 percent or 100-year

flood elevations and floodway shown on the FIRM referred

to in Section 1.08 of these Regulations to determine which

class of permit may be issued. If the ground elevation of a

specific piece of land is lower than the 1 percent or 100-

year flood elevation, the ground elevation shall serve as the

basis for regulation even if the map indicates that the

property is in a Zone which does not require regulation.

The County Engineer shall forward any discrepancy he

finds in the FIRM to the Administrator via the process

described in Section 3.05.

SECTION 3.03 - MAPS TO BE AVAILABLE

Copies of the Flood Insurance Rate Map (FIRM) will be

maintained in the offices of the County Engineer.

SECTION 3.04 - NOTIFICATION OF ADJACENT

COMMUNITIES AND THE STATE WHEN

ALTERING A WATER COURSE

Prior to any alteration or relocation of a water course, the

County Engineer or the Harris County Flood Control

District, whichever is altering or allowing said alteration

or relocation, shall notify adjacent communities when such

alteration or relocation affects base flood elevations within

the adjacent community. A copy of such notification shall

be submitted to the Texas Commission on Environmental

Quality (TCEQ) and the Federal Emergency Management

Agency (FEMA).

SECTION 3.05 - CHANGES IN MAPS

All requests for letters of map amendment (LOMA), letters

of map revision (LOMR) and conditional letters of map

revision (CLOMR) initiated by any person must first be

reviewed by the County Engineer. The County Engineer

may require the submission of any data he deems relevant

to determining if such approval shall be granted. If the

topographic data was prepared using a digital format it is

requested that a copy of the data be included with the

submittal. The Harris County Flood Control District may

be consulted for its review and approval of any hydrologic

or hydraulic studies accompanying the said request. The

County Engineer may delay the submittal of the requests to

the Federal Emergency Management Agency until after he

is in receipt of the aforementioned approvals from the

Harris County Flood Control District. The Commissioners'

Court may set a fee to cover the cost of reviewing and

processing the said requests.

SECTION 3.06 - USE OF NEW 1 PERCENT OR 100-YEAR

FLOOD ELEVATIONS ON THE BASIS OF

CONDITIONAL LETTER OF MAP REVISION

In the administration of these Regulations the County

Engineer may use new 1 percent or 100-year and 0.2

percent or 500-year flood elevations that are based on

pending channel modifications or other structural projects,

such as retention ponds, that would decrease flood levels

only after the following steps are followed:

(a) The flood study is forwarded to the Federal

Emergency Management Agency (FEMA) and a

conditional letter of Map Revision of the study is

obtained from FEMA.

(b) Documentation is presented to the County

Engineer indicating the channel modifications

will be completed within two (2) years of the

issuance of permits.

transitional aspects of the flood elevations and

prevailing flood insurance rates. The developer

and/or builder in his written statement to the

prospective buyer will recite the flood elevations

prior to and after the completion of said channel

or other structural modifications. A copy of this

statement will accompany the submittal of each

building permit application.

SECTION 3.07 - RESPONSIBILITY OF OTHER OFFICIALS

Under these regulations the County Engineer is responsible

for all administrative decisions, determinations and duties.

The County Engineer may seek and secure the assistance of

other officials of Harris County and of the Harris County

Flood Control District in making his decisions,

determinations and in performing his duties but is not

required to conform to the recommendations of others,

provided however, any decision by the County Engineer

may be appealed by the process in Section 7.01 et seq. of

these Regulations.

PART 4 - PERMITS

SECTION 4.01 - PERMITS REQUIRED

All development within the unincorporated areas of Harris

County without first securing a permit is prohibited.

SECTION 4.02 – OUTSTANDING VIOLATIONS

No new Permit will be issued to a property so long as there

are outstanding or unresolved violations of Section 4.01

under these Regulations on the contiguous property for

which a permit is sought. For purposes of Section 4.02,

resolution of the violation may be achieved by addressing

the violation in the site plan. The application for a Permit

shall be deemed incomplete if it does not address the

outstanding violations as part of the site plan.

SECTION 4.03 – DUTY TO MAINTAIN DRAINAGE

The current owner of a property is responsible for

maintaining drainage at all times according to the

approved Plans.

SECTION 4.04 - APPLICATION FOR PERMIT

The application for a permit will be on a form prescribed

by the County Engineer and must be supported by the

following:

(a) Two copies of a plan detailing the dimensions of

the property to be developed and showing the

position of the development on the property along

with a sufficient description to locate the

property. The site plan shall be to scale or have

sufficient dimensioning to clearly detail the

location of the development. The County Engineer

may require submittal of a survey map and metes

and bounds description of the property to be

developed.

(b) One copy of a drawing generally detailing the

shape and size of the development proposed.

written notification that all requirements of the

Harris County Flood Control District and Harris

County have been met. (The construction of a

single family dwelling and accessory structures

on an existing pre-developed tract of land is

exempted).

(d) In Non-conforming Subdivisions where the

property is geographically in the 0.2 percent or

500-year floodplain and not above the 0.2 percent

or 500-year flood level, two sets of Plans clearly

indicating the finished floor elevation of a

proposed structure will be at or above the 0.2

percent or 500-year flood level.

(e) On developments where a Class “II” permit is to

be issued the following must be submitted:

1. Three (3) sets of Plans detailing the proposed

development. Plans must clearly indicate that

all provisions of these regulations will be

met. On developments other than residential

accessory buildings less than one hundred

fifty (150) square feet or other insignificant

developments, (i.e. – carports, well houses,

gazebos, etc.) Plans must be sealed by a

registered professional engineer or

registered architect certifying that all

provisions of these regulations will be met if

the development is completed in accordance

with the sealed Plans.

2. A topography survey of the property to be

developed. On single-family, residential, one-

lot developments, an elevation certificate

will satisfy this requirement. This

requirement may be waived for fences or

other insignificant types of development.

3. In cases where a determination must be made

as to whether the construction is a

Substantial Improvement or a result of

Substantial Damage, the information in

Section 2.43 and Section 5.01 et seq. is

required.

In determining whether an application is Administratively

Complete, the County Engineer may require the submission

of additional information, Plans, specifications or

documents if he is unable to determine whether a permit

should be issued from the information submitted.

Developments may require permits from other Local,

State and Federal agencies. The applicant is responsible

for compliance with all applicable regulations and permit

requirements.

SECTION 4.05 - DETERMINATION OF PERMIT

ELIGIBILITY

After the application is determined to be Administratively

Complete, the County Engineer shall:

(a) Determine the Zone on the FIRM in which the land

on which the development is to be made is

located, the 1 percent or 100-year flood and 0.2

percent or 500-year flood elevations where the

development is located and whether the

development is located within the floodway.

1. If the County Engineer determines that the

development is within any “X” Zone, above

the base flood elevations, and all other

necessary reviews and approvals have been

issued, he may issue a Class “I” Permit.

2. If a conditional letter of map amendment

(CLOMA) or a conditional letter of map

revision (CLOMR) has been issued which will

place the development in an “X” Zone and all

other necessary reviews and approvals have

been issued, he may issue a Class “I” permit.

Elevation certificates must be submitted to

verify the development is above the required

elevation.

3. If the development is in, or partially in, any

“A” Zone, below the 1 percent or 100-year

flood elevation in any Zone, any floodway, or

any “V” Zone, the County Engineer shall

determine if a Class “II” Permit should be

issued.

(b) Determinations by the County Engineer under the

following provisions may result in a conditionally

approved Class “I” or Class “II” Permit:

(1) Review the proposed construction or

development to assure that all reviews or

approvals required by other County

regulations are obtained unless otherwise

directed by the County Engineer. This

includes all requirements of the most

recently amended Harris County Flood

Control District’s “Policy Criteria and

Procedure Manual”.

(2) Determine compliance with Section 4.02.

(3) The County Engineer may require the

submittal of additional information, Plans,

specifications or documents if he is unable to

determine whether a permit should be issued

from the information submitted.

SECTION 4.06 - CONDITIONS OF A CLASS “I” PERMIT

A Class “I” Permit will be issued when the County Engineer

determines that the development will be made on land that

is located entirely outside the mapped 1% floodplain or

100-year floodplain and above the base flood elevations

and that all other necessary reviews and approvals

required by County regulations have been obtained.

Structures on lots in Conforming Subdivisions mapped

outside of the 1 percent or 100-year floodplain shall be

issued a Class I Permit.

(a) Location above base flood elevation.

1. In the absence of evidence to the contrary,

the County Engineer shall presume that the

property shown in “Unshaded X” Zone on the

FIRM is above the 1 percent or 100-year flood

elevation.

2. In the “Shaded X” Zone it must be determined

that the lowest adjacent grade (LAG) is above

the 1 percent or 100-year flood elevation

before a Class “I” Permit may be issued. The

County Engineer may rely on data in his

possession to make such a determination or

require the submittal of topographical

information by the applicant.

(b) Where a conditional letter of map change has been

obtained or will be obtained from the Federal

Emergency Management Agency for property

which has been elevated by the use of fill above

the elevation of the 1 percent or 100-year flood,

and detailed Plans have been approved by Harris

County a Class I permit will be issued. The

inspections required in Sections 6.02 (b) (1 & 2)

must be made.

all Non-Conforming Subdivisions must show, in

addition to any other requirements, the following

elevations are met:

1. If the structure is a single family residence the

finished floor shall be a minimum of 12 inches

above the highest adjacent natural grade

when measured 10 feet from the edge of the

slab or 12 inches above the crown of the

adjacent street which ever results in the

highest elevation (an exception may be

granted on sloping properties where the

crown requirement is not achievable).

2. If the structure is other than a single family

residence the slab shall have a minimum of 6

inches of exposure to adjacent grade and be

at least 12 inches above the crown of the

adjacent street (an exception may be granted

on sloping properties where the crown

requirements cannot be achieved).

3. In cases where a structure is located

geographically in the 0.2 percent or 500-year

floodplain and the ground is lower than the

0.2 percent or 500-year level but higher than

the 1 percent or 100-year level, the finished

floor elevation of the lowest habitable floor

shall be elevated at or above the 0.2 percent

or 500-year level.

SECTION 4.07 - CONDITIONS OF A CLASS “II” PERMIT

A Class “II” Permit will be issued when the County Engineer

determines that the development will be made on land that

is located in any “A” Zone, below the 1 percent or 100-year

flood elevation in any Zone, in a floodway, or in a “V” Zone

and that all other necessary reviews and approvals

required by County regulations have been obtained. The

following conditions must be met:

(a) Notwithstanding anything below to the contrary,

no development or other encroachment, including

fill, is allowed in a floodway which will result in

any increase in the base flood elevations within

the floodway during discharge of water of a base

flood.

(b) The following conditions must be met for new

construction or Substantial Improvement of a

structure or repair of a structure with Substantial

Damage.

1. The top of the subfloor of the lowest

habitable floor must be elevated to twenty-

four (24) or more inches above the 0.2

percent or 500-year flood elevation or

twelve (12) inches above the level of the

crown of the nearest public street, whichever

is higher, except in a floodway where the

bottom of the lowest supporting member of

the structure shall be elevated thirty-six (36)

or more inches above 0.2 percent or 500-

year flood elevation.

If the land is located in an “AO” Zone, the top

of the slab of the lowest habitable floor

(including basement) shall be elevated to

thirty-six (36) or more inches above the

depth number in feet specified on the FIRM.

There must be a determination by the County

Engineer, after consultation with the Harris

County Flood Control District, that the

development will not adversely affect the

floodplain, if the development is in excess of

a single family residence on a single lot

within the “AO” zone.

If the land is located in an “A” Zone and no

depth number is specified, the top of the slab

of the lowest habitable floor (including

basement) shall be elevated to at least six (6)

feet above highest adjacent grade (natural

ground).

2. All structures will be constructed and

anchored to prevent flotation, collapse, or

lateral movement of the structure resulting

from hydrodynamic and hydrostatic loads,

including the effect of buoyancy.

3. Construction shall use methods and practices

that will minimize flood damage and

construction materials and utility equipment

that are resistant to flood damage. FEMA

Bulletins 1-93, 2-93 and 3-93 or subsequent

revisions will serve as the guideline for this

requirement.

4. Unless dry-floodproofed, enclosed areas

below the base flood elevation must be

equipped with flood openings or vents

capable of equalizing water levels and

hydrostatic loads. Covers for these openings

must not interfere with the equalization of

water levels in the event of a flood and

should minimize potential blockage by

debris. FEMA Bulletin 1-93 or subsequent

revisions shall serve as the guideline for this

requirement. A licensed architect or

registered professional engineer shall

certify the flood openings.

5. Thermal insulation used below the base flood

elevation shall be of a type that does not

absorb water. See FEMA’s “Flood Damage-

Resistant Material Requirements” Technical

bulletin 2 or subsequent updates and

additions.

6. Water heaters, furnaces, air conditioning

systems, electrical distribution panels and

any other mechanical or electrical equipment

must be elevated to at least twenty-four (24)

inches above the 0.2 percent or 500-year

flood elevation. Separate electrical circuits

shall serve any level below the 0.2 percent or

500-year flood elevation and shall be

dropped from above.

7. Basements may be constructed only in

nonresidential structures, and only on land

which is not in a floodway or “V” Zone, and

must, together with attendant utility and

sanitary facilities, be designed so that below

the base flood elevation the structure is

watertight with walls substantially

impermeable to the passage of water and

with structural components having the

capability of resisting hydrostatic and

hydrodynamic loads and effects of buoyancy.

A registered professional engineer shall

certify that the floodproofing methods used

in the construction of the basement are

adequate to withstand the flood depths,

pressures, velocities, impact and uplift forces

and other factors associated with the base

flood. A record of such certification

indicating the specific elevation to which

such structures are floodproofed shall be

maintained with the County Engineer.

8. All air ducts, loose pipes, propane tanks and

storage tanks located at or below the base

flood level shall be firmly anchored to

prevent flotation. Tanks and ducts shall be

vented to at least twenty-four (24) inches

above the 0.2 percent or 500-year flood

elevation.

9. No fill may be used to elevate structures in

the 1 percent or 100-year floodplain.

Structures may be constructed on an open

foundation, such as piers, or on continuous

foundation walls with properly sized and

located openings. All foundations are

required to be designed by a registered

professional engineer. The Plans shall clearly

show compliance with all provisions of these

regulations. Fill may be used in coastal surge

zones where floodplain fill mitigation is not

an issue, however the standard for

foundations remain the same.

10. All structures shall be designed to withstand

a three second gust basic wind speed of 120

miles per hour. This will ensure structural

rigidity, should design flood elevations be

exceeded, or the structure requires elevation

in the future.

proposed for construction with public funds on

publicly owned recreational property may be

exempted from the requirement to elevate the

lowest floor provided floodproofing measures are

incorporated, and after applicable requirements

of this section are met.

(d) Construction of critical facilities shall be, to the

extent possible, located outside the limits of the

0.2% floodplain or 500-year floodplain (Shaded

Zone X) and any “A” Zone. Construction of new

critical facilities shall be permissible within the

base floodplain if no feasible alternative site is

available.

1.Construction of critical facilities on land

located in the 0.2% (500-year) floodplain or

within the 1 percent or 100-year floodplain

shall have the lowest floor elevated to three

feet or more above the 0.2 percent or 500-year

elevation, or twenty-four (24) inches above

the crown of the adjacent road, which ever

results in a higher elevation.

2. Floodproofing and sealing measures must be

taken to ensure that toxic substances will not

be displaced by or released into floodwaters.

3. Access routes elevated to or above the level of

the base flood shall be provided to all critical

facilities to the extent possible.

(e) Any reduction in floodplain storage or

conveyance capacity within the 0.2 percent or

500-year floodplain must be offset with a

hydraulically equivalent (one-to-one) volume of

mitigation sufficient to offset the reduction. The

reduction may result from development or the

placement of fill within the 0.2% floodplain or

500-year floodplain. Such mitigation shall be

within the same watershed and shall be provided

on the same property or within the same

hydrologic sub-watershed or at an alternate site

meeting the approval of the County Engineer. A

full hydrological and hydraulic analysis must be

submitted to support a request for mitigation

outside the boundaries of the property being

developed. This requirement does not apply to

Coastal Areas where floodplain fill mitigation is

not an issue.

In areas of combined coastal and riverine flood

hazard, this requirement only applies for the

portion of fill placed below the riverine flood

hazard elevation as provided in the FIS or an

approved hydraulic model.

(f) A levee or berm may not be used to reclaim a

property from any floodplain. The removal of a

levee or berm shall not be permitted absent a

determination by the County Engineer, after

consultation with the Harris County Flood

Control District, that the action will not

adversely affect the floodplain.

(g) In addition to the requirements of Section 4.07 (i)

the following conditions must be met by a

manufactured home park that seeks a Class “II”

Permit:

1. The lowest floor of the manufactured homes

will be above the 0.2 percent or 500-year

flood elevation;

2. Adequate surface drainage and access for a

hauler must be provided;

3. Lots must be large enough to permit steps.

Piling foundations must be placed in stable

soil no more than ten feet apart, and

reinforcement must be provided for piers

more than six feet above the ground level;

4. Each manufactured home within the park

shall be placed on a permanent foundation

and anchored to resist flotation, collapse or

lateral movement by providing an anchoring

system installed in accordance with the Texas

Department of Housing and Community

Affairs and the Housing and Urban

Development (HUD) standards for

manufactured housing. Any additions to the

manufactured home must be similarly

anchored. (This paragraph applies to

manufactured homes to be placed or

substantially improved in an expansion to an

existing manufactured home park. This

paragraph does not apply to manufactured

homes to be placed or substantially improved

in an existing manufactured home park

except where the repair, reconstruction, or

improvement of the streets, utilities and pads

equals or exceeds fifty (50) percent of the

value of the streets, utilities and pads before

the repair, reconstruction or improvement

has commenced).

5. All utilities and common facilities including

gas, electrical systems, sewage systems and

water supply systems, must be located and

elevated or constructed to avoid or minimize

flood damage.

6. The fact that the manufactured home park is

located below the 0.2 percent or 500-year

flood elevation must be disclosed on a form

furnished by the County Engineer and

completed by the owner of the manufactured

home park and provided to the manufactured

home lot purchaser or lessee. The owner of

the manufactured home park shall forward a

copy of each notice to the County Engineer.

7. The manufactured home park may not be in a

floodway or a “V” Zone.

8. An evacuation plan must be developed for

evacuation of all residents of all new,

substantially improved or substantially

damaged manufactured home parks or

manufactured home subdivisions located

within the area of special flood hazard. This

plan shall be filed with and approved by the

County Engineer and the Emergency

Management Coordinator prior to permit

issuance.

9. Individual Manufactured Home permits will

not be issued for permitted Manufactured

Home Parks built on or before September 16,

1976.

10. Property owners seeking exception to being

defined as a Manufactured Home Park must

provide an affidavit listing immediate family

members. If exception is granted, individual

manufactured home permits will be issued.

Note: Manufactured Home Parks that

received a Permit and were constructed prior

to September 16, 1976 are governed by the

Regulations in effect when their Permit was

issued, except that all Manufactured Homes

placed or that undergo Substantial

Improvements in said park after April 1, 1987

must comply with this section.

Any existing Manufactured Home Park that

did not hold a Permit before September 16,

1976 and undergoes expansions or

Substantial Improvements must comply

with this section.

(h) The following conditions must be met if the

proposed development for which a Class “II”

Permit is sought includes a water or sanitary

sewer system:

1. The proposed system must be designed and

constructed to minimize or eliminate

infiltration of flood water into the system and

to eliminate discharge of untreated waste

from the system into the flood waters.

2. All joints must be watertight.

3. On-site sewage disposal systems, if they meet

the Revised Rules of Harris County for On-

Site Sewerage Facilities, are allowed.

4. Individual water wells or wastewater

disposal systems must be located to avoid

impairment to them or contamination from

them during flooding.

(i) The following conditions must be met if the

proposed development for which a Class “II”

Permit is sought is a subdivision, including a

manufactured home park.

1. The subdivision must be planned to provide

adequate drainage so as to reduce flood

hazards.

2. If water and sanitary sewer systems are

planned, the Plans must be reviewed to

determine if they meet the requirements of

these regulations.

3. The Plans for development of the subdivision

must be adequate to assure that all public

utilities and facilities (including gas,

electrical systems, sewage systems and water

supply systems) are located and elevated or

constructed to avoid or minimize flood

damage.

4. If a subdivision plan includes 50 or more lots

or is on an area larger than 5 acres the

proposal (plat and/or Plans) must include 1

percent or 100-year and 0.2 percent or 500-

year flood elevations for each lot.

(j) The following conditions must be met if the

proposed development for which a Class “II”

Permit is sought is an expansion of a structure, as

the term is defined by these Regulations, located

in any “A” Zone but not within a floodway or

below the base flood level in any Zone:

1. The expansion must be constructed of

materials resistant to water damage below

the base flood elevation and the expansion

must be designed to minimize flood damage

in accordance with the FEMA approved flood-

resistant materials list (Technical Bulletin 2-

93).

2. The expansion shall be inspected to

determine that the Plans and specifications

for the construction have been followed

before the roof and the outer wall coverings

are in place and again when the expansion is

complete. Inspections will be performed in

the same manner as the inspection required

by Section 6.02 of these Regulations.

(k) Notwithstanding any other provision of these

regulations, no permit will be issued if the County

Engineer determines that the development will

increase flood hazards.

(l) The following additional requirements must be

met for development in the floodway:

1. The bottom of the lowest horizontal sill,

beam or member supporting the structure in

the floodway shall be at least thirty-six (36)

inches above the 0.2 percent or 500-year

flood elevation.

2. An engineering report sealed by a Texas

registered professional engineer containing

as a minimum the following information:

a. A soils report which includes the results

of a soil boring(s) to a depth of five (5)

feet below the depth of any proposed

piles and the geotechnical engineer’s

recommendations for the proposed

structure signed and sealed by a Texas

registered professional engineer; and

b. A hydraulic analysis of pre- and

proposed development conditions

showing that no increase in the elevation

of the base flood will occur as a result of

the development. Signed and sealed by a

Texas registered professional engineer.

3. Structures shall be elevated on posts or

pilings so that the entire structure, exclusive

of the posts or pilings, is thirty-six (36)

inches above the 0.2 percent or 500-year

flood elevation. Fill may not be used to

elevate the structure. The Plans and

specifications for said posts or pilings shall

be prepared by a Texas registered

professional engineer qualified in structural

design and he or she shall certify thereon that

the posts or pilings have been designed to

prevent undermining and structural damage

resulting from erosive velocities of the base

flood. Minimum pile depth shall be

established using historical scour depth,

stream velocity and soil conditions. As a

minimum piles shall be embedded ten (10)

feet below the historical scour depth. Pile

design must take into account hydraulic and

debris loading imposed by the base flood. If

no historical data is available a Texas

registered professional engineer shall

perform a scour analysis using the “Texas

Secondary Evaluation and Analysis for Scour”

methodology. After the placement or

installation of the posts or pilings, or during

or prior to the final inspection or approval of

the structure, the permittee shall furnish to

the County Engineer a certificate from the

said engineer that the posts or pilings have

been constructed in the manner set forth in

the Plans and specifications attached to the

application for a permit. All other

requirements must be met, but must not

increase the base flood elevation.

4. The foundation design requirements

presented herein assume that potential scour

around a foundation system could extend to a

depth as great as ten (10) feet below natural

grade. The foundation system must extend to

a depth below the maximum potential scour

that is adequate to prevent excessive vertical

and horizontal movement of the foundation

system due to design axial and lateral loads

imposed during base flood conditions.

These foundation design requirements

present minimum foundation design

requirements. Foundations must meet or

exceed these minimum design requirements,

regardless of the type of scour protection

provided for the foundation.

a. Design Loads: The structural system of

the building shall be designed, connected

and anchored to the foundation system

to prevent flotation, collapse and

permanent lateral movement resulting

from wind loads, impact loads,

hydrodynamic loads and hydrostatic

loads, including the effects of buoyancy

from flooding equal to the base flood

elevation.

b. Foundation Type: The foundation

system shall consist of a driven pile or a

drilled pier foundation system.

1. Driven Piles: Driven piles may

extend above natural grade and act

as the columns supporting the

elevated portion of the building

above the base flood elevation, or

the piles may be terminated near

natural grade and a reinforced

concrete cap shall be cast on top of

the pile.

2. Drilled Piers: Drilled piers shall be

terminated below natural grade,

and a reinforced concrete cap shall

be cast on top of each pier. Columns

for the building may consist of cast-

in-place concrete connected by

dowels to the pier cap.

c. Type and Size of Driven Pile: Driven

piles shall consist of either twelve (12)

inch (minimum) square pre-stressed

concrete piles or fourteen (14) inch

(minimum) diameter steel pipe piles

with a closed end.

1. Closure Plate: The tip of pipe piles

shall be closed prior to driving by

welding a circular steel plate over

the tip of the pile. The closure plate

shall be flush with the outside of the

pile, i.e. the diameter of the closure

plate shall not be greater than the

outside dimensions of the pipe pile.

The minimum thickness of the

closure plate shall be 3/8 inch. The

weld shall be continuous, and the

closure shall be waterproof.

2. Minimum Wall Thickness: The

minimum wall thickness of the pipe

pile shall be 1/4 inch.

d. Type and Size of Drilled Pier: Drilled

piers shall be eighteen (18) inch

diameter (minimum) and straight-sided

(no belled or underreamed base) and

shall be installed using the slurry

displacement technique in accordance

with the ACI Standard Specification for

the Construction of Drilled Piers (ACI

336.1-94).

e. Minimum Pile and Drilled Pier

Embedment: The minimum embedment

below natural grade for driven piles and

drilled piers shall be twenty (20) feet if

the computed allowable axial capacity of

the driven pile or drilled pier (factor of

safety of at least 2.0 with respect to

ultimate axial capacity) is equal to or

greater than the design axial load

transmitted to the pile.

f. Lateral Restraint of Foundations at

Groundline: The individual piles or piers

shall be braced horizontally with

reinforced concrete tie beams

connecting the pier/pile caps each way

(not diagonally). For piles that extend

above natural grade and act as column

supports for the structure, a reinforced

concrete collar shall be cast around each

pile at the groundline, and the collars

shall be connected each way with

reinforced concrete tie beams. The

purpose of the horizontal bracing at the

groundline is to enhance the lateral

restraint of the individual piles or piers

when scour around a pile or pier reduces

the lateral stiffness of the pile or pier.

g. Anchorage of Timber Building Columns

to Concrete Pile/Pier Cap: The timber

column to concrete pile/pier cap

connection should develop the full

moment capacity of the timber column.

The timber column shall be bolted into a

steel sleeve with a welded steel base

plate that is bolted to the concrete

pile/pier cap using anchor bolts cast into

the cap. The steel sleeve shall be

oversized with the inside sleeve

dimension at least 1 1/2 inch greater than

the column dimension. The gap between

the sleeve and column should be filled

with a high strength non-shrink grout.

The bolt(s) connecting the column to the

sleeve should be designed for uplift

forces and shall be 3/4 inch diameter

minimum. The sleeve assembly and

bolts shall be galvanized.

h. Driven Pile Installation Techniques:

Driven piles shall be installed by driving

alone. Jetting with water or air to create

a pilot hole or to loosen the foundation

soils before or during driving to aid

driving will not be permitted. Piles may

be driven with a vibratory hammer, a

drop hammer, or a diesel or compressed

air-operated pile driving hammer. To

aid in stabbing and aligning piles, pilot

holes may be drilled with a dry auger to

a maximum depth of ten (10) feet. The

pilot hole diameter shall not exceed the

pile diameter or width.

i. Drilled Pier Reinforcement and

Concrete: Reinforcement and concrete

for drilled piers shall be in accordance

with ACI Standard Specification for the

Construction of Drilled Piers (ACI 336.1-

94).

1. Minimum Reinforcement: The

minimum steel area shall be one (1)

percent which is equivalent to six

(6) No. 6 reinforcing bars for an

eighteen (18) inch diameter pier.

2. Concrete: The minimum twenty-

eight (28) day compressive strength

of the concrete shall be 3000 psi.

The maximum nominal course

aggregate size shall be 3/4 inch and

the minimum concrete slump shall

be seven (7) inch.

3. Inspection and Testing: The

Texas registered professional

engineer who designed the

foundation shall observe the

installation of each pier or pile

foundation element and shall

furnish the Permit Division of the

Harris County Engineering

Department a certificate that the

piers or piles have been constructed

per the design Plans and

specifications submitted with the

permit application. Testing in

connection with drilled pier

installation shall be in accordance

with ACI 336.1-94.

5. The area below the base flood elevation shall

not be enclosed. A storage area less than 150

square feet may be allowed, provided the

walls perpendicular to the flood flow are

constructed of materials allowing the free

flow of water and that these walls are no

greater than twelve (12) feet wide. All other

provisions of these regulations must be met.

6. Fences or fence-type walls may be allowed in

the floodway provided it can be

demonstrated the flow of the base flood will

not be impaired and that base flood

elevations will not be increased during the

discharge of the base flood.

(m) The following conditions must be met if the

proposed development is for the construction of

a bridge or the repair or replacement of an

existing bridge:

1. Unless otherwise directed by the County

Engineer, the construction of a bridge or the

repair or replacement of an existing bridge

must be in accordance with the criteria for

bridges as found in the Criteria Manual for the

Design of Flood Control and Drainage Facilities

in Harris County, Texas and the Regulations of

Harris County, Texas for the Approval and

Acceptance of Infrastructure.

2. Unless otherwise directed by the County

Engineer, a conditional letter of map revision

(CLOMR) and a letter of map revision (LOMR)

must be submitted for all bridge projects that

modify the base flood elevation or modify the

geometry of the channel or bridge.

(n) The following additional requirements must be

met for development in “V” Zones:

1. The bottom of the lowest horizontal

structural member of the structure

(excluding the pilings or columns) must be

elevated to or above a level thirty-six (36)

inches above the 0.2 percent or 500-year

flood elevation. Fill may not be used to

support the structure, only to elevate the lot.

2. Structures shall be elevated on posts or

pilings and meet all the requirements of

construction in the floodway.

3. Development must be located landward of the

reach of mean high tides.

4. Sand dunes or mangrove stands may not be

altered.

5. The space below base flood elevation must be

either free of obstruction or constructed with

non-supporting breakaway walls, open wood

lattice-work, or insect screening intended to

collapse under wind and water loads without

causing collapse, displacement, or other

structural damage to the elevated portion of

the building or supporting foundation

system. For purposes of this section, a

breakaway wall shall have a design safe

loading resistance of not less than 10 and no

more than 20 pounds per square foot. Use of

breakaway walls which exceed a design safe

loading resistance of 20 pounds per square

foot (either by design or when so required by

local or State codes) may be permitted only if

a qualified registered professional engineer

or architect certifies that the designs

proposed meet the following conditions:

a. Breakaway wall collapse shall result

from a water load less than that which

would occur during the base flood; and,

b. The elevated portion of the building and

supporting foundation system shall not

be subject to collapse, displacement, or

other structural damage due to the

effects of wind and water loads acting

simultaneously on all building

components (structural and

non-structural). Maximum wind and

water loading values to be used in this

determination shall each have a one

percent chance of being equaled or

exceeded in any given year (100-year

mean recurrence interval). Such

enclosed space shall not be used for

habitable purposes. The structure shall

be certified to withstand a three second

gust basic wind speed of one hundred-

thirty (130) miles per hour.

SECTION 4.08 - ISSUANCE OF PERMITS

When the County Engineer determines which, if any,

Permit shall be issued, he shall issue the Permit after

obtaining a signed certification from the permittee or the

permittee's agent, or attorney that the application

complies with all local, state, and federal laws.

SECTION 4.09 - VESTED RIGHTS

Subject to Local Government Code § 245.004(9), the rights

to which a permit applicant is entitled shall accrue are as

follows:

1. Projects with a completed or unexpired

administratively complete application for

Preliminary Plat submitted (does not include General

Plans) to Harris County or a municipality on or before

midnight of the effective date of the most currently

amended Regulations provided that the project is not

Substantially Modified; or

2. An administratively complete development permit

application that is submitted to the County Engineer

on or before midnight of the effective date of the most

currently amended Regulations provided the project

is not Substantially Modified; or

3. An administratively complete submitted drainage

report for a development project to the County

Engineer on or before midnight of the effective date

of the most currently amended Regulations provided

the project is not Substantially Modified.

It is the responsibility of the permit applicant to

demonstrate a project’s entitlement to vested rights under

this Section. If a permit applicant believes they are

entitled to a vested right, that determination is to be

completed prior to the filing of an administratively

complete permit application.

Dormant projects as defined under Texas Local

Government Code Section 245.005 are subject to review

under these Regulations.

If no progress has been made towards completion of a

project, the project will be deemed a Dormant Project and

an expiration date of two years will be placed on the

associated Permit. Progress includes any one of the

following:

1. an application for a final plat or plan is submitted to

a regulatory agency;

2. a good-faith attempt is made to file with a

regulatory agency an application for a permit

necessary to begin or continue towards completion

of the project;

3. costs have been incurred for developing the project

including, without limitation, costs associated with

roadway, utility, and other infrastructure facilities

designed to serve, in whole or in part, the project

(but exclusive of land acquisition) in the aggregate

amount of five percent of the most recent appraised

market value of the real property on which the

project is located;

4. fiscal security is posted with a regulatory agency to

ensure performance of an obligation required by the

regulatory agency; or

5. utility connection fees or impact fees for the project

have been paid to a regulatory agency.

A permit application, plat application, or development

plan application approved under Section 4.09 Vested

Rights does not relieve an applicant from the

requirement to comply with Texas Water Code 11.086.

Harris County’s review under Section 4.09 Vested Rights

is not intended to impair or impact a property owner’s

remedies at law or in equity.

SECTION 4.10 - VESTED RIGHTS DETERMINATION

Any permit applicant who believes that they have

obtained a Vested Right shall submit to the County

Engineer prior to the submission of an Administratively

Complete permit application, a petition explaining the

factual and legal bases upon which the person relies to

support the contention that they have a particular vested

right and consequently, is exempt or not subject to a

particular provision of these Regulations. The petition

shall include, at a minimum, the following:

1. The name, mailing address, phone number, and fax

number of the permit applicant (or the permit

applicant’s duly authorized agent);

2. Identification of the property for which the person

claims a vested right;

3. Identification of the permit applications for which

the applicant seeks relief under this Section;

4. Identification of the “project” as that term is

defined in Tex. Loc. Gov’t Code § 245.001(3) and

the permit application, permit, plat, drainage

project, or drainage report that gives rise to the

project;

5. Identification of the original application for the

first permit in the series of permits required for

the project, as described in Tex. Loc. Gov’t Code §

245.001(1) and § 245.002(a) & (b) and each

subsequent permit application or permit

constituting the series of permits, by type of permit

and dates filed or approved by the County

Engineer;

6. Identification of all pertinent provisions of these

Regulations in effect at the time the original

application for the permit was filed that (a) the

permit applicant contends control the approval,

disapproval of the application for a permit for

which relief is sought, pursuant to Tex. Loc. Gov’t

Code § 245.002(a) & (b);

7. Identification of all the specific provisions of these

Regulations that the permit applicant contends do

not apply to the project due to Vested Rights;

Within 15 days of receipt of a petition, the County

Engineer shall make a determination as to whether the

petition contains the information required above. If the

County Engineer determines that the petition is not

complete, he must notify the permit applicant in writing

within 5 days of the determination and note the

deficiencies. Within 30 days of the receipt of a petition

that meets the minimum requirements above, the County

Engineer shall render a determination that grants the

relief requested in the petition, in whole or in part, or

denies the requested relief, in whole or in part. Prior to

rendering the determination, the County Engineer may

request a pre-determination meeting with the permit

applicant to discuss the person’s Vested Rights claim and

may request additional documents or information related

to the Vested Rights petition.

If the permit applicant believes the County Engineer

determination is made in error, the permit applicant may

file an appeal with the Hearing Examiner under the

provisions of Part 7. The appeal must be filed within 30

days of the County Engineer’s determination.

PART 5 – SUBSTANTIAL DAMAGE

SECTION 5.01 – SUBSTANTIAL DAMAGE

DETERMINATIONS

A County Engineer's representative will use a FEMA-

approved damage estimator and will do an on-site

inspection if necessary to satisfy FEMA guidelines to make

a preliminary determination as to whether the structure

sustained Substantial Damage

For the purpose of determining the value of the structure

before being repaired or reconstructed, the Harris County

Appraisal District’s market value for the structure will be

used. If the applicant wishes to contest this value an

independent certified appraisal may be submitted. Upon

review and concurrence by the Harris County Appraisal

District, this appraised value for the structure will be used

for determining if the improvement is substantial.

In cases where the structure is covered by insurance and

the property owner receives a flood insurance payment, the

“Proof of Loss” statement shall be used by the County

Engineer to value the cost to repair the structure. In cases

where the structure is covered by insurance and the

payment for damage to the structure (excluding contents)

is over 95% of the value of the structure, the structure shall

be deemed substantially damaged regardless of any other

data submitted, except for the submittal of a certified

appraisal showing that the structure is valued higher than

the HCAD taxable value.

For the purpose of rebuilding after a flood event, any single

family residence that received flood damage, but the

finished floor is at or above the 1 percent or 100-year flood

level, cannot be substantially damaged, if they meet the

minimum federal elevation requirement for rebuilding.

This does not apply to enlargements/expansions or any

other work, except flood damage repairs.

SECTION 5.02 – NO REPAIRS TO A SUBSTANTIALLY

DAMAGED STRUCTURE WITHOUT A PERMIT

If a structure is determined to be Substantially Damaged

and any repairs are made, it must be brought into

compliance with the most recently amended Floodplain

Management regulations. The property owner must obtain

a Permit prior to commencement of Substantial

Improvement under Section 2.45.

SECTION 5.03 - REBUTTING THE SUBSTANTIAL

DAMAGE FINDING

In accordance with Section 5.02, a property owner may

contest the County Engineer’s finding of Substantial

Damage by providing an estimate by an independent Texas

licensed property and casualty adjuster showing lower cost

to repair the structure to pre-damage condition or

submitting a certified appraisal showing that the structure

is valued higher than the HCAD taxable value.

PART 6 - PERMITTEE

SECTION 6.01 - RESPONSIBILITIES OF ALL PERMITTEES

All permit holders, regardless of the type of permit held,

must:

(a) Remove all soil deposits resulting from runoff

and/or from vehicular construction traffic and/or

from site operations from the road or drainage

facility on a daily or more frequent basis in

accordance with the Regulations of Harris County,

Texas for Storm Water Quality Management.

(b) Post the permit on the jobsite in a place visible

from the nearest road or street.

pursuant to a Permit. The County Engineer may

make as many scheduled or unscheduled

inspections as he may deem necessary to enforce

these Regulations. If no specific inspection

standards are set by any part of these Regulations,

the inspection shall only be to determine that the

Plans and specifications furnished with the

permit application are met.

(d) All holders of a Class “II” Permit, or persons

holding a Class “I” Permit issued pursuant to a

conditional letter of map amendment or revision

who wish to make a change to the development,

must submit supplemental Plans and/or

specifications to the County Engineer for his

review. If the changes do not comply with these

Regulations the County Engineer shall not

approve the change. If a change complies with

these Regulations and is approved, a copy of the

supplemental Plans and/or specifications shall be

added to the permittee's file, and the permit shall

be amended by the County Engineer.

SECTION 6.02 - INSPECTIONS

(a) Class “I” Permit holders in Non-conforming

subdivisions shall have the following inspection

conducted by a registered public land surveyor, or

registered professional engineer and results of

said inspection submitted to the County Engineer

in one or both of the following forms:

1. An Elevation Certificate clearly indicating

that the requirements of Section 4.06(c) of

these regulations have been met.

2. A Harris County Foundation Certificate Form

CE1226 indicating that the requirements of

Section 4.06(c) of these regulations have

been met

If these elevation documents are not supplied or if the

finished floor elevation fails to meet the required height,

the permittee has two options.

1. Raise the structure and bring into compliance

or;

2. Have a certificate of non-compliance filed in

the Real Property Records notifying future

purchasers that the structure failed to meet

these requirements and is subject additional

flooding risks.

For structures built on lots geographically located in the

0.2 percent or 500-year floodplain and on ground below

the o.2 percent or 500-year floodplain the following shall

be submitted.

1. An Elevation Certificate must be completed,

signed and sealed by a registered surveyor or

registered engineer indicating the required

minimum elevation of the regulations have

been met.

(b) Class “II” Permit holders or persons holding a

Class “I” permit pursuant to a conditional letter of

map amendment or a Class “I” permit issued for a

stormwater detention or retention system shall

have the following inspections conducted by a

registered professional engineer, registered

public land surveyor or registered architect as

applicable and the results of said inspections

submitted to the County Engineer.

1. Prior to framing or wall construction, a

structure with an established minimum

finished floor elevation shall have an

elevation certificate completed, signed and

sealed by a registered surveyor, or registered

engineer, and submitted indicating the

required minimum elevation of these

Regulations has been met.

2. When the structure is complete and ready for

habitation, a final elevation certificate must

be completed, signed and sealed by a

registered surveyor or registered engineer,

indicating that the finished floor of the

structure, pier and beams or posts are placed

or the lowest horizontal supporting member

is installed, and all elevation requirements

are met. All elevations must be referenced to

the datum on the applicable FIRM.

3. When the structure is complete and ready for

habitation, an as-built certification form

supplied by the County Engineer must be

completed, signed and sealed by a registered

engineer or a registered architect indicating

that all the minimum requirements of these

Regulations have been met.

4. When the development is other than

structural in nature, an as-built certification

form supplied by the County Engineer must

be completed, signed and sealed by a

registered engineer or a licensed architect

indicating that the project has been

completed in accordance with Plans approved

by the County Engineer.

posted on site.

(d) The permittee will be responsible for determining

whether inspections have been made prior to

proceeding with work.

(e) Once all applicable certifications have been

submitted to the County Engineer's office, a final

inspection will be conducted. A certificate of

compliance will be issued by the County Engineer

or his representative if all provisions of the

permit have been met. Should the County

Engineer determine that the applicable

certifications have not been provided and the

provisions of Section 6.02 of these regulations

were not followed, then enforcement procedures

as outlined in Section 8.01 shall commence.

(f) Should the County Engineer have to make

additional inspections or conduct survey work

due to non-compliance with these Regulations,

additional fees may be assessed as outlined in

Section 9.04 hereof.

SECTION 6.03 - SUSPENSION OF PERMITS

Permit suspensions are handled in accordance with the

following provisions:

(a) A permit is suspended when the County Engineer

or his inspector advises the permittee or some

responsible person on the job that the permit is

suspended and posts a written suspension notice

over the Permit at the jobsite.

(b) The following actions by the permittee are

grounds for suspension of a permit:

1. Non-compliance with Section 6.02 of these

regulations.

2. Deviating from Plans and specifications filed

with the County Engineer and refusing to

make corrections required by the County

Engineer.

3. Any grounds for revocation of a permit as

outlined in Section 6.04.

permittee must immediately suspend all work on

the job except that work necessary to abate the

suspension. The suspension will be abated when

the corrective work is performed and has passed

inspection. The abatement will be evidenced by

the removal of the suspension notice by the

County Engineer or his inspector, and the notation

on the Permit Notice by the County Engineer or

his inspector that the work has now been

re-inspected and passed. The suspension notice

may not be removed by any person other than the

County Engineer or his inspector and removal by

any other person will be ineffective.

SECTION 6.04 - PERMIT REVOCATION

Grounds for permit revocation are as follows:

(a) Material deviation from the Plans and

specifications on file with the County Engineer, or

a pattern of consistent deviation from such Plans

and specifications which would demonstrate an

intention to avoid conformity with the

requirements of the permit.

(b) Refusal to uncover work for a mandatory

inspection.

(d) Proceeding with work while a building permit is

suspended, other than such work necessary to

abate a suspension.

(e) An act or acts of violence, or threat or threats of

violence against the County Engineer or his

inspector either on or off the job for the purpose

of intimidating the County Engineer or his

inspector, so that he will not perform his

inspection duties.

(f) Falsifying information in the permit application.

(g) Failing to submit all required certifications as

outlined in Section 6.02.

SECTION 6.05 - PERMIT REVOCATION PROCEDURES

Permits shall be revoked in the following manner:

(a) The County Engineer shall send the property

owner and Permittee a notice of revocation

stating the reason for the permit revocation. The

permit will be revoked 30 days Permittee after

both the property owner and Permittee receive

the revocation notice unless either the property

owner or the Permittee send a response to the

County Engineer contesting the revocation.

Within 15 days of receipt of the response

contesting the revocation, the County Engineer

shall comply with Section 6.05(b).

(b) The County Engineer must file a complaint stating

the reason for permit revocation with the Hearing

Examiner.

1. The Examiner will set a hearing as soon as

practicable, but within 15 days of receiving

the complaint.

2. The Examiner will deliver the original

Complaint, Certificate to Commissioners'

Court and Hearing Notice to the Clerk of

Commissioners' Court to be filed, give one

copy to the County Engineer, and designate

an appropriate person as Serving Agent and

give two copies to him or her.

3. The Serving Agent will take the two copies of

the Complaint and Hearing Notice to the site

where he will:

a. Hand one copy of the Complaint and

Hearing Notice to the permittee, or

b. if the permittee is not an individual or

cannot be found on the site, the Serving

Agent will hand one copy of the

Complaint and Hearing Notice to the

person on the site who appears to be in

charge, or

c. if no person can be found on the site, the

Serving Agent will post the Complaint

and Hearing Notice over the Permit

and/or Notice of Suspension posted at

the job.

d. Upon posting of the Complaint and

Hearing Notice the permit shall be

suspended.

4. The Serving Agent will fill in the return on the

remaining copy, noting on it the date, time

and manner in which he perfected service,

and sign the return and return the remaining

copy to the Hearing Examiner.

5. At the time set for hearing, if the return copy

of the Complaint has been returned to the

Hearing Examiner by the serving agent, and

reflects that service has been perfected, the

Examiner may proceed with the hearing.

6. Hearings will be conducted in the

manner provided for by Section 7.02 of these

Regulations before the Hearing Examiner

appointed by Commissioners' Court and the

Examiner may delegate responsibilities of

Hearing Examiner to his Assistant.

PART 7 - APPEALS AND HEARING PROCEDURES

SECTION 7.01 - APPEALS

If a permit applicant is denied a permit, or has his permit

suspended he may appeal the denial or suspension as

provided in this Section. Additionally, variance denials,

and Vested Rights Determinations may be appealed as

provided under this Section.

The term “appellant” is used to refer to the appealing

party. An appellant must seek his remedy under this

procedure before seeking his remedy in court. Application

for a permit is deemed to be a waiver of the right to

challenge these Regulations before exhausting remedies

herein provided.

(a) Appeals are initiated by the making of complaint

with or by requesting an exception to the

Regulations from the Hearing Examiner in

writing.

(b) The Hearing Examiner will set a time for a

hearing, which will be scheduled as soon as

practicable but within 15 days of the receipt of the

written complaint or request, and shall prepare a

Notice of Public Hearing naming the time and date

of the Hearing. Copies shall be distributed as

follows:

1. The original copy and the Certificate to

Commissioners' Court will be filed with the

Clerk of Commissioners' Court and the Clerk

will prepare a file for the Hearing Notice.

2. The Examiner will set up his own working or

hearing file, in which he will keep one copy.

3. The Examiner will give one copy to the

Appellant.

4. The Examiner will deliver one copy to the

County Engineer. The Hearing will be

conducted as provided in Section 7.02, below.

suspension pending the decision of the Hearing

Examiner.

SECTION 7.02 - HEARING BEFORE THE EXAMINER

At Hearings before the Examiner, the Examiner will hear

the testimony of the County Engineer and any witnesses

called by the County Engineer. The Examiner will hear the

testimony of the appellant and any witnesses called by the

appellant. The Examiner will review all documents and

exhibits submitted to him by the parties. The Examiner

will not be bound by formal rules of evidence and will

control the evidence, reserving to himself the power to

exclude testimony or exhibits he does not consider

relevant. The Hearing Examiner will maintain an accurate

record of the evidence adduced at the Hearing.

SECTION 7.03 - FILING OF EXAMINER'S DECISION

The Examiner will prepare a written decision within three

working days of the Hearing. A copy of his decision will be

filed with the Clerk of Commissioners' Court, the members

of the Commissioners' Court, the Regional Director of the

Federal Emergency Management Agency and with the

County Engineer. The original will be sent to the

appellant's address shown on the permit or permit

application. If a variance is granted, the County Engineer

shall prepare the appropriate permit with any special

requirements that may be required by the conditions of the

variance.

SECTION 7.04 - REVIEW BY COMMISSIONERS' COURT

If the County Engineer, or the appellant wishes to appeal

the Examiner's decision, a written objection must be filed

with the Clerk of Commissioners' Court within ten (10)

days of the date the Examiner's decision is filed. The Clerk

will notify the Hearing Examiner who will place the matter

on the Agenda of Commissioners' Court for review at the

next meeting of Commissioners' Court. If the objection is

filed by the County Engineer, notice that the matter is on

the agenda will be sent to the appellant by mail at the

appellant's address shown on the permit or application.

Commissioners' Court will review the matter. The

Commissioners' Court may either affirm or reverse the

decision of the Hearing Examiner. A suspension of a permit

upheld by the Hearing Examiner will not be abated pending

the review of Commissioner's Court.

SECTION 7.05 - VARIANCES

If any person wishes an exception to any provision of these

Regulations, he shall request a variance in the manner

prescribed for the filing of an appeal by 7.01 and 7.02 with

the Hearing Examiner. The Hearing Examiner shall hold a

hearing, and deny or grant the variance. Variances will be

granted only if the conditions of Section 60.6 of the Title

44 of C.F.R. are met. Specifically:

(a) The applicant has shown good and sufficient cause.

(b) It has been determined that failure to grant the

variance would result in an exceptional hardship to

the applicant.

increased flood height, additional threats to public

safety, extraordinary public expense, or create

nuisances, cause fraud or victimization of the public.

(d) Variances shall only be issued upon a determination

that a variance is the minimum necessary considering

the flood hazard to afford relief.

Economic hardship shall not constitute the sole basis for

granting a variance. A hearing before Commissioners'

Court regarding variances shall be requested in the manner

provided in Section 7.04 of these Regulations. If a variance

is granted a permit shall be issued and the permittee shall

conform to all applicable provisions of these Regulations

except the Sections for which a variance is granted.

PART 8 - ENFORCEMENT

SECTION 8.01 - ENFORCEMENT

If any person violates any provisions of these Regulations

the County Engineer may notify the County Attorney and

direct him to take whatever action is necessary to remedy

the violation, including but not limited to filing suit to

enjoin the violation and submitting a request to FEMA for

denial of flood insurance. If a violation continues, Harris

County may file a Certificate of Non-Compliance in the Real

Property Records of Harris County. Once the violation has

been resolved any individual may request a Certificate of

Compliance be filed in the Real Property Records of Harris

County. A fee for this action will be charged in accordance

with Section 9.04 of these Regulations. The violator shall

bear this and all other costs of effecting compliance.

SECTION 7.02 - CONTEMPT OF COMMISSIONERS'

COURT

Commissioners' Court may punish contempt by fine or

imprisonment in accord with the provisions of Section

81.023, Texas Local Government Code, as amended. Any

person securing a permit under these Regulations does so

on the representation to Commissioners' Court that he will

comply with the terms of the permit and with these

requirements and other County regulations. Violations of

such representations to Commissioners' Court constitutes

contempt of Commissioners' Court. Additionally,

Commissioners' Court has the power to enforce its Orders

by civil contempt. If the Commissioners' Court finds the

defendant to be guilty of contempt, it will enter such

Orders consistent with general law as it deems appropriate

to punish the person guilty of contempt, and will enter such

other and further Orders enforceable by civil and criminal

contempt, and consistent with its authority under general

laws, as Commissioners' Court deems necessary to enforce

and protect its jurisdiction over the matter, and to uphold

the integrity of these Regulations. Procedures for

contempt proceedings before Commissioners' Court will be

consistent with procedures in actions before other courts

in this State for enforcement of Court Orders, and for the

protection of the jurisdiction of Courts by the process of

contempt.

PART 9 - FORMS AND RECORDS

SECTION 9.01 - FORMS

Forms to be used in the administration of these Regulations

shall be promulgated by the County Engineer.

SECTION 9.02 - MAINTENANCE OF RECORDS

All applications for, and file copies of, permits must be

maintained by the County Engineer for a retention period

of six (6) years. Plans and specifications on file with the

County Engineer may be destroyed after completion of the

structure.

SECTION 9.03 - ELEVATION AND FLOOD PROOFING

RECORDS

For the duration of the records’ retention period, the

County Engineer shall maintain for public inspection and

furnish upon request any certificates of flood-proofing,

information on the elevation of the level of the lowest

habitable floor of all new or substantially improved

structures, and, for a structure which has been

flood-proofed.

SECTION 9.04 - FEES

Fees for permits and inspections are to be set by

Commissioners' Court. Fees shall be paid by cash, cashier’s

check, money order, or personal check. Checks shall be

made payable to the “Harris County Treasurer.” Should the

check be returned for insufficient funds the permit(s) may

be suspended. If the returned check is not resolved in

ninety (90) days, the permit(s) shall become null and void.

Fees shall be paid at the time permit is delivered to the

permittee unless other arrangements have been made and

approved by the County Auditor. Refer to the fee schedule

for the appropriate fee.

All permit fees are to be doubled for all construction

starting prior to obtaining a permit including minimum and

maximum fees.

Charge per square foot shall also include the floors of

attached and detached garages and all building floors of

multiple story buildings.

Permit fees are not refundable.

Inspection fees are charged for each visit to the jobsite.

PART 10 - SEVERABILITY

The provisions of these Regulations are severable. If any

word, phase, clause, sentence, section, provision, or part of

these Regulations should be invalid or unconstitutional, it

shall not affect the validity of the remaining portions and

it is hereby declared to be the intent of the Commissioner's

Court that these Regulations would have been adopted as

to the remaining portions, regardless of the invalidity of

any part.

REGULATIONS OF HARRIS COUNTY, TEXAS

FOR THE APPROVAL AND ACCEPTANCE

OF INFRASTRUCTURE

ADOPTED: DECEMBER 18, 2018

EFFECTIVE: JANUARY 1, 2019

AMENDED JULY 9, 2019

EFFECTIVE JULY 9, 2019

HARRIS COUNTY

ENGINEERING DEPARTMENT

JOHN R. BLOUNT, P.E.

COUNTY ENGINEER

LOYD SMITH, P.E.

ASSISTANT COUNTY ENGINEER

PREFACE

This Regulation is being revised and approved based on the knowledge that

the effective Flood Insurance Rate Maps (FIRMs) do not accurately define

flood risks because they are based on rainfall information that has since been

updated.

The National Oceanic and Atmospheric Administration’s (NOAA) Atlas 14

precipitation frequency analysis indicates that the updated 100-year

frequency rainfall approximates the current 500-year frequency rainfall.

Therefore, this Regulation has been adjusted to reflect that fact.

Upon issuance of the new FIRMs using updated rainfall data as part of the

MAAPnext project undertaken by the Harris County Flood Control District and

FEMA, and concurrent with their adoption, this Regulation may require

adjustments to more accurately regulate flood risks.

TABLE OF CONTENTS

PAGE

SECTION 1 - PRELIMINARY PROVISIONS .............................. 1

Section 1.01 - Authority ......................................................... 1

Section 1.02 - Area Covered by Regulations ............................ 1

Section 1.03 - Purpose ............................................................ 1

SECTION 2 - USE OF TERMS ................................................. 2

Section 2.01 - Accredited Laboratory ...................................... 2

Section 2.02 - Base Flood ........................................................ 2

Section 2.03 - Base Flood Elevation ........................................ 2

Section 2.04 – Buildable Area .................................................. 2

Section 2.05 - Coastal Areas.................................................... 3

Section 2.06 - Conduit ............................................................ 3

Section 2.07 - County Engineer ............................................... 4

Section 2.08 - Curb and Gutter Sections .................................. 4

Section 2.09 - Design Storm Event .......................................... 4

Section 2.10 - Drainage Area Map ........................................... 4

Section 2.11 - Elevation .......................................................... 4

Section 2.12- Extreme Event .................................................. 5

Section 2.13 - FEMA .............................................................. 5

Section 2.14 - Geotechnical Engineer ...................................... 5

Section 2.14a. - Floodplain Easement ........................................ 5

Section 2.15 - HCFCD ............................................................. 6

Section 2.16 - Hydraulic Grade Line ........................................ 6

Section 2.17 - In-Fill Development .......................................... 6

Section 2.18 - Latent Defects .................................................. 5

Section 2.19 - Lot ................................................................... 6

Section 2.20 - Mean Sea Level ................................................. 6

Section 2.21 - Person…. .......................................................... 6

Section 2.22 - Rainfall Frequency .......................................... 7

Section 2.23 - Redevelopment ................................................. 7

Section 2.24 - Residential Lot ................................................. 7

Section 2.25 - Roadside Ditch Sections .................................... 8

Section 2.26 - Sheet Flow........................................................ 8

Section 2.27 - Subdivision ...................................................... 8

Section 2.28 - Substantial Modification .................................. 8

Section 2.29 - Unincorporated Area ........................................ 9

SECTION 3 - GENERAL PROVISIONS ................................... 10

Section 3.01 - Administration by the County Engineer .......... 10

Section 3.02 - Responsibility of Other Officials .................... 10

SECTION 4 - ADMINISTRATIVE PROCEDURES

FOR THE REVIEW OF PLATS ............................ 11

Section 4.01 - Approval Required ........................................... 11

Section 4.02 - Enforcement .................................................... 11

Section 4.03 - Plat Criteria .................................................... 11

Section 4.04 - Exceptions ....................................................... 12

Section 4.05 - Review Procedures ......................................... 14

Section 4.06 - Recordation Requirements ............................... 15

Section 4.07 - Floodplain Easements on Plats ....................... 19

Section 4.08 - Certificates Required on Plats of Property

Located in the Unincorporated Area of ................

Harris County ................................................. 20

Section 4.09 - Alternative Planning Criteria .......................... 22

SECTION 5 - ADMINISTRATIVE PROCEDURES FOR THE

REVIEW OF CONSTRUCTION PLANS ................ 24

Section 5.01 - Submittal Procedures ..................................... 24

Section 5.02 - Construction Plans - General .......................... 24

Section 5.03 - Plan Layout Requirements .............................. 25

Section 5.04 - Standard Detail Sheets ................................... 26

Section 5.05 - Standard Note Requirements .......................... 26

Section 5.06 - Supplemental Requirements ........................... 27

SECTION 6 - DRAINAGE REQUIREMENTS ........................... 29

Section 6.01 - Drainage Policy .............................................. 29

Section 6.02 - Design Requirements ...................................... 30

Section 6.03 - Storm Water Detention ................................... 46

Section 6.04 - Ownership and Easements .............................. 52

Section 6.05 - Submerged Storm Sewers ............................... 54

Section 6.06 - Low Impact Development

and Green Infrastructure ................................ 57

SECTION 7 - PAVING ......................................................... 58

Section 7.01 - Paving Design Requirements .......................... 58

Section 7.02 - Design Requirements ...................................... 58

Section 7.03 - Materials Requirements ................................. 65

Section 7.04 - Specification Requirements ............................ 67

Section 7.05 - Geometric Requirements ................................ 69

SECTION 8 - STRUCTURES AND BENCHMARKS ................... 76

SECTION 9 - TESTING REQUIREMENTS .............................. 78

Section 9.01 - General .......................................................... 78

Section 9.02 - Bedding and Backfill ....................................... 78

Section 9.03 - Subgrade Testing ............................................ 79

Section 9.04 - Flexible Base .................................................. 80

Section 9.05 - Surface Course ............................................... 80

Section 9.06 - Concrete Pavement ......................................... 80

Section 9.07 - Concrete Cores ............................................... 81

Section 9.08 - Structures ...................................................... 81

SECTION 10 - INSPECTIONS ................................................. 82

Section 10.01 - Construction Inspections ................................ 82

Section 10.02 - Notice of Start ................................................ 82

SECTION 11 - ACCEPTANCE OF IMPROVEMENTS .................. 83

WITHIN SUBDIVISIONS

Section 11.01 - Acceptance Procedures ................................... 83

Section 11.02 - Inspection and Re-Inspection Fees .................. 86

SECTION 12 - TRAFFIC ......................................................... 87

Section 12.01 - Traffic Definitions .......................................... 87

Section 12.02 - Left Turn Lanes .............................................. 87

Section 12.03 - Roadside Signs ............................................... 88

SECTION 13 - LANDSCAPE .................................................... 88

Section 13.01 - Landscape Policy ............................................ 88

Section 13.02 - Use of Terms .................................................. 89

Section 13.03 - Construction Activity ...................................... 89

Section 13.04 - Prohibited Activity ......................................... 89

Section 13.05 - Treescape and Screening Requirements for

Commercial Establishments and

Public Buildings ............................................. 90

Section 13.06 - Tree Planting Requirements for

Single Family Residential Lots ........................ 92

Section 13.07 - Preservation of Existing Trees ........................ 93

SECTION 14 – VARIANCES .................................................... 93

SECTION 15 – VESTED RIGHTS ............................................. 94

SECTION 16 – VESTED RIGHTS DETERMINATION ................. 96

SECTION 17 – VESTED RIGHTS APPEALS .............................. 97

SECTION 18 – VESTED RIGHTS HEARINGS

BEFORE THE EXAMINER ................................ 97

SECTION 19 – FILING OF EXAMINER'S DECISION

ON VESTED RIGHTS APPEALS .......................... 98

SECTION 20 – REVIEW OF VESTED RIGHTS

APPEAL BY COMMISSIONERS COURT .............. 98

SECTION 21 – SEVERABILITY .................................................... 98

APPENDICES

Certificates Required on Plats of Property

Located in the Unincorporated Area of Harris County ......................... A

Notary Formats ........................................................................ B

Graphic Requirements ........................................................................ C

Construction Notes to be On All Projects ............................................ D

Construction Notes Involving

Utilities and Paving Work Located Within a

Public Right-of-Way ....................................................................... E

Construction Notes for Esplanade

Openings and Turn Lanes ................................................................... F

Construction Notes for All Projects Located

in the 1% (100-Year) Floodplain and

.2% (500-Year) Floodplain ................................................................. G

Intensity Duration Curves ................................................................. H

Joint Detail For: Knuckle Configuration ..............................................I

Benchmark Requirements ................................................................... J

Uniform Standards for Public Street Naming ...................................... K

REGULATIONS OF HARRIS COUNTY, TEXAS

FOR THE APPROVAL AND ACCEPTANCE OF INFRASTRUCTURE

SECTION 1 - PRELIMINARY PROVISIONS

SECTION 1.01 - AUTHORITY

These Regulations are adopted by the Commissioners' Court of Harris County,

Texas, acting in its capacity as the governing body of Harris County and the

Harris County Flood Control District. The authority of Harris County to adopt

these Regulations and for the contents hereof is derived from the following

statutes: Chapter 232 of the Texas Local Government Code, Texas Local

Government Code Section 240.901, as amended; Texas Transportation Code

Section 251.001 – 251.05 and Section 254.001 – 254.019, as amended; the

Harris County Road Law, as amended, (Special Laws of the 33

Texas

Legislature, Regular Session, 1913, Chapter 17, as amended), and the Flood

Control and Insurance Act, as amended. These Regulations may be amended

at any time by a majority of Commissioners' Court.

SECTION 1.02 - AREA COVERED BY REGULATIONS

These Regulations apply in all unincorporated areas of Harris County, Texas,

and those areas where Harris County maintains the rights-of-way.

SECTION 1.03 - PURPOSE

The purpose of these Regulations is to ensure that the construction of

infrastructure within the County’s rights-of-way perform their intended

function with limited maintenance and repair.

SECTION 2 - USE OF TERMS

SECTION 2.01 - ACCREDITED LABORATORY

An “Accredited Laboratory” is a laboratory that is accredited by the American

Association for Laboratory Accreditation (A2LA) or American Association of

State Highway and Transportation Officials (AASHTO) in the field of

construction materials testing.

SECTION 2.01.a. – ADMINISTRATIVELY COMPLETE

“Administratively Complete” means a completed permit application that is

submitted to the County Engineer along with all required fees and includes all

the required documents or Plans listed on the Administratively Complete

Checklist provided on Harris County Engineering – Permits website. An

Administratively Complete permit application is ready for technical review.

SECTION 2.02 - BASE FLOOD

A “Base Flood” is the national standard on which the floodplain management

and insurance requirements of the National Flood Insurance Program (NFIP)

are based. Special Flood Hazard Areas (SFHAs) are depicted on Federal

Emergency Management Agency (FEMA) Flood Insurance Rate Maps (FIRMs)

and are areas subject to inundation by the base flood having a one-percent or

greater probability of being equaled or exceeded during any given year (this

is also known as a 1% or 100-year flood event).

SECTION 2.03 - BASE FLOOD ELEVATION

“Base Flood Elevation” (BFE) means the calculated elevation or level above

mean sea level that flood waters may reach during the base flood.

Section 2.04 - BUILDABLE AREA

“Buildable Area” means that portion of a residential lot shown on a final

plat upon which a single-family dwelling unit or a multi-family residential

structure may be lawfully constructed, located or placed, including a site

built home, modular home, manufactured home, duplex, townhouse, or a

multi-unit residential building, in accordance with applicable building

restriction lines, covenants, plat notations, and setbacks, if any.

*Buildable Area Graphic

SECTION 2.05 - COASTAL AREAS

“Coastal Areas” means areas which border on bays or estuaries or other

waterways subject to tidal action which are subject to possible flooding or

increased flood levels because of tidal action, hurricane surge or rising water

due to storms, hurricanes or tsunamis. A “coastal area” is not necessarily in a

“V” Zone. In cases where there is a question as to whether an area is a coastal

area, the Harris County Engineering Department shall refer to the FEMA Flood

Insurance Study.

SECTION 2.06 - CONDUIT

A “Conduit” is any open or closed device for conveying flowing water.

SECTION 2.07 - COUNTY ENGINEER

“County Engineer” means the holder of the statutory position of the County

Engineer for Harris County or the employee designated by the County Engineer

to perform a task required by these Regulations.

SECTION 2.08 - CURB AND GUTTER SECTIONS

A “Curb and Gutter Section” is a full width concrete pavement with curb, either

doweled on six-inch (6”) curbs or doweled four-inch (4”) by twelve-inch (12”)

curb or monolithic curb and gutter sections for asphalt concrete pavement.

SECTION 2.09 - DESIGN STORM EVENT

“Design Storm Event” means the rainfall intensity upon which the drainage

facility will be sized. References to rainfall conditions in these specifications

shall apply to “Technical Paper No. 40, U. S. Weather Bureau”, published by the

U. S. Department of Agriculture, Soil Conservation Service.

SECTION 2.10 - DRAINAGE AREA MAP

“Drainage Area Map” means the area map of a watershed, which is subdivided

to show the area served by each subsystem.

SECTION 2.11 - ELEVATION

“Elevation” means height above mean sea level. The North American Vertical

Datum (NAVD) of 1988 (2001 Adjusted) shall be used. Any future studies

changing the Flood Insurance Rate Map (FIRM), which is referenced to a later

re-leveling of the vertical control system shall be used whenever a revised FIRM

becomes effective.

SECTION 2.12 - EXTREME EVENT

“Extreme Event” means a rainfall event, which exceeds the Design Storm Event

up-to and including the 100-year frequency resulting in surcharge of the

underground storm sewer system and overland sheet flow.

SECTION 2.13 - FEMA

“FEMA” means the Federal Emergency Management Agency.

SECTION 2.14.a. – FLOODPLAIN EASEMENT

“Floodplain Easement” means the area of a residential lot shown on a final

plat that is within the 100-year floodplain as determined by the current Flood

Insurance Rate Map (FIRM). The Floodplain Easement will provide notice that

the residential lot is subject to special development and permitting

requirements by local governments implementing flood hazard area

regulations as part of a flood management program developed in compliance

with the National Flood Insurance Program or Texas Water Code Section

16.315. The Floodplain Easement encumbers that portion of a “residential lot”

that may be used for residential purposes which may be flood prone or in a

flood hazard area based on the current FIRM. Improvements constructed or

placed in a Floodplain Easement, including single-family and multi-family

dwelling units, may be subject to additional floodplain management

regulations.”

SECTION 2.14 - GEOTECHNICAL ENGINEER

A “Geotechnical Engineer” is a licensed engineer within the State of Texas who

works for a company registered in the State of Texas that has been accredited

by the American Association for Laboratory Accreditation (A2LA) in

geotechnical testing.

SECTION 2.15 - HCFCD

“HCFCD” means the Harris County Flood Control District.

SECTION 2.16 - HYDRAULIC GRADE LINE

“Hydraulic Grade Line” means the line representing the pressure head available

at any given point within the drainage system.

SECTION 2.17 - IN-FILL DEVELOPMENT

“In-fill Development” means the development of open tracts of land in areas

where the storm drainage infrastructure is already in place and takes

advantage of the existing infrastructure as a drainage outlet.

SECTION 2.18– LATENT DEFECTS

“Latent Defects” means a defect or condition of construction which does not

comply with the construction documents or designs intent which is generally a

hidden or concealed defect which cannot be discovered by reasonable or

customary inspection, examination or observation at either the time of

construction or substantial completion, but which manifests over time.

SECTION 2.19 – LOT

For the purpose of these regulations the term Lot means any platted lot, parcel,

or reserve.

SECTION 2.20 - MEAN SEA LEVEL

“Mean Sea Level” means the average height of the surface of the sea for all

states of the tide as was established by the United States Coastal and Geodetic

Survey in 1929.

SECTION 2.21 - PERSON

“Person” includes any individual or group of individuals, corporation,

partnership, association, or any other organized group of persons, including

State and Local governments and agencies thereof.

SECTION 2.22 - RAINFALL FREQUENCY

“Rainfall Frequency” means the probability of a rainfall event of defined

characteristics occurring in any given year. Information on rainfall frequency

is published by the National Weather Service. For the purpose of storm

drainage design, the following frequencies are applicable:

1. 2-year frequency – a rainfall intensity having a 50% probability of

occurrence in any given year, or nominally likely to occur once every two

years.

2. 3-year frequency – a rainfall intensity having a 33% probability of

occurrence in any given year, or nominally likely to occur once every

three years.

3. 5-year frequency – a rainfall intensity having a 20% probability of

occurrence in any given year, or nominally likely to occur once every five

years.

4. 10-year frequency – a rainfall intensity having a 10% probability of

occurrence in any given year, or nominally likely to occur once every ten

years.

5. 25-year frequency – a rainfall intensity having a 4% probability of

occurrence in any given year, or nominally likely to occur once every

twenty-five years.

6. 100-year frequency – a rainfall intensity having a 1% probability of

occurrence in any given year, or nominally likely to occur once every one

hundred years.

7. 500-year frequency – a rainfall intensity having a 0.2% probability of

occurrence in any given year, or nominally likely to occur once every five

hundred years.

SECTION 2.23 - REDEVELOPMENT

“Redevelopment” means a change in land use that alters the impervious cover

from one type of development to either the same type or another type and takes

advantage of the existing infrastructure in place as a drainage outlet.

Section 2.24 - RESIDENTIAL LOT

“Residential lot” means a lot, parcel or reserve within a subdivision on which

a single-family dwelling unit or a multi-family residential structure may be

lawfully constructed, located or placed, including a site built home, modular

home, manufactured home, townhouse, duplex or a multi-unit residential

building.

SECTION 2.25 - ROADSIDE DITCH SECTIONS

“Roadside Ditch Sections” are ditch sections adjacent to either full width

reinforced concrete pavement or asphaltic concrete pavement.

SECTION 2.26 - SHEET FLOW

“Sheet Flow” means the overland storm runoff that is not conveyed in a defined

conduit and is typically in excess of the capacity of the conduit or roadside

ditch.

SECTION 2.27 - SUBDIVISION

“Subdivision” means a division of any tract of land into two (2) or more parts

for the purpose of laying out any subdivision or any tract of land or any addition

to the city, or for laying out suburban lots or buildings lots, or any lots, and

streets, alleys or parts of other portions intended for public use or the use of

the purchasers or owners of lots fronting thereon or adjacent thereto. A

subdivision includes re-subdivision (replat), but it does not include the division

of land in parcels or tracts of ten (10) acres or more and not involving any new

streets, alleys or easements of access. This definition is based on current state

statutes and should the statutes be changed its new definition would govern.

SECTION 2.28 –SUBSTANTIAL MODIFICATION

Substantial modification shall mean changes to the approved plans, plat, and/or

drainage report or change of use that will increase impervious cover, or the

volume and/or peak discharge of the stormwater runoff from portions of, or

the whole of the project or any other change that would affect the volume or

peak discharge of stormwater runoff that would cause adverse impacts to off-

site properties.

SECTION 2.29 - UNINCORPORATED AREA

“Unincorporated Area” means the area in Harris County, Texas, which is not

within an incorporated area of a city, town, and village or within the

“jurisdiction of the Port of Houston Authority of Harris County, Texas,” being

that area within 2,500 feet of the thread of the Houston Ship Channel that is

eligible for limited purpose annexation pursuant to Texas Local Government

Code §43.136.

SECTION 3 - GENERAL PROVISIONS

SECTION 3.01 - ADMINISTRATION BY THE COUNTY ENGINEER

The County Engineer is responsible for the administration of these Regulations,

approval of plans required by these Regulations, and enforcement of these

Regulations and maintaining proper records. The County Engineer may

delegate particular authority given to the County Engineer under these

Regulations to another member of the Harris County Engineering Department

and an action by such delegated person under such granted authority shall be

deemed an action of the County Engineer.

SECTION 3.02 - RESPONSIBILITY OF OTHER OFFICIALS

Under these regulations the Harris County Engineering Department is

responsible for all administrative decisions, determinations and duties. The

Harris County Engineering Department may seek and secure the assistance of

other officials of Harris County and of the Harris County Flood Control District

in making its decisions, determinations and in performing duties but is not

required to conform to the recommendations of others.

SECTION 4 - ADMINISTRATIVE PROCEDURES

FOR THE REVIEW OF PLATS

SECTION 4.01 - APPROVAL REQUIRED

All development within the unincorporated areas of Harris County is prohibited

without first securing approved plans or plat, if required, and a development

permit issued under the Regulations of Harris County, Texas, for Floodplain

Management.

SECTION 4.02 - ENFORCEMENT

It shall be unlawful for any person to lay out, subdivide or plat any land into

lots, blocks, tracts or streets within the unincorporated area of Harris County

if the land has not been laid out, subdivided and platted in accordance with

these rules and regulations.

SECTION 4.03 - PLAT CRITERIA

For tracts of land located within the extraterritorial jurisdiction (ETJ) of an

incorporated city or town and subject to the jurisdiction of the Planning

Commission or other governing body of that city or town, general

subdivision and layout requirements as established by the applicable

Commission or other governing body shall apply. In the circumstance where

any rule, regulation, procedure or policy lawfully or officially adopted by the

governing body of any city or town exercising jurisdiction within its

extraterritorial jurisdiction is less restrictive than that contained herein, the

standards adopted by these rules and regulations and applicable State law

shall apply.

For all other tracts not located within a municipality’s extraterritorial

jurisdiction or for which the municipality has issued a written certification

stating that a plat is not required to be filed for that subdivision of land in

accordance with Chapter 212 of the Texas Local Government Code, the

following rules and design requirements shall apply:

1. Lots shall be of sufficient acreage to meet minimum requirements for

on-site sewage service per TCEQ Chapter 285.4 Facility Planning

regulations, unless served by public water and/or sewage.

2. Public road rights-of-way shall be a minimum fifty feet (50’) in width

and in conformance with the Geometric Design Guidelines as adopted

by Harris County Commissioners’ Court.

3. A building setback line of not less than twenty-five feet (25’) from the

road right-of-way shall be imposed on tracts intended for construction

of a single-family structure or structures. However, twenty-foot (20’)

building setback lines will be permitted for single-family residential

lots on cul-de-sacs and knuckles. A ten-foot (10’) building setback line

will be permitted on side lots of single-family residential lots. A

building setback line of no less than ten feet (10’) shall be imposed on

all other tracts. These setbacks may be modified if such modifications

comply with County Planning Criteria.

4. Construction of road and appurtenant drainage facilities shall be in

conformance with specifications as set out in these rules and

regulations.

5. Surveyor shall delineate the limits of the 100-year floodplain on a final

plat and designate a Floodplain Easement on that portion of all

residential lots where the buildable area is within the 100-year

floodplain.

6. Financial Surety: A cash deposit, bond, or letter of credit made in

accordance with the Texas Local Government Code 232.004 or

232.0045 and these regulations.

For all tracts not located within a municipality’s extraterritorial jurisdiction,

thoroughfare alignment and right-of-way (ROW) width planning shall follow

the requirements specified in the Thoroughfare Amendment Study for

Unincorporated and Non-ETJ Areas of Harris County, Texas as adopted by

Harris County Commissioners’ Court and any subsequent revisions thereto.

SECTION 4.04 - EXCEPTIONS

Exceptions to platting requirements are established in Section 232.0015 of

the Texas Local Government Code. A brief description follows:

1. A county may not require the owner of a tract of land located outside

the limits of a municipality who divides the tract into two or more parts

to have a plat of the subdivision prepared if the owner does not lay out

a part of the tract as streets, alleys, squares, parks, or other parts of the

tract to be dedicated to public use or for use of lots fronting on or

adjacent to the streets, alleys, squares, or other parts, and the land is

to be used primarily for agricultural use or farm, ranch, wildlife

management, or timber production.

2. A county may not require the owner of a tract of land located outside

the limits of a municipality who divides the tract of land into four or

fewer parts and does not lay out a part of the tract as streets, alleys,

squares, parks, or other parts of the tract to be dedicated to public use

or for use of lots fronting on or adjacent to the streets, alleys, squares,

or other parts to have a plat of the subdivision prepared if each of the

lots is to be sold, given, or otherwise transferred to an individual who

is related to the owner within the third degree by consanguinity or

affinity per Chapter 573, Government Code. If the tract is transferred

to another who is not related within the third degree by consanguinity

or affinity, then the platting requirements of these regulation shall

apply.

3. A county may not require the owner of a tract of land located outside

the limits of a municipality who divides the tract into two or more parts

to have a plat of the subdivision prepared if all the lots of the

subdivision are more than 10 acres in area and the owner does not lay

out a part of the tract as streets, alleys, squares, parks, or other parts

of the tract to be dedicated to public use or for use of lots fronting on

or adjacent to the streets, alleys, squares, or other parts.

4. A county may not require the owner of a tract of land located outside a

municipality to have a plat of the subdivision prepared if all the lots are

sold to veterans through the Veterans’ Land Board program.

5. A county may not require the owner of a tract land to have a plat

prepared if the owner is the state or any state agency, board, or

commission or owned by the permanent school funds of the state unless

the subdivision lays out a part of the tract as streets, alleys, squares,

parks, or other parts of the tract to be dedicated to public use or for use

of lots fronting on or adjacent to the streets, alleys, squares, or other

parts.

6. A county may not require the owner of a tract of land located outside

the limits of a municipality who divides the tract into two or more parts

to have a plat of the subdivision prepared if the owner of the land is a

political subdivision of the state, the land is situated in the floodplain,

and the lots are sold to adjoining landowners.

7. A county may not require the owner of a tract of land outside the limits

of a municipality who divides the tract into two parts to have a plat of

the subdivision prepared if the owner does not lay out a part as streets,

alleys, squares, parks, or other parts of the tract to be dedicated to

public use or for use of lots fronting on or adjacent to the streets, alleys,

squares, or other parts and one part is to be retained by the owner, and

the other new part is to be transferred to another person who will

further subdivide the tract subject to the plat approval requirements.

8. A county may not require the owner of a tract of land located outside

the limits of a municipality who divides the tract into two or more parts

to have a plat of the subdivision prepared if the owner does not lay out

a part of the tract as streets, alleys, squares, parks, or other parts of the

tract to be dedicated to public use or for use of lots fronting on or

adjacent to the streets, alleys, squares, or other parts and all parts are

transferred to persons who owned an undivided interest in the original

tract and a plat is filed before any further development of any part of

the tract.

SECTION 4.05 - REVIEW PROCEDURES

Municipalities in Harris County exercising their extraterritorial jurisdiction

(“ETJ”) in the unincorporated area of Harris County have developed specific

and unique procedures in processing plats. The procedures outlined below

shall be followed for submitting a plat application and plat to a municipality

and Harris County for review and comment. Procedures for submitting a plat

application and plat for property located in the unincorporated area of Harris

County are also included below. For all plats within a municipality’s ETJ, use

the dedicatory language as promulgated by that municipality. For plats not

located in a municipality’s ETJ, required dedicatory language and all plat

certificate requirements are set forth in Section 4.07 and in Appendix “A”

respectively.

Plats Within A Municipality’s ETJ. For plats of property located in the

unincorporated area of Harris County and the ETJ of a municipality, the

owner of the tract being platted shall submit copies of the plat, along with a

plat application, to the municipality exercising ETJ for review and comments,

at which time the municipality may begin its review of the plat. It shall be

the responsibility of the owner of the tract being platted to ensure that the

Harris County Engineering Department and the Harris County Flood Control

District also receive copies of the plat.

Plats Not Located in a Municipality’s Extraterritorial Jurisdiction. For plats

of property located exclusively in the unincorporated area of Harris County

and not in the extraterritorial jurisdiction of any municipality, the owner of

the tract being platted shall simultaneously submit copies of the plat

application and the plat to the Harris County Engineering Department and the

Harris County Flood Control District, at which time they will begin their

review of the plat.

All Plats. Upon Harris County Engineering Department’s receipt of the

original mylar of the plat fully executed by the owners and, as applicable,

approved by the appropriate Planning Commission or governing body, along

with the required documentation described in “Recordation Requirements” in

Section 4.06 below, Harris County Engineering Department will begin its

review of the plat.

If the plat does not meet all the requirements of Section 4 of these

Regulations, the Harris County Engineering Department will provide its

comments to the owner of the tract being platted in accordance with Section

232.0025 of the Texas Local Government Code. If the plat meets all the

requirements set forth in Section 4 of these Regulations, the Harris County

Engineer will sign it. The plat will then be placed on the next available

Commissioners’ Court agenda for approval.

Once approved by Harris County Commissioners Court (“Court”), the Court

will send the plat to the office of the Harris County Clerk for recordation. The

Harris County Clerk shall calculate the required recording fees and notify the

applicant or applicant’s designee of same. Upon receipt of such fees, the plat

will be filed and recorded in the Official Public Records of Real Property and

Map Records of Harris County, Texas.

SECTION 4.06 - RECORDATION REQUIREMENTS

The following documentation is required to be submitted along with the

original mylar of the plat that is to be reviewed by the Harris County

Engineering Department, submitted to Harris County Commissioners’ Court

for approval, and filed with the Harris County Clerk. Harris County will

accept for recordation only those plats printed on the front side of the mylar

or other reproducible material.

1. A title report, or opinion, title policy or certificate or letter from a title

company authorized to do business in the State of Texas must be

provided indicating ownership of the property, all liens against same,

and any existing easements. The title report shall not have been

executed more than sixty (60) days prior to the time the final plat is

received by the Harris County Engineering Department and may

require updating at the request of Harris County personnel. Owners of

property located within the plat must either sign the plat or execute an

Owner’s Ratification of Plat document, as promulgated by the County

Engineer. Furthermore, liens against the property shall be subordinate

to all dedication of streets, rights-of-ways, easements and terms and

conditions referred to on the plat. Lienholders must either sign the plat

or execute a Lienholder’s Subordination to Dedication document as

promulgated by the Harris County Engineer. See Appendix “B” for

notary formats.

2. An original tax certificate from the tax collector of each political

subdivision in which the property is located showing that all taxes

owed to the County, School District, Utility District, and/or any other

political subdivision have been paid in full. If the plat or replat is filed

after September 1 of a year, the plat or replat must also have attached

to it a tax receipt issued by the collector for each taxing unit with

jurisdiction of the property indicating that the taxes imposed by the

taxing unit for the current year have been paid or, if the taxes for the

current year have not been calculated, a statement from the collector

for the taxing unit indicating that the taxes to be imposed by that taxing

unit for the current year have not been calculated. If the tax certificate

for a taxing unit does not cover the preceding year, the plat or replat

must also have attached to it a tax receipt issued by the collector for

the taxing unit indicating that the taxes imposed by the taxing unit for

the preceding year have been paid in full.

This requirement does not apply to the extent of the applicability of

exceptions in Texas Property Code  12.002(e) in regard to certain real

property acquired by will or inheritance or to certain property acquired

by eminent domain.

3. A completed Utility Service Plan, as promulgated by the County

Engineer, shall be submitted. In no case shall a plat be recorded prior

to assurances being given that all applicable State and County reviews

and/or permit(s) have been obtained.

4. A letter from the County Tax Assessor-Collector certifying that the

name of the subdivision to be presented to Commissioners’ Court is not

in conflict with any other previously recorded subdivision. This

requirement applies to the first section of multi-section subdivisions,

all re-plats, and amending plats and is not applicable to street

dedication plats designated by a street name.

5. Approved plans are to be on file with the Engineering Department at the

time the plat is submitted to Commissioners’ Court. However, if the

tract of land is being platted to create reserves for the purpose of sale

only and there are no immediate plans for construction of

improvements on said reserves, then a note shall be placed on the face

of the plat stating:

“Site drainage plans for the future development of this reserve must

be submitted to the Harris County Flood Control District and the

Harris County Engineering Department.”

6. A letter, statement or other instrument from the owner of any privately

owned easement within the plat boundaries where such easement is to

be crossed by streets (either public or private) or public utility or

drainage easements, stating that the owner of such easement approves

such crossing of the private easement for the purposes intended and

depicted on the plat, if such approval is not granted in the original

document conveying the easement.

7. A plat review fee as established by Commissioners’ Court is required

to be submitted.

8. For plats of lots and/or reserves requiring plan review and not

dedicating any public rights-of-way, a non-refundable administrative

fee is assessed in the amount of $10.00 per lot. Reserves are assessed

a non-refundable administrative fee of $20.00 per 100 feet of plat

boundary adjoining road right-of-way rounded to the next highest

increment of $20.00. Payment of administrative fees should be made

payable to Harris County and are due prior to the plat being promoted

to Commissioners’ Court for action. Payment of administrative fees

must be submitted with the Financial Surety/Administrative Worksheet

validated by the Planning Section.

9. For plats proposing the dedication of a public street(s) and construction

of paving and appurtenant drainage, a Financial Surety is required prior

to plat approval and shall be:

A. Made payable to Harris County, unless cash; and

B. In a total amount based upon the following schedule:

RESIDENTIAL SUBDIVISIONS COMMERCIAL AND STREET

DEDICATION SUBDIVISIONS

$50 per lot with average road

frontage less than 100 feet.

$75 per 100 feet of proposed

pavement. The fee shall be

rounded to the next 100 feet.

$75 per lot with average road

frontage 100 feet or greater.

* NOTE:

The minimum financial surety posted in any case shall be $2,500.00.

Included is the non-refundable administrative fee of $10 per lot for

residential subdivisions or $20 per 100 ft. of pavement in commercial

and street dedication subdivisions.

10. For properties being platted in the unincorporated areas of Harris

County, where there is not Extraterritorial Jurisdiction being exercised

for water and sewer facilities, the following requirements for water and

sewage facilities apply:

A. The drinking water supply shall meet the minimum requirements

established by Chapter 341 of the Health and Safety Code and any

other minimum requirements established by the Texas

Commission on Environmental Quality applicable to drinking

water.

B. Any onsite sewerage disposal systems shall be constructed in

accordance with Chapter 366 of the Health and Safety Code and

the Revised Rules of Harris County for On-Site Sewerage

Facilities.

C. Any sewerage facility other than a properly permitted onsite

sewage facility shall be constructed and operated under a valid

permit issued by the Texas Commission on Environmental

Quality.

11. If a property lies within the 100-year floodplain as shown on the most

recent FIRM adopted by Harris County, the floodplain must be

delineated graphically on the final plat. Surveyor shall designate a

Floodplain Easement on that portion of all residential lots where the

buildable area of those residential lots is within the 100-year

floodplain. Refer to Section 4.08 for floodplain easement dedicatory

language.

12. Additional information may be required by the Engineering Department

to clarify or support any of the aforementioned recordation

requirements.

SECTION 4.07 – FLOODPLAIN EASEMENTS ON PLATS

Where the buildable area of a lot, parcel or reserve is intended for

single family or multi-family residential units and is proposed to be placed

within the mapped 100-year floodplain, the final plat shall show that portion

of the 100-year floodplain as a “Floodplain Easement” on the plat. The

Floodplain Easement shall be illustrated on the final plat map as congruent

with the limits of the 100-year floodplain within the plat boundary from the

most recent FIRM and shall be included as a dedication by the property owner

using the language below.

1) Sample Floodplain Easement

”A Floodplain Easement is hereby established over that portion of the

effective 100-year floodplain area as delineated from FIRM PANEL No.

XXXX dated XXXX within the boundary of this final plat, the limits of

which impact the buildable areas of residential lots, wholly or partially,

and within such area is prone to flooding. (*See attached sketch.)

Construction of any type of residential housing within a Floodplain

Easement is subject to additional flood hazard area regulations. A

Floodplain Easement may be abandoned by Harris County

Commissioners Court if the buildable area of a residential lot is

determined to be outside the 100-year floodplain by submitting County

Engineer’s Form 1226, with the applicable documentation and fee, to

the Office of the County Engineer.

2) Abandonment of Floodplain Easement

A Floodplain Easement may be abandoned by using following

procedure:

a) Complete Harris County Engineer Form 1226 including providing proof

that the buildable area of a specific residential lot(s) has been removed

from the mapped 100-year floodplain by a letter of map revision

(LOMR) or a letter of map amendment (LOMA).

b) Submit the applicable fee, to be the same as a permit for a single family

residence outside the floodplain, currently $75.00.

c) Once received, reviewed and approved by the Office of the County

Engineer, a Court Order will be submitted to Commissioners Court,

abandoning the Floodplain Easement on the residential lot(s).

d) Once approved by Commissioners Court the County Engineer will file

the abandonment in the Real Property Records of Harris County.

SECTION 4.08 - DEDICATORY LANGUAGE AND CERTIFICATES REQUIRED

ON PLATS OF PROPERTY LOCATED IN THE

UNINCORPORATED AREA OF HARRIS COUNTY

1. Dedicatory language on the plats must include the following paragraphs

and can be found in Appendix “A” to these regulations:

A. “FURTHER, Owners do hereby dedicate to the public a strip of

land fifteen (15) feet wide on each side of the center line of any

and all bayous, creeks, gullies, ravines, draws, sloughs, or other

natural drainage courses located in said plat, as easements for

drainage purposes, giving the City of (name of city), Harris

County, or any other governmental agency, the right to enter

upon said easement at any and all times for the purpose of

construction and maintenance of drainage facilities and

structures.”;

B. “FURTHER, Owners do hereby covenant and agree that all of the

property within the boundaries of this plat and adjacent to any

drainage easement, ditch, gully, creek or natural drainage ways

shall hereby be restricted to keep such drainage ways and

easements clear of fences, buildings, planting and other

obstructions to the operations and maintenance of the drainage

facility and that such abutting property shall not be permitted to

drain directly into this easement except by means of an approved

drainage structure.”; and

C. “FURTHER, Owners certify and covenant that they have complied

with or will comply with existing Harris County Road Law,

Section 31-C as amended by Chapter 614, Acts of 1973, 63

Legislature and all other regulations heretofore on file with the

Harris County Engineer and adopted by the Commissioners’ Court

of Harris County.”

2. Additional certification on the plat must indicate the floodplain status

of the buildable areas on “residential lots” on the plat, referring to the

applicable Flood Insurance Rate Map panel and effective date.

A. Buildable Areas Outside the Floodplain:

“I, ___________________, a Registered Professional Licensed

Surveyor in the State of Texas, do hereby certify that the buildable

areas for all residential lots are outside [or, are proposed to be

outside, based on engineering plans and specifications submitted to

the County Engineers Office,] the 100-Year Floodplain as shown on

Federal Insurance Rate Map Panel No. [insert panel number] dated

[insert effective date of map]. This certification is based solely on

plotting boundaries from the FIRM Map, and no technical analysis

was conducted.”

B. Buildable Areas in the Floodplain

“I, ____________________ a Registered Professional Licensed

Surveyor in the State of Texas, do hereby certify that the buildable

areas for all or some of the residential lots are located within the

100-year floodplain as plotted from the Federal Insurance Rate Map

Panel No. [insert panel number] dated [insert effective date of map]

and are subject to flooding. The 100-year floodplain is a flood hazard

area prone to flooding, and subject to additional floodplain

management regulations.”

3. Floodplain easement dedicatory language must be shown on the plat if

a Floodplain Easement is required in accordance with Section 4.07 Floodplain

Easements.

”A Floodplain Easement is hereby established over that portion of

the effective 100-year floodplain area as delineated from FIRM

PANEL No. XXXX dated XXXX within the boundary of this final plat,

the limits of which impact the buildable areas of residential lots,

wholly or partially, and within such area is prone to flooding. (*See

attached sketch.) Construction of any type of residential housing

within a Floodplain Easement is subject to additional flood hazard

area regulations. A Floodplain Easement may be abandoned by

Harris County Commissioners Court if the buildable area of a

residential lot is determined to be outside the 100-year floodplain

by submitting County Engineer’s Form 1226, with the applicable

documentation and fee, to the Office of the County Engineer.

4. Approved Certificate Language may be found in Appendix “A” to these

regulations.

SECTION 4.09 – Alternative Planning Criteria

Harris County Alternate Planning Criteria for Subdivisions and Platting shall be

adhered to when more stringent than municipality whose extraterritorial

jurisdiction includes any part of unincorporated Harris County. Chapter 42-

Section 3 of the City of Houston’s Ordinance codifies this requirement;

however, the County Planning Criteria applies to all city’s ETJ areas.

Projects following the below County Planning Criteria, are deemed to be more

stringent and said criteria supersedes criteria of any City’s ETJ requirement. To

prevent confusion, any plat using the County’s more stringent criteria, will be

reviewed by the County first, and if found to meet the County Criteria, a letter

will be issued by the County Engineer stating that fact for use by the respective

City.

County Planning Criteria

(These pages left intentionally blank)

SECTION 5 - ADMINISTRATIVE PROCEDURES FOR THE

REVIEW OF CONSTRUCTION PLANS

SECTION 5.01 - SUBMITTAL PROCEDURES

1. A preliminary set of plans shall be submitted to the County Engineer for

review along with a County issued Routing Slip. Upon review, the Plans

will be returned to the consultant with any necessary comments. Plans

may be reviewed electronically by submitting through the online

system using the appropriate application.

2. Upon addressing all the comments, a final review will be conducted by

submitting the marked-up preliminary set, a reproducible set, and the

routing slip to the County Engineer. The plans will be approved or

additional comments will be made and the sets returned.

SECTION 5.02 - CONSTRUCTION PLANS - GENERAL

For all construction plans submitted to the Harris County Engineering

Department pursuant to these regulations, the following requirements shall

apply:

1. A Professional Engineer, licensed in the State of Texas, is required to

seal, date and sign each sheet of the plans in accordance with rules set

forth by the Texas State Board for Professional Engineers. The seal must

reproduce on all sheets.

2. A cover sheet shall be required for all projects involving three or more

plan and profile sheets. All plan sheet numbers should be included on

the cover sheet or area map. A vicinity map should always be included

to show the project location.

3. Plans for street and/or public improvements shall be standard twenty-

two inch by thirty-four inch (22” x 34”) overall dimensions for all

design in rights-of-way or easements. Site plans may be submitted on

larger sheets when practical.

4. Plans submitted for Harris County Engineering Department approval

shall be on a reproducible material.

5. A North arrow is required on all sheets and should be generally oriented

either upward or to the right.

6. All projects shall be tied to the datum adjustment that matches the

FIRMs or the most current datum available in coastal areas. Equations

may be used to translate other datum adjustments to the required

adjustment.

7. Graphic standards for construction plans submitted shall be in

accordance with those outlined in Appendix “C” to these regulations.

8. If the property lies below the base flood level, the floodplain must be

delineated graphically on all plan sheets.

SECTION 5.03 - PLAN LAYOUT REQUIREMENTS

Plans submitted to the Harris County Engineering Department pursuant to

these regulations shall have the following items:

1. General construction layouts shall be submitted for all paving and

utility projects involving more than three plan and profile sheets. For

the purpose of fulfilling this requirement, paving and drainage layouts

may be combined and water and sanitary sewer layouts may be

combined.

2. A drainage area map shall be submitted and shall include drainage

computations with drainage area and storm water flow labeled.

3. A lot grading plan shall be submitted for residential lots on which

earthwork is proposed that will change the natural topography.

4. A drawing showing existing natural contours at one-foot (1’) intervals

of the land to be developed.

5. A graphical sheet index shall be included on the general construction

layout or on a separate index sheet showing the plan and profile sheet

location and sheet number.

6. Match lines in appropriate locations and not in the intersections of two

streets or cul-de-sac knuckles shall be provided.

7. If a roadway exists where plans are being prepared to improve the

roadway or construct new pavement or to construct a utility, this

roadway should be labeled as to its existing width, type of surfacing and

base thickness if available without destruction of pavement.

8. All improvements shall be labeled as “Proposed” or “Existing” in both

Plan and Profile Views.

9. Include a fire lane designed in accordance with the current Harris

County Fire Code for approval with all commercial site plans.

10. Include a landscape plan designed in accordance with these regulations

for approval with all commercial site plans.

SECTION 5.04 - STANDARD DETAIL SHEETS

For all construction plans submitted to the Harris County Engineering

Department pursuant to these regulations, the following requirements shall

apply:

1. The Harris County standard paving and detail sheets shall be

incorporated by reference in the project specifications and by

construction notes on the plans.

2. The details of special structures not covered by approved standard

drawings, such as stream and gully crossings, special manholes, etc.,

should be included. The details shall be drawn on the detail sheets with

the horizontal and vertical scales equal.

3. The Harris County Engineering “Express Review Sheet” shall be

submitted with each set of plans and be completed including Harris

County Appraisal District account number.

SECTION 5.05 - STANDARD NOTE REQUIREMENTS

The following standard notes shall be included in the plans, where applicable,

as specified below:

1. All projects shall include the notes in Appendix “D” to these regulations.

2. All projects involving paving or utilities located in a public right-of-way

shall include notes in Appendix “E” to these regulations.

3. All projects involving esplanade openings and turn lanes shall include

the notes in Appendix “F” to these regulations.

4. All projects located within the 10% (10-year) floodplain, the 1% (100-

year) floodplain, or the 0.2% (500-year) floodplain shall include notes

in Appendix “G” to these regulations.

SECTION 5.06 – SUPPLEMENTAL REQUIREMENTS

Unless otherwise directed by the County Engineer, the following additional

requirements shall be included with the initial submittal of preliminary plans

or prior to final plan approval as set forth below:

1. Harris County Flood Control District approval is required prior to final

plan approval.

2. Harris County Toll Road Authority approval is required prior to final

plan approval if project encroaches or impact HCTRA right-of-way.

3. Texas Department of Transportation (TxDOT) approval is required

prior to final plan approval if project encroaches or impacts HCTRA

right-of-way.

4. If required, Traffic Impact Analysis approval is required prior to final

plan approval.

5. If project encroaches into a pipeline easement, approval from the

owner of the easement is required prior to final plan approval.

6. If utility connections are proposed, approval from the utility owner

verifying capacity is required prior to final plan approval.

7. If project encroaches into jurisdictional wetlands, approval from the

U.S. Army Corps of Engineers if required prior to final plan approval.

8. Maintenance Agreements for non-standard items located in Harris

County right-of-way are required prior to final plan approval.

9. Harris County Capital Improvement Projects Division Interpose “No

Objection” letter for projects adjacent or affecting capital projects are

required prior to final plan approval.

SECTION 6 - DRAINAGE REQUIREMENTS

SECTION 6.01 - DRAINAGE POLICY

1. Design Requirements

A. The drainage criteria administered by Harris County and

complemented by the City of Houston and the Harris County Flood

Control District Criteria for newly designed areas provides street

drainage design at a 2-year event frequency, and protects from

structural flooding at the 100-year design frequency. Additionally,

in areas in or adjacent to mapped floodplains, structural protection

is provided for the 500-year design event, using those elevations

derived from the effective Flood Insurance Study (FIS). This is

accomplished with the application of various drainage

enhancements such as storm sewers, roadside ditches, open

channels, detention and overland (sheet) run-off.

B. Recognizing that each site has unique characteristics that may

enhance the opportunity to provide proper drainage, the intent of

these criteria is to specify minimum requirements. These

minimums may be modified with prior consent of the Harris

County Engineering Department provided that the objective for the

minimum drainage standards is maintained.

2. Street Drainage Design - Street ponding of short duration is anticipated

and designed to contribute to the overall drainage capability of the system.

Storm sewers and roadside ditch conduits are designed as a balance of

capacity and economics. These conduits are designed to convey less

intense, more frequent rainfalls while attempting to allow traffic movement

during these events. When rainfall events exceed the capacity of the storm

sewer system, the additional run- off is intended to be stored or conveyed

overland in a manner that reduces the threat of flooding to structures.

3. Flood Control Design – Harris County is a participant in the National

Flood Insurance Program. The flood insurance program attempts to

make flood insurance available at low cost by providing for measures that

reduce the likelihood of structural flooding.

4. Relationship to the Platting Process – The approval of storm drainage

systems, detention facilities, and flood channel improvements is a part of

the review process for planning and platting of new development.

SECTION 6.02 - DESIGN REQUIREMENTS

All designs of major thoroughfare drainage facilities, manholes, inlets, bedding

and backfill shall meet the requirements of Standard Specifications, Standard

Drawings and Harris County Regulations.

The Standard Specifications, Standard Drawings, Harris County Regulations, as

well as the most recently adopted City of Houston design guidelines, will apply

for all non-major thoroughfare projects located within Harris County and the

City of Houston ETJ. The most stringent design details shall apply in the event

of any discrepancy.

Note: With prior approval, products listed in the Harris County Special

Specifications 8013 may be used. Alternative types of pipe proposed for use in

storm sewer applications must receive prior approval of the County Engineer.

1. Method of Determining Runoff

A. Area runoff shall be determined using the Rational Formula which

is defined as:

Q = CiA

Where Q = amount of runoff in cubic feet per second (cfs)

C = watershed imperviousness coefficient. See

Figure 1: Minimum “C” Values for Land Use

Types for suggested typical values.

i = rainfall intensity in inches per hour

Implicit in the determination of “i” is when the entire

watershed under consideration is contributing runoff, a

concept known as the Time-of Concentration (T

) ratio,

which are expressed in minutes.

represents the time in minutes required for the runoff to

flow through the drainage area to the point of consideration.

This is defined as:

10 A

0.1761

+ 15 (in minutes)

A = acres of subarea under consideration in the

watershed area

Note: See Appendix “H” for intensity duration

B. Design Storm Events for typical storm sewer design will consist of

a 2-year storm. Unless otherwise directed by the County Engineer,

design rainfall pattern shall follow the requirements specified in

the most recently amended HCFCD Criteria Manual. Rainfall

intensity for storm sewer design must be determined using Region

3 data (Appendix H) for all regions of unincorporated Harris

County.

Figure 1: Minimum “C” Values for Land Use Types

Land Use Type

Runoff

Coefficient

Residential Districts

Lots more than ¾ acres 0.35

Lots ¼ - ¾ acre 0.45

Lot less than ¼ acre 0.55

Multi-Family Areas

Less than 20 DU/AC 0.65

20 DU/AC or Greater 0.80

Business Districts 0.80

Industrial Districts

Light Areas 0.65

Heavy Areas 0.75

Railroad Yard Areas 0.30

Parks / Open Acres 0.18

C. Application of Runoff Calculation Models

(1). The Rational Method shall be used for designs on all areas

served by storm sewer up to 600 acres in size.

(2). Rainfall runoff modeling shall be applied to areas greater

than 600 acres in size or any areas that are drained by an

open channel provided the model takes into account the

storage and ponding in streets. Models must be acceptable

to FEMA if they are to support a submittal for a map change.

D. Coefficients for the Rational Method.

(1). The runoff coefficient “C” values in the Rational Method

formula will vary based on the land use. Minimum to be used

is shown in Figure 1: Minimum “C” Values for Land Use

Types.

(2). Alternatively, when the area is not outlined in Figure 1, the

runoff coefficient “C” in the Rational Method formula can be

calculated from the equation:

C = 0.6Ia + 0.2

Where C = Watershed coefficient

Ia = percent impervious area (expressed as a

decimal)

(3). If the alternate form is to be submitted, a calculation of the

computation of C is to be provided as part of the drainage

calculations.

2. Design of Storm Sewers

1. Storm sewers shall be designed using the Manning Equation in

combination with the Continuity Equation. Proper consideration

will be given to the units of measure, whether English or metric.

2. The Manning Equation is defined as:

V = (K/n)R

2/3

Where K = 1.49 for English units

n = 0.013 for concrete pipes and

0.024 for CMP pipes

V = velocity in feet per second

R = hydraulic radius of the conduit in feet

which equals area/wetted perimeter

= friction slope as headloss per length

3. The Continuity Equation is defined as:

Q = VA

Where Q = Discharge or runoff in cubic feet per

second (cfs)

V = velocity in feet per second

A = Cross-sectional area of conduit in square

feet

4. Design Frequency

(1). Newly Developed Areas – The design storm event for sizing

storm sewers in newly developing areas shall be a two (2)

year rainfall.

(2). Redevelopment or In-Fill Development with Increased Rate

of Runoff – The existing storm drain serving redevelopment

or infill development shall be evaluated in accordance with

conditions outlined below, using a 2-year rainfall, assuming

existing development conditions. Afterwards the storm drain

shall be re-evaluated with the proposed re-development, or

in-fill development, in place.

(a). If the hydraulic gradient is twelve inches (12”) or less

above the top of curb with the flow in the receiving

channel at the top of the outfall pipe and no structures

are threatened by the project, then no improvements

to the existing storm drain are required.

(b). If the extreme event analysis indicates that structures

are threatened by flooding, the applicant has the

option of either making improvements to the existing

storm drain or providing detention or improving the

receiving stream and not impacting downstream

conditions.

5. Velocity Considerations

(1). Storm sewers should be constructed to convey the design

flow in sub critical hydraulic conditions if possible.

(2). Minimum 2-year flow velocities should not be less than three

feet (3’) per second with the pipe flowing full, under the

design conditions.

(3). Maximum 2-year flow velocities should not exceed eight feet

(8’) per second.

6. Pipe Sizes and Placement

(1). Soil boring with logs shall be made along the alignment of all

storm sewers having a cross section equal to or greater than

seventy-two inches (72”) in diameter or equivalent cross

sectional area. Each boring shall be taken at intervals not to

exceed five hundred (500) linear feet and at a depth of less

than three feet (3’) below the flow line of the sewer. The

required bedding will be determined from the soil boring.

(2). The storm sewer and inlet lead shall be designed with a

minimum of twenty-four inch (24”) inside diameter or

equivalent cross sectional area. Box conduits shall be a

minimum of two feet (2’) by two feet (2’). Closed conduits,

either circular, elliptical, or box, shall be selected based on

hydraulic principles and economy of size and shape.

(3). Larger pipes upstream should not flow into smaller pipes

downstream unless construction constraints prohibit the use

of a larger pipe downstream, or the improvements are

outfalling into an existing system, or the upstream system is

intended for use in detention.

(4). Match crowns of trunk storm sewer pipe at any change in

pipe size unless severe depth constraints prohibit the

matching of crowns. Severe depth constraints include any

system in which the outfall system exists and the designed

storm system cannot achieve 2 feet or more of cover at the

point of lowest cover without additional fill. This includes:

(a). Any system that includes a lake or detention pond, and

the depth of the storm sewers is constrained by that lake

or detention pond, and the designed storm sewer system

cannot achieve 2 feet or more cover at the point of

lowest cover without additional fill.

(b). Any time there is a conflict with the existing utility

system which cannot be reasonably relocated. This

includes large diameter water lines, underground

electrical conduits, underground telecommunication

conduits, petrochemical pipelines, or sanitary sewers.

(c). Any time there is a conflict with a proposed sanitary

sewer system which cannot be avoided due to design

criteria constraints. This includes but may not be

limited to sanitary sewers and their service leads.

(d). The saving of specimen trees which would be harmed

by fill on lots with a minimum lot size of 8400 sf. A tree

survey must be provided showing location, size and

species of trees proposed to be saved.

(5). Locate storm sewers in public street rights-of-way or in

approved easements. Proposed storm sewers shall not be

laid parallel to and under proposed or existing pavement.

Parallel storm sewer must be laid at least tw0 feet (2’) from

the back of curb or edge of pavement to the outside edge of

the pipe. Perpendicular roadway crossings are acceptable.

(6). All precast, reinforced, concrete conduits must be laid in a

straight line. Deflection in accordance with manufacturer’s

specifications will be allowed if on approved plans.

(7). All public side lot or back lot drainage facilities shall be

underground storm sewer systems designed in accordance

with these Harris County standards. Drainage swales are

permitted for off-site sheet flow only. Private, individual lot

drainage is exempt from this requirement except when

discharging into a public right-of-way.

(8). In all easements restricted to storm sewers, the conduit shall

be centered within the limits of the easement. The width of

the easement shall be two (2) times the depth plus the

diameter of the pipe rounded up to the next highest five foot

(5’) increment. The minimum shall never be less than twenty

feet (20’).

(9). For storm sewers located in easements adjacent to public

street rights-of-way, the minimum width shall be increased

for larger pipe or conduit by requiring that a minimum

distance of five feet (5’) shall be maintained between the

easement line and the outside edge of the sewer, and a

minimum distance of two feet (2’) shall be maintained from

the right-of-way line to the outside edge of the sewer pipe or

conduit.

(10). Do not place the bell of the RCP within an inlet, junction box,

or manhole structure. The bell must be cleanly sawed and

removed prior to placement.

7. Starting Water Surface and Hydraulic Gradient

(1). The hydraulic gradient shall be calculated using the top of

the outfall pipe as the starting water surface elevation.

(2). Should the upstream pipe be higher than the hydraulic grade

line at drop in pipes invert, then the hydraulic grade line shall

be recalculated assuming the starting water surface to be at

the top of the pipe at that point.

(3). For the design storm (a two year frequency), the hydraulic

gradient shall at all times be below the gutter line.

8. Manholes

(1). Use manholes for precast conduits at the following locations:

(a). Size or cross section changes.

(b). Inlet lead and conduit intersections.

(c). Changes in pipe grade.

(d). At a maximum space of seven hundred feet (700’)

along a conduit run.

(2). Use manholes for monolithic concrete storm sewers at the

same locations as precast conduits, except they are not

required at the intersection of inlet leads unless needed to

provide maintenance access.

(3). All manholes constructed on proposed or existing major

thoroughfares shall be constructed in accordance with Harris

County Specifications.

(4). All precast manholes must conform to ASTM C 913.

Cored or blocked out pipe openings must be designed to

closely fit the outside diameter of the proposed tie in. Precast

manholes with thin-wall knockouts to accommodate a range

of pipe sizes will not be allowed in the right-of-way.

(5) Incoming and outgoing reinforced concrete pipe must be at

least three inches (3”) away from the corner of the junction

box structure as measured from the outside edge of the pipe

to the inside corner of the structure. If the junction box

structure is pre-cast to accept the corner tie in or the

structure was otherwise designed to accept this, the design

engineer shall submit the design plans and specifications to

Harris County prior to street acceptance.

9. Inlets

(1). Locate inlets at all low points in gutter or at intermediate

points in the profile grade to provide proper drainage.

(2). Inlets should not be placed within driveway locations/limits

but should be placed in the center of the lot.

(3). Valley gutters across intersections are not permitted.

(4). Inlet spacing is a function of gutter slope and should be

designed to conform with the Pavement Design

Requirements and Drainage Design Requirements of these

design guidelines.

(a). Local and collector street section: For minimum gutter

slopes, the maximum inlet spacing shall be a gutter run

of seven hundred feet (700’) at high point in pavement

or the adjacent inlet, with a maximum of one thousand

four hundred feet (1400’) of pavement draining

towards any one inlet location.

(b). On cul-de-sac or partial cul-de-sac sections, gutter runs

shall be limited to four hundred feet (400’).

(c). On major thoroughfares, gutter runs shall be limited to

three hundred feet (300’).

(5). Use only Harris County and City of Houston Standard Inlets

shown in Figure 3, “City of Houston Standard Inlets

Acceptable to Harris County.”

(6). Storm sewer leads must be tied directly into the face or back

of “B-B” or “H-2” inlet box and shall not be tied into the short

side of “B-B” or “H-2” inlets.

(7). Do not use “Beehive” grate inlets or other “specialty” inlets.

(8). Do not use unprotected grate-top inlets in unlined roadside

ditch.

(9). Do not place inlets in circular portion of cul-de-sac streets

unless special conditions warrant otherwise and are included

on approved plans and are approved prior to placement.

(10). If drainage will enter or leave proposed pavement then inlets

must be located at the end of proposed pavement.

(11). Do not locate inlets adjacent to median openings.

(12). Place inlets on side streets intersecting major streets, unless

special conditions warrant otherwise and are included on

approved plans.

(13). All precast inlet boxes must conform to ASTM C 913. Cored or

blocked out pipe openings must be designed to closely fit the

outside diameter of the proposed tie in. Precast inlets or

catch basins with thin-wall knockouts to accommodate a

range of pipe sizes will not be allowed in the right-of-way.

(14) Incoming and outgoing reinforced concrete pipe must be at

least three inches (3”) away from the corner of the inlet

structure as measured from the outside edge of the pipe to

the inside corner of the structure. If the inlet structure is

pre-cast to accept the corner tie in or the structure was

otherwise designed to accept this, the design engineer shall

submit the design plans and specifications to Harris County

prior to street acceptance.

(15). Type “E” inlets shall not be used in the right-of-way, with

exception for temporary locations for interim drainage in

areas of future half boulevard. Use of Type “E” inlets in this

application shall be confirmed by the County Engineer.

FIGURE 2: City of Houston Standard Inlets Acceptable to Harris County

Inlet

Type

Application Capacity City of Houston

Drawing Number

A Parking Lots / Small Areas

2.5 cfs 02632-01

B-B Residential / Commercial

5.0 cfs 02632-04

C Residential / Commercial

5.0 cfs 02632-06

C-1 Commercial

10.0 cfs 02632-06

C-2 Commercial

15.0 cfs 02632-06

C-2A Commercial

20.0 cfs 02632-06

D Parking Lots

2.0 cfs 02632-07

D-1 Small Areas

2.5 cfs 02632-08

E Temporary Drainage Swales 20.0 cfs 02632-09

& 02632-10

H-2 Residential / Commercial

5.0 cfs 02633-01

& 02633-02

Consideration of Overland Flow

A. Extreme Event Analysis – The design frequency for consideration

of overland sheet flow will consider extreme storm events. These

events, which exceed the capacity of the underground storm sewer

system and result in ponding and overland sheet flow, shall be

routed to drain along street rights-of-way or open areas and

through the development to a primary outlet.

B. Relationship of Structures to Street

(1). All structures shall be higher than the ponding anticipated in

areas immediately adjacent to the structure as anticipated by

the extreme event analysis.

(2). The engineer shall show the proposed structure’s minimum

slab elevation at eighteen inches (18”) above the 1% 100-

year floodplain, one-foot (1’) above the ponding depth within

a ten foot (10’) radius of the proposed buildable area, or at

or above the 500-year floodplain elevation as determined by

the Floodplain Insurance Study, whichever is applicable and

greater.

(3). Slab and drainage elevations, conduit locations, and grading

for the extreme event shall be shown on a specifically

designated page of construction plans.

(4). An engineer’s certification stating that the grading,

elevations, and drainage are within engineering tolerances

of the approved subdivision plan set without publicly

dedicated streets shall be submitted prior to issuance of

single family residential structure permits associated with

that approved plan set.

C. Calculation of Flow

(1). Streets will be designed so that consecutive high points in the

street will provide for a gravity flow of drainage to the

ultimate outlet.

(2). The maximum depth of ponding at high points will be six

inches (6”) above top of curb during an extreme event

condition.

(3). The maximum depth of ponding at low points will be

eighteen inches (18”) above the top of curb during an

extreme event condition.

(4). Along major thoroughfares and principal arterial streets, the

depth of water along the median gutter section shall not

exceed three inches (3”) in depth under the extreme event

condition.

(5). Sheet flow between lots may be provided only in connection

with a defined drainage easement.

(6). A map shall be provided which delineates extreme event flow

direction for both offsite, and through a proposed

development. The map shall also show the method of

discharge to the primary drainage outlet. Positive drainage

must be provided to intercept offsite sheet flow.

(7). In areas where ponding occurs and where no sheet flow path

exists, a calculation must be provided which demonstrates

how the runoff from a 100-year event will be conveyed and

remain in compliance with the other terms of this Section.

D. Interim off-site sheet flow: Drainage swales may be used for

interim offsite sheet flow in lieu of closed conduits in phased

projects and for projects adjacent to existing development. This is

required any time the proposed development will cause ponding on

an adjacent owner’s property.

In areas where the project design incorporates fill adjacent to

the adjacent property, the Contractor shall implement grading

and/or perimeter runoff catchment devices (e.g.- perimeter

ditches) during construction to ensure that adjacent parcels

bordering the project site do not experience increased interim

drainage flows or carry sediment generated as part of

construction activities. The interim drainage allowed to leave

the property shall not exceed the pre-developed conditions.

Where applicable, these practices are in addition to the standard

Storm Water Pollution Prevention design and shall include

additional ditches redirecting site drainage or temporary piping.

This note is not intended to replace or address any liability or

responsibility under Texas Water Code 11.086.

4. Design of Open Channels

A. Design Frequency

(1). Unless otherwise directed by the County Engineer, open

channel design and construction standards shall follow the

requirements specified in the most recently amended HCFCD

Criteria Manual.

(2). Unless otherwise directed by the County Engineer, design

standards for outfalls into channels shall conform to those

standards delineated in the most recently amended HCFCD

Criteria Manual.

B. Determination of Water Surface Elevation

(1). Water surface elevations shall be calculated using Manning’s

Equation and the Continuity Equation.

(2). For the design storm event, the water surface must be

calculated to remain within banks.

C. Design of Culverts

(1). Head losses in culverts shall conform to Texas Department of

Transportation Hydraulic Manual, Chapter 4 – Culverts.

(2). Corrugated metal pipe will not be approved for permanent

culverts in Harris County rights-of-way except at railroad

crossings, and if used underneath the railroad crossing, the

culvert shall be designed to railroad loadings.

D. Design of Outfalls

(1). Unless otherwise directed by the County Engineer, all outfall

designs shall conform to the HCFCD Criteria Manual.

5. Design of Roadside Ditches

A. Design Frequency

(1). Roadside ditch design is permissible only for commercial

areas equal to or less than one (1) acre or for single-family

residential lots. Detention is required in accordance with

Section 6.03 for all other conditions.

(2). The design storm event for the roadside ditches shall be a

two (2) year rainfall.

(3). Design capacity under the two (2) year storm event for a

roadside ditch shall be no less than 0.5 feet below the edge

of pavement or the natural ground at the right-of-way line,

whichever is lower.

(4). The design shall include an extreme event analysis to

indicate that the proposed structures will not be flooded.

(5). Outfall drainage to existing roadside ditches shall be limited

to tracts with frontage along the roadside ditch. If no

frontage to the roadside ditch exists, but it can be shown

with detail topographic surveys that the tract ultimately

drains to the roadside ditch, then outfall will only be

considered with full retention of the storm water during the

design rainfall event.

B. Velocity Considerations

(1). For grass-lined sections, the maximum design velocity shall

be four feet (4’) per second during the design event.

(2). A grass-lined or unimproved roadside ditch shall have side

slopes no steeper than three (3) horizontal to one (1) vertical

(3:1) or as soil conditions will permit. Steeper slopes will be

allowed when the existing right-of-way is limited or other

construction features dictate the design. The steepest slope

shall not exceed two (2) horizontal to one (1) vertical (2:1).

(3). The minimum grade for roadside ditches shall be 0.1 foot per

100 feet.

(4). Calculation of velocity shall use a Manning’s roughness

coefficient of 0.04 for earthen sections and 0.025 for ditches

for paved inverts.

(5). Erosion control methods shall be used when design velocities

are expected to be greater than four feet (4’) per second or

where erodible soil conditions are indicated in the

geotechnical report.

C. Culverts

(1). Culvert length shall be determined by measuring the width of

the crossing and adding a one-foot (1’) shoulder to each edge

of radius of the crossing and the intersection length from the

edge of the shoulder to the flow line of the ditch. The slope

will not be steeper than a three (3) horizontal to one (1)

vertical (3:1) at each end.

(2). Culverts shall be placed at all driveway and roadway

crossings and other locations where deemed necessary. The

size and grade of the culvert(s) shall be provided for each lot.

(3). Pipe culverts shall conform to ASTM C-76, Class III, for

reinforced concrete pipe.

(4). The size of roadside culverts is to be based upon drainage

area. Notwithstanding this requirement, the minimum

culvert size shall be eighteen inches (18”) for residential and

commercial driveways.

(5). All proposed and reasonably expected future culverts shall be

included in the hydraulic profile. The culvert used shall not

create a headloss of more than 0.20 feet greater than the

normal water surface profile without the culvert.

(6). Storm water discharging from a ditch into a storm sewer

system must be intercepted by use of an appropriate

structure (i.e., stubs with ring grates or type “E” manholes).

D. Invert Protection

(1). Ditch invert protection shall be used when velocities exceed

four feet (4’) per second.

(2). Ditch invert protection will be used at the upstream and

downstream ends of all culverts.

E. Depth and Size Limitations for Roadside Ditches

(1). The maximum depth for a roadside ditch shall not exceed

four feet (4’) below the adjacent road centerline top of

pavement. There may be instances where extreme

conditions may warrant a deeper ditch. In those cases,

specific written prior approval must be obtained from the

Harris County Engineering Department.

(2). Roadside ditch bottoms shall be at least two feet (2’) wide,

unless design analysis supports a narrower width and prior

written approval is obtained from the Harris County

Engineering Department.

(3). A minimum distance of two feet (2’) shall be established and

maintained between the right-of-way line and the adjacent

edge of the bank of a ditch.

SECTION 6.03 - STORM WATER DETENTION

1. Application of Detention

A. If new development or redevelopment has the opportunity to drain

directly into a channel maintained by HCFCD, then HCFCD criteria

shall prevail unless otherwise directed by the County Engineer.

(1). If the drainage system for a development project outfalls

directly into a channel maintained by the HCFCD, and the

requirements of the HCFCD include payment of an impact

fee, then no further impact fees or detention will be required

by Harris County Engineering Department.

(2). If redevelopment occurs without increasing the overall

impervious character of the site, or without increasing the

drainage outfall capacity from the site, then no detention will

be required.

(3). If the development involves only one single family residence

where no major changes in existing drainage are proposed

and the tract is not part of a larger development project, then

no detention will be required.

(4). If development involves only lots fronting on County roads,

no detention is required if the developed area is contained

within the 150 foot lot depth fronting the road or the total

impervious area does not exceed the area calculated by

multiplying the 150 foot lot depth by the lot width adjacent

to the County road. This provision is only applicable for

single-family residential lots where no changes in existing

drainage patterns are proposed for the remainder of the lot.

B. Use of on-site detention to mitigate impacts on Harris County

maintained drainage systems is required under these regulations

when either:

(1) It is proposed that commercial development outfall into a

Harris County roadside ditch; or

(2) It is proposed that the tract or development outfall to a

Harris County storm sewer system and the capacity allocated

to the tract in the original design calculations is less than

projected for the proposed development. This shall be

evaluated using either the methodology documented in the

original design calculations or that outlined in these

regulations.

C. Separate from the requirements of 6.03.1.B. above, use of on-site

detention to mitigate impacts on defined channels at or downstream

of the site may be required under Harris County’s Floodplain

Regulations. Unless otherwise directed by the County Engineer,

Harris County will rely on the technical review in accordance with

the most recently amended HCFCD Policy Criteria and Procedures

Manual in determining detention requirements under the most

recently amended Harris County Floodplain Regulations.

D. Where on-site detention is required under both criteria (B and C), the

largest detention storage rate determined under each criteria shall

apply.

2. Calculations of Detention Volume

A. Unless otherwise directed by the County Engineer, design rainfall

shall follow the requirement specified in the most recently

amended HCFCD Criteria Manual.

B. Detention volume for new development areas is to be calculated

based on the gross area of the tract being developed. However, the

County Engineer may grant phased detention for phased

commercial projects based on the portion of the tract being

developed at the time. All future development will require

approval from the County Engineer.

C. Detention volume for redevelopment areas is to be calculated on

the basis of the amount of area of increased impervious cover.

D. Detention volume for areas proposed for gravity outfall shall be:

(1). Roadside ditch outfall – Unless otherwise directed by the

County Engineer, minimum storage rate of 1.0 acre feet per

acre unless a Method 2 hydrologic and hydraulic analysis, as

defined by the most recently amended Harris County Flood

Control District Design Criteria Manual, shows a lower rate

and volume is acceptable. The discharge rate shall be limited

to the capacity of as outlined in Section 6.03 (4)(A).

NOTE: If a method 2 analysis is performed, the minimum

detention volume shall not be less than 0.75 acre-feet per

acre.

(2). Storm sewer outfall – Unless otherwise directed by the

County Engineer, minimum storage rate of 0.75 acre-feet per

acre unless a formal Method 2 hydrologic and hydraulic

analysis, as defined by the most recently amended Harris

County Flood Control District Design Criteria Manual, shows

a lower rate and volume is acceptable. The discharge rate

shall be limited to the existing storm sewer capacity

allocated to the tract.

E. For the areas proposed for pumped/gravity combination outfall, the

following criteria shall apply:

(1). The detention volume shall be the same as D(1) and D(2),

EXCEPT THAT the volume of pumped flow shall be limited

to 50% of total basin capacity.

NOTE: The minimum detention volume shall not be less than

1.0 acre-feet per acre for a pumped/gravity combination

system that outfalls into a roadside ditch and 0.75 acre-feet

per acre for a pumped/gravity combination system that

outfalls into a storm sewer.

(2). Automatic controls shall be incorporated to shut off all

pumping when outfall system capacity is reached.

Additionally, a gravity return line to the detention facility

must be provided for additional head control in the event of

failure of automatic level controls. Pumping cannot be

resumed until the outfall has receded to one-half (½) the

depth of the roadside ditch.

(3). Drain Time – Maximum drain time is four (4) days. If drain

time is longer than four days, use the increase in detention

volume that approximates the drain time as shown in Figure

3. If the maximum discharge rate from the detention facility

to a roadside ditch is insufficient to allow the facility to drain

within seven days, this is likely an indication that the

proposed area to be developed is too large to be

accommodated within the existing roadside ditch. In this

case, an alternative drainage solution may be required which

could include acquisition of off-site drainage easements and

construction of open channel ditches to serve the

development. If the calculated drain time exceeds seven

days, consult with the County Engineer.

FIGURE 3: Increase in Detention Volume

Duration

Increase in Detention

Volume

4 Days 0%

5 Days 5%

6 Days 15%

7 Days 25%

F. When parking areas are used for detention, the maximum depth of

ponding in parking areas shall be nine inches (9”) directly over the

inlet grate.

G. Outfall drainage to existing roadside ditches shall be limited to

those tracts with frontage along the roadside ditch. In cases where

no frontage on roadside ditch exists, but where it can be shown

with detail topographic surveys that the tract ultimately drains to

the roadside ditch, the minimum detention volume shall not be less

than 1.0 acre-feet per acre. The allowable discharge rate to a

roadside ditch shall be limited to the pro-rata share of the existing

capacity of the roadside ditch at the point of outfall or any location

downstream, whichever is less as outlined in Section 6.03 (4)(A).

3. Design of Basin

The following requirements shall apply for basins designed under these

Regulations:

A. The side slope ratio shall be 3:1 or flatter depending on local soil

conditions.

B. The design must either prevent sheet flow down the basin side

slopes or provide for adequate erosion control through the back

slope drains, concrete slopes, or other acceptable methods.

C. Dry bottom basins shall be sloped to drain and dry out between

storm events in order to accommodate maintenance. The minimum

bottom traverse slope shall be three-fourths of one percent

(0.75%), and the minimum pilot channel slope shall be one-tenth

of one percent (0.1%).

D. Wet bottom basins shall meet the following criteria:

(1). A minimum of six feet (6’) of permanent water depth is

required unless the wet bottom is for purposes of wetlands.

(2). A six-foot (6’) width minimum shelf, one-foot (1’) above

static water’s surface elevation is required.

(3). Side slopes must meet the following criteria:

(a). A ratio of 3:1 from shelf to bottom of basin; or

(b). A ratio of 3:1 or flatter depending on local soil

conditions from above shelf to natural ground.

(4). Alternatives to items D(2) and D(3) above may be approved

provided the facility design demonstrates that it can be easily

maintained with due consideration of public safety.

Detention Outfall Facilities

A. The maximum discharge rate for detention facilities shall be

limited to the capacity allowed to the subject tract of the receiving

storm sewer. In the case of a roadside ditch outfall, the rate of

runoff from the front one hundred-fifty feet (150’) of the tract

calculated is defined in Section 6.02 (1) of these regulations,

assuming a runoff coefficient “C” of 0.2. Alternatively, the

allowable discharge rate to a roadside ditch can be calculated based

upon the pro-rata share of the existing capacity of the roadside

ditch at the point of outfall or any location downstream, whichever

is less. Capacity of the roadside ditch shall be computed using

detailed topographic survey of the ditch and Manning’s Equation as

outlined in Section 6.02 (2) (B). Pro-rata share of capacity shall be

computed as the ratio of the detention pond service area (including

the detention pond) that naturally drains to the roadside ditch

divided by the total drainage area of the roadside ditch upstream

of the outfall location.

B. The outfall orifice shall be designed using the following equation:

_________________

Q = CA  2gh

D = Q

/ 2.25 h

Where Q = outflow discharge in cubic feet per

second (cfs)

C = 0.8

A = orifice area

h = head – water surface differential –

typically two feet (2’), but no less than 0.5 feet

g = gravity – 32.2 feet / sec

D = diameter of orifice (inches)

C. Restrictor Criteria

(1). An appropriate sized restrictor system must be installed to

ensure detention volume is utilized. If circular pipe of less

than six inches (6”) is to be used, appropriate measures must

be incorporated to ensure clogging of the outfall pipe does

not occur.

(2). The outfall pipe containing the restrictor shall be a minimum

of eighteen inches (18”) or six inches (6”) greater than the

restrictor pipe size, whichever is larger.

(3). The restrictor shall be located in the upstream end of the

outfall pipe.

D. Outfall Method

(1). The outfall pipe shall be ASTM C76, Class III Reinforced

Concrete.

(2). The restrictor shall be PVC or other material acceptable to

the Harris County Engineering Department.

(3). All gravity discharges shall be designed to prevent erosion of

the roadside ditch.

(4). Pump systems:

(a). An outfall from a pumped discharged system shall not

discharge directly into the roadside ditch but shall

provide a stilling manhole or basin for pump system

energy dissipation prior to a gravity discharge.

(b). The entrance velocity into the roadside ditch shall not

exceed three feet (3’) per second.

(c). A maximum level control and return line to the

detention basin shall be provided to limit head build up

and control outflow into the roadside ditch during a

flooding event.

E. A gravity spillway must be provided in addition to the pipe outlet

to protect structures from flooding in the event the capacity of the

basin is exceeded.

SECTION 6.04 - OWNERSHIP AND EASEMENTS

1. Private Facilities

A. Submission of pump system specifications and a written

operating plan that defines how the pump(s) will be

controlled to avoid overloading the existing system is

required when pump discharge outfalls into a roadside ditch.

This information shall be included in the plan detail sheets.

B. A maintenance work area of twenty feet (20’) in width

surrounding the extent of the detention area shall be

provided. Permanent access easements and necessary utility

easements and parking lots may be included as a portion of

this twenty-foot (20’) width as determined by the County

Engineer.

C. Notice of Detention Requirements Form

(1). Blank forms are available upon request.

(2). The “Notice of Detention Requirements” forms shall

indicate the party responsible for maintenance of the

detention facility.

(3). A signed and notarized “Notice of Detention

Requirements” shall be filed in the Harris County

Clerk’s Office, Real Property Records.

(4). Once filed, the form becomes a legal document

attached to the property in perpetuity.

(5). If conditions change and the detention system is no

longer required, the Harris County Engineering

Department will notify, in writing, the Harris County

Clerk’s Office, Real Property Records. Such notice shall

unencumber the property from the previously recorded

“Notice of Detention Requirements” form.

D. Any facility serving a single-family residential subdivision

with 14 or more lots and private streets, shall have the

detention facility maintained by a political subdivision of

the state.

2. Public Facilities.

A. Detention facilities will be accepted for maintenance by the Harris

County Flood Control District in cases where public drainage is

being provided and the facilities meet minimum requirements for

acceptance.

B. A maintenance work area of thirty feet (30’) in width surrounding

the detention area must be provided. Up to 10 feet of public right-

of-way may be included as a portion of the 30-foot width.

C. A dedication of easement shall be provided by plat or by separate

instrument.

D. For wet bottom basins, the minimum wet surface area shall be one

(1) acre unless it incorporates storm water quality features such as

wetland areas.

E. Any facility draining water from public streets shall be

maintained by a governmental body such as a municipal utility

district or HCFCD.

SECTION 6.05 – SUBMERGED STORM SEWERS

The use of submerged storm sewers should be avoided unless it is part of a

storm water quality feature/amenity lake system. For the purpose of these

regulations, storm sewer systems are not considered submerged where only

the outlet pipe from the last manhole entering a storm water quality/amenity

lake system is below static water surface. In this case, storm sewers shall

meet the following conditions:

Permanent Access Easements/Private Streets/Storm Sewers

1. Incorporate methods to drain the system in case of repairs. Methods

include specifying locations of cofferdams, specifying portable pump

equipment, and providing a sequence that would result in being able to

drain any portion of the storm sewer within 3 days with the longest

allowable time being 5 days.

2. In order to reduce the possibility of mosquito breeding, a system shall

be designed such that sections of storm sewer are dry or hold a

minimum of 3 inches of water and are continuously connected to the

lake feature.

Public Streets/Storm Sewers

1. Incorporate a sluice gate system into design so that the lake can be

drained by gravity. If desired, an additional sluice gate may be added

to isolate the storm sewer system from the lake.

2. Design the sluice gate system such that upon opening, the lowest

portion of the storm sewer will drain dry by gravity within 3 days with

the longest allowable time being 5 days.

3. If equipped with a sluice gate designed to isolate the storm sewer, the

manhole adjacent and upstream of the sluice gate must have a sump of

sufficient depth to allow for pumping the system dry.

4. Provide an Interlocal Agreement, in a form acceptable to the County

Attorney, between the utility district or other political subdivision of

the State and the County indicating the following:

a) The entire system shall be covered by a drainage easement

dedicated to the public.

b) The utility district will accept the dedication of the sluice gate

system for maintenance.

c) The utility district will make available to the County all

complaints regarding the storm sewer system and the utility

district’s repair and maintenance records.

d) The utility district agrees not to damage any pavement or storm

sewer in its maintenance of the sewer system.

5. In order to reduce the possibility of mosquito breeding, a system

shall be designed such that sections of storm sewer are dry or hold

a minimum of 3 inches of water and are continuously connected to

the lake feature.

The following additional design requirements apply to submerged storm sewer

systems.

a) The hydraulic gradient shall be calculated using the static lake

level as the starting water surface elevation.

b) All storm sewer pipe shall be reinforced concrete pipe ASTM, C-

76, Class III with joint conforming to ASTM C443 with rubber

gaskets conforming to ASTM, C1619.

c) All storm sewers shall be encased in cement stabilized sand in

conformity with City of Houston drawings, 02317-02, 02317-03,

02317-05, 02317-06, and 02317-07, as appropriate.

d) Submerged storm sewer systems are not allowed within the

rights-of-way of major thoroughfares.

SECTION 6.06 – LOW IMPACT DEVELOPMENT AND GREEN

INFRASTRUCTURE

A Low Impact Development (LID) or Green Infrastructure (GI) technique

may be utilized to address drainage and storm water quality requirements

provided:

1. The proposed LID or GI technique conforms to the Harris County Low

Impact Development & Green Infrastructure Design Criteria for Storm

Water Management (Design Criteria) as adopted by Commissioners’

Court; and

2. Prior to submitting plans for acceptance, the proposed LID or GI

technique must be reviewed in a pre-project meeting in accordance

with the Design Criteria.

SECTION 7 - PAVING

SECTION 7.01 – PAVING DESIGN REQUIREMENTS

The following design requirements are applicable to all pavement that is

designed and constructed under Harris County jurisdiction by the development

community.

SECTION 7.02 - DESIGN REQUIREMENTS

The following design requirements are applicable to pavement within the

Harris County street right-of-way:

1. PAVEMENT WIDTH– The width shall be in accordance with the

following Table 7.1, “Roadway Classifications and Section

Requirements” and the “Geometric Design Guidelines for Subdivision

Streets” as most recently adopted by Harris County Commissioners’

Court.

2. All proposed major thoroughfares within unincorporated Harris

County shall meet the current design criteria as promulgated by the

County Engineer. The City of Houston Major Thoroughfare Plan, all

other municipalities’ Major Thoroughfare Plans, and the Thoroughfare

Amendment Study for Unincorporated and Non-ETJ Areas of Harris

County, Texas as adopted by Harris County Commissioners Court will

be used to determine when a roadway is classified as a major

thoroughfare.

3. Major thoroughfare intersections, including intersections between

local/collector streets with major thoroughfares, shall not exceed 1%

algebraic grade difference. Transitions to achieve that grade must be

made in advance of the intersection and beyond the intersection.

Proposed top of pavement elevations shall be provided along the

gutter lines and pavement centerlines to show conformance with

grade requirements. An “As-Built” record drawing shall be provided

to Harris County prior to scheduling an inspection.

4. The engineer shall design and prepare plans for the full boulevard

within the limits of all proposed major thoroughfares. Developer’s

requirements is to only build one half of the boulevard and entire

drainage system including any required detention for the full

boulevard unless location specific needs dictate an alternate

consideration approved by the County Engineer.

5. Centerline of swales used to drain the unimproved half boulevard

section shall be placed to drain to future inlets which must be

constructed to stage one with type E inlets.

Table 7.1 Roadway Classifications and Section Requirements

*A waiver to this requirement may be requested if onsite parking is proposed.

A site plan for the reserve development indicating the type of facilities and

number of parking spaces proposed is required to be submitted with the

preliminary infrastructure plan submittal. Harris County will make a

determination if the proposal is satisfactory. If acceptable, a letter of

certification from the developer stating that the required number of parking

spaces will be provided in connection with the development of the reserve is

required as a condition of signature and approval of the infrastructure plans

Notes:

1. 4x12 curb section shall only be approved on streets where single family

structures are taking direct primary access.

2. Alternative paving sections may be considered and approved by the

County Engineer for master planned, mixed-use developments.

Land Use on Both Sides of

Right-of-Way (R.O.W.)

Roadway

Classification

Portland Cement Concrete

Single

Paving

Section

Double Paving Section Major Thoroughfare

Width Curb Width Curb Width Curb

Single family Residential on

both sides of R.O.W.

Local 28’ (B-B) 6” or 4” x 12 2/25’ 6” or 4” x 12

Single Family Residential

Reserve Restricted to

Landscape or pocket parks

less than one acre

Local 28’ (B-B) 6” or 4” x 12

6”

2/25’ 6” or 4” x 12

6”

Single Family Residential

Detention Pond or Amenity

Lake

Local 28’ (B-B) 6” or 4” x 12

6”

2/25’ 6” or 4” x 12

6”

Single Family Residential

Reserve Restricted to

Recreation/Open

Collector 41’ (B-B)* 6” or 4” x 12

6”

2/25’ 6” or 4” x 12

6”

Single Family Residential

Unrestricted or Restricted to

Commercial or Industrial

Collector 41’ (B-B) 6” or 4” x 12”

6”

2/25’ 6” or 4 ”x 12”

6”

25’ (B-B) 6” only

Restricted Reserve to

Commercial or Industrial on

both sides of R.O.W.

Collector 41’(B-B) 6” 2/25’ 6” 25’ (B-B) 6” only

Table 7.1 Continued below:

Land Use on Both Sides of right-of

Way (R.O.W.) Roadway

Classification

Single Paving

Section with

Roadside Ditches

Double Paving Section

with Roadside Ditches

Asphaltic Concrete

__________________

Single Paving Section

with Roadside

Ditches

Width Width Width

Single family Residential on both

sides of R.O.W.

Local 22’ (E-E) with 6’

shoulders

2/24’ (E-E) with 6’

shoulders

22’ (E-E) with 6’

shoulders

Single Family Residential

Reserve Restricted to Landscape or

pocket parks less than one acre

Local 22’ (E-E) with 6’

shoulders

2/24’ (E-E) with 6’

shoulders

22’ (E-E) with 6’

shoulders

Single Family Residential

Detention Pond or Amenity Lake

Local 22’ (E-E) with 6’

shoulders

2/24’ (E-E) with 6’

shoulders

22’ (E-E) with 6’

shoulders

Single Family Residential

Reserve Restricted to

Recreation/Open

Collector 41’ (E-E) with 6’

shoulders

2/24’ (E-E) with 6’

shoulders

41’ (E-E) with 6’

shoulders

Single Family Residential

Unrestricted or Restricted to

Commercial or Industrial

Collector 41’ (E-E) with 6’

shoulders

2/24’ (E-E) with 6’

shoulders

41’ (E-E) with 6’

shoulders

Restricted Reserve to Commercial

or Industrial on both sides of

R.O.W.

Collector 41’ (E-E) with 6’

shoulders

2/24’ (E-E) with 6’

shoulders

41’ (E-E) with 6’

shoulders

PAVEMENT THICKNESS

A. Local, Collector, Major Thoroughfare

(1). Concrete - The requirements presented in Table 7.2 below

shall be the minimum allowable local, collector,

thoroughfare thicknesses utilizing Portland cement

concrete. These thicknesses were developed considering

both the Portland Cement Association (PCA) design method

(“Design of Concrete Pavement for City Streets”, 1974) and

the American Association of State Highway and

Transportation Officials (AASHTO) method (“AASHTO

Guide for Design of Pavement Structures”, 1993).

Table 7-2. Concrete Thickness for 30-Year Design Life

Roadway

Classification

Concrete Pavement

Thickness, in.

28-day

Compressive

Strength, fc’, psi

Minimum Required Depth

of Stabilization, in.

Local

6 3000 6

Collector

7 3000 8

Major

Thoroughfare

4500

3000

Notes:

1. For major thoroughfares in excess of 30,000 VPD (see

criteria below).

2. For paving design purposes, see definitions for

local, collector, and major thoroughfare as

described in “Section 12 – Traffic” of these

regulations.

(2). Asphalt, Flexible Base – roads shall use a minimum of a six-

inch (6”) stabilized subgrade, eight inches (8”) of base

course, one and one-half inches (1½) hot mixed, hot laid

asphalt. Alternative pavement design may be considered

provided the equivalent structural number is met or

exceeded. Flexible base pavement for all developments,

other than low density, single-family, shall be designed in

accordance with the design parameters in Section 2, below.

B. Major Thoroughfares with an excess of 30,000 VPD on year 15 of

design life, a licensed engineer shall design the pavement thickness

and reinforcement using the AASHTO method and Harris County

Engineering Department specified design parameters. The

pavement thickness and reinforcement design shall be based on a

current soil analysis, stabilized subgrade, roadway use (including

the design lane traffic volume) and life span of the proposed

pavement.

Harris County Engineering Department specified design parameters for

reinforced concrete designs for Major Thoroughfares are:

AASHTO Design

Parameter

Design Value Comments

Drainage Coefficient, C

1.2 Good to excellent, 1%

Excellent, 1% to 5%

Load Transfer Coefficient,

3.2

Jointed, reinforced pavement with

load transfer such as dowels,

specified by detail

Loss of Support, LS 1

Modulus of Rupture, S’

See comment Dependent on required

concrete compressive

strength

=570 psi for f’

=3000 psi

=620 psi for f’

=3500 psi

=660 psi for f’

=4000 psi

=710 psi for f’

=4500 psi

Reliability, R 95%

Initial Serviceability

Index, p

4.5

Terminal Serviceability

Index, p

2.5

Elastic Modulus, E

See comment

Dependent upon required

concrete strength

=3.6x10

psi for f’

=3000

psi

=3.8x10

psi for f’

=3500

psi

=4.0x10

psi for f’

=4000

psi

AASHTO Design

Parameter

Design Value Comments

=4.2x10

psi for f’

=4500

psi

Friction Factor, F

1.8

Lime, lime-fly ash, asphalt

or cement stabilized

subgrade

Harris County Engineering Department specified design parameters for flexible

paving designs based on available traffic data are:

AASHTO Design

Parameter

Design Value Comments

Reliability, R 95%

Standard Deviation, S

0.45

Soil Resilient Modulus, M

30,000 psi Mr = 1500 X CBR; CBR

estimated as 20 for

stabilized subgrade

Drainage Coefficient, m

1.25 AASHTO Table .24 – good

quality drainage (1% - 5%)

– drains within 1 day

Initial serviceability index,

4.2

Terminal serviceability

index, p

2.5

Structural layer

Coefficients

Hot-mixed hot-laid

asphalt surface

material

0.44

Black base 0.34

Cement-stabilized

limestone

0.23

Lime-stabilized

limestone

0.17

Crushed recycled

concrete

0.14

Raw limestone 0.14

Cement-stabilized earth 0.15

Lime-stabilized or lime-

fly ash stabilized earth

0.11

AASHTO Design

Parameter

Design Value Comments

Minimum acceptable

recommended thickness

Surface course 2 in.

Base course 4 in.

Sub-base course 4 in.

SECTION 7.03 – MATERIALS REQUIREMENTS

The following requirements shall apply to paving subject to the jurisdiction of

the Harris County Engineering Department:

1. The concrete mix design shall be either of the following options:

A. A mix design containing five (5) sacks of cement per cubic yard

with no Fly Ash allowed; or

B. A mix design containing Fly Ash and cement that has cementitious

content of not less than five and one half (5 ½) sacks per cubic yard.

The Fly Ash content shall not exceed twenty-five percent (25%) by

weight.

2. All concrete pavement shall have a minimum design and in place

compressive strength of 3000 psi at twenty-eight (28) days.

3. Concrete for major thoroughfares shall meet the design determined by

the AASHTO design required in Section 7.02 B, above.

4. Minimum reinforcing for Local, Collector, and Major Thoroughfares shall

meet the size, strength, and spacing shown in Table 7.3 following:

TABLE 7.3

REINFORCING STEEL BAR SIZES AND SPACING

FOR VARIOUS PAVEMENT THICKNESS (D) AND WIDTH (W) WITH:

EXPANSION JOINT SPACING = 80 FT (MAXIMUM)

fcc

= 3,000 PSI AND fy = 60,000 PSI

LONGITUDINAL STEEL TRANSVERSE STEEL

PAVEMENT # 4 BARS # 4 BARS

THICKNESS

(IN)

PAVEMENT

WIDTH

(FT)

NUMBER

BARS

SPACING

(IN)

END BAR

SPACING

(IN)

SPACING

(IN)

6 28 17 20.50 4 36

7 25 17 18.25 4 36

7 35 24 18.00 3 36

7 36 25 17.75 3 36

7 37 25 18.25 3 36

7 41 28 18.00 3 36

7 45 31 17.75 3 36

MAJOR THOROUGHFARE

LONGITUDINAL STEEL TRANSVERSE STEEL

#5 BARS #5 BARS

PAVEMENT

THICKNESS

D(IN)

PAVEMENT

WIDTH (FT)

NUMBER OF

BARS

SPACING(IN)

END BAR

SPACING (IN)

SPACING(IN)

10 25 44 18 3 36

10* 25 86 9 3 36

*Applies to major thoroughfare paving with one hundred sixty feet (160’)

expansion joint spacing only.

**Reinforcing steel bar size and spacing for eight inch (8”) pavement thickness

to be designed by the engineer.

Minimum lap length for #4 reinforcing steel shall be twenty-two

inches (22”). Minimum lap length for #5 reinforcing steel shall be

twenty-four inches (26”). For all cold construction joints, use four-

foot (4’), Grade 40 L-bars spaced at 24-inch centers through the

deformed metal strip.

B. Expansion joints in cul-de-sacs and knuckles shall be placed as

shown in Appendix “I”.

5. Asphalt

Hot mix asphalt shall meet the requirements of “Harris County

Standard Specification, Item No. 250 and 340”. (Complete Harris

County Standard Specifications are available online at

www.eng.hctx.net).

6. Base Course Requirements

A. Cement stabilized crushed aggregate base course shall meet the

requirements in “Harris County Standard Specification, Item No.

231” except that Section 231.4 is modified so that the base course

shall be compacted to 95% Standard Proctor Density, ASTM D-698.

B. Hot mix asphaltic concrete base course (black base) shall meet the

requirements in “Harris County Standard Specification, Item No.

250.”

C. Untreated aggregate base shall meet the requirements in Harris

County Standard Specification Item No. 230. Placement

requirements shall be included in the construction plans, maximum

eight-inch (8”) lifts, compacted to 95% Standard Proctor Density,

ASTM D-698.

7. Stabilized Subgrade Requirements

The geotechnical engineer shall provide subgrade treatment recommendations

including type of stabilizer and anticipated application rate (lb/yd

) to develop

the required subgrade density design requirements.

A. Lime-stabilized subgrade shall meet the requirements outlined in

“Harris County Standard Specifications, Item Nos. 220 and 221”.

B. Portland Cement-stabilized subgrade shall meet the requirements

outlined in “Harris County Standard Specification, Item No. 222”.

C. Lime fly ash or fly ash stabilized subgrade shall meet the

requirements outlined in “Harris County Standard Specification,

Item No. 223”.

D. Commercially available products shall meet the requirements of

the manufacturer and the geotechnical engineer and shall be

approved by Harris County Engineering Department.

SECTION 7.04 – SPECIFICATION REQUIREMENTS

1. Pavement shall be constructed in accordance with “Harris County

Standard Specification, Item No. 360”, as modified below, for all

privately funded local and collector roadway projects.

A. Section 360.13, is hereby modified to allow the use of a metal

center strip in lieu of saw cutting the center longitudinal

contraction joint.

B. Section 360.8, is hereby modified to allow the use of wood forms

for six-inch (6s) and seven-inch (7s) pavement sections. The

bottom flange of steel forms shall be two inches (2”) or more. If

other commercially available types of forms are used they shall

be installed in accordance with the manufacturer’s suggested

method and meet the approval of the design engineer and Harris

County Engineering Department.

C. Section 360.10,11, and 12, is hereby modified to allow placement

at contractor’s responsibility based upon equipment sequence

utilized in accordance with recommendations and practices of

ACI 304.

D. Section 360.19 Deficient Pavement Thickness, is hereby

modified as follows:

It is the intent of Harris County to receive and accept streets and roads into

the County’s System of Maintained Roads that are constructed in strict

conformity with the paving thickness shown on the approved construction

plans.

Pavement that is constructed and cored in accordance with this specification

shall be acceptable if the measurement of any core is not deficient by more

than 0.30 inches from the thickness shown on approved construction plans.

If a core shows the pavement to be deficient in thickness by more than 0.30

inches but less than 0.5 inches, the following procedure may be followed:

1. Additional cores for deficient pavement thickness will be taken at

ten-foot (10’) longitudinal intervals and at random locations

transversely on each side of the deficient core until a core is taken that

is acceptable. If the new cores on either side of the deficient core are

acceptable and the average of the three cores is not more than 0.30

inches less than the original plan thickness, the pavement is acceptable.

2. If the average of the cores in (1), above, is not acceptable, then

additional cores shall be taken until an acceptable core is found on each

side of the original deficient core. All concrete between the two

acceptable cores shall be removed and replaced to the centerline joint.

3. All cores shall be from the same pavement pour.

Any core that is deficient by 0.5 or more inches is unacceptable. If a core is

unacceptable then take additional cores out of the same pour on each side of

the deficient core at ten-foot (10’) intervals until the pavement thickness is

found to be acceptable as stated above. All concrete between the two

acceptable cores shall be removed and replaced to the centerline joint.

A. All references to Harris County Specification requirements

contained in this document pertain to the technical provisions of

the specifications and not to the measurement and payment

provisions therein.

B. Section 360.12 is hereby modified to allow use of fly ash in lieu

of retarder up to a temperature of 97q if approved.

Major thoroughfares shall be constructed in accordance with Harris County

Standard Specification 360.12.

SECTION 7.05 – GEOMETRIC REQUIREMENTS

1. Curb and Gutter Sections

A. The minimum gradient on gutters shall be 0.30 percent.

B. The maximum drop of grade tangents from opposite directions to

a common inlet shall be 1.5 feet.

C. The maximum allowable curb run to an inlet shall be seven

hundred feet (700c) in one direction for residential streets and

three hundred feet (300c) in one direction for major

thoroughfares or streets within commercial developments.

D. There shall be a minimum one percent (1%) fall around

intersection turnout for a minimum radius of twenty-five feet

(25c). The grade for larger radius shall be determined on an

individual basis.

E. Vertical curves shall be installed when algebraic difference in

grades exceeds one percent (1%). Elevations shall be shown at

ten-foot (10c) intervals through vertical curves. A minimum

differential of 0.03 feet (0.03’) on ten foot (10’) intervals shall be

maintained by altering the calculated elevations.

F. The required radius of cul-de-sac pavement is as follows:

(1). Residential radius shall be a minimum of forty-two feet

(42c) to face of curb, and

(2). Commercial radius shall be a minimum of fifty feet (50c) to

face of curb.

G. Unless otherwise directed by the County Engineer, when a curb

and gutter intersects a drainage ditch, the grade of the gutter

must be above the designed water surface of the ditch in

accordance with requirements of the Harris County Flood Control

District.

H. The minimum grade for cul-de-sac shall be 0.60 percent along

gutter.

I. All major thoroughfares with a center line radius of lanes or

rights-of-ways less than two-thousand feet (2000’) will require a

variance that shall be reviewed and approved by the County

Engineer.

J. Super-elevation should not be used except with prior approval by

the County Engineer. Where super-elevation is used, it should be

based on sound engineering practice and in accordance with the

latest edition of AASHTO’s, “A Policy on Geometric Design of

Highways and Streets.”

K. For boulevard sections, the amount of cross slope over the

pavement section shall be shown on the plans. The usual cross

slope is one-fourth inch (1/4s) per foot from curb line to curb line,

and one-eighth inch (1/8s) per foot for turn lanes and esplanade

crossovers.

L. For streets with single paving sections, the amount of cross slope

over the pavement section shall be in accordance with Harris

County Drawing S/D-1, “Subdivision Pavement Standards.”

M. A minimum gradient of 0.40 percent around the longest radius is

required on an L-type street intersection.

N. All grades shall be laid to match the top of the curb of an existing

inlet.

O. When the curb grades are not laid below the natural ground, fill

lines shall be shown on the plans and shall be of a sufficient

height to ensure a minimum of three-eighths inch (3/8s) per foot

transverse slope toward the curb from the property line between

a point two feet (2c) outside the right-of-way and the top of the

curb. If this type fill is required and the pavement is adjacent to

a non-participating property owner, fill easements from this

property owner must be obtained and filed. A copy of the

recorded easement document shall accompany the final plans.

P. All grades shall be labeled for all top of curbs except at railroad

crossings. Centerline grades are only acceptable for approved

streets with ditch sections.

Q. Gutter elevations are required for vertical curves where a

railroad track is being crossed.

R. The gradient for tangents to vertical curves at railroad crossings

shall be a maximum of three and one-half percent (3.5%) and four

percent (4%) at bridges, box culverts, and pedestrian tunnels.

S. Where railroad crossings are not at right angles to the pavement

slab, vertical curves should be calculated for each curb line and

should be posted at ten-foot (10c) intervals in the profile.

T. Valley Gutters are not permitted.

2. Roadway Sections with Ditches

A. The minimum grade on ditches shall be one percent (1.0%). If

ditches exceed 4 feet in depth, with side slopes steeper than 5 to

1, guard rails shall be required or ditches piped unless an

alternative design meeting the intent of this section is submitted

and approved.

B. The ditch shall be designed to handle runoff as determined in

Section 6.02 “Design Requirements”, above.

C. The side slopes of ditches shall not be steeper than a ratio of 3:1

for unimproved ditches. Steeper slopes may be allowed when

existing right-of-way is limited or other construction features

dictate the design. Prior written approval by the Harris County

Engineering Department shall be obtained for steeper slopes.

D. All culverts shall be designed to carry ditch discharge. The

minimum culvert size shall be eighteen inches (18”). All

driveways shall have culverts or bridges.

3. Curbs

A. The standard curb height for residential streets is either the

standard six-inch (6”) curb or a four-inch by twelve-inch (4”x12”)

roll-over curb configuration. Islands shall be constructed only

with a six-inch (6”) standard curb height in accordance with

Harris County Drawing S/D-1, “Subdivision Pavement Standards.”

B. Curbs are to be decreased from six inches (6s) to two inches (2s)

in ten feet (10c) when approaching railroad tracks, an existing

roadway without curbs, or channelized turn lanes.

4. Sidewalks and Driveways

A. All sidewalks and driveways shall conform to the latest revision

of the “Regulations of Harris County for the Construction of

Driveways and Culverts on County Easements and Rights-of-Way”

and in accordance with the requirements of the Texas Department

of Licensing and Regulation (TDLR).

B. Paved median noses shall be six inches (6”) thick with surface

colored black for concrete pavement and uncolored for asphalt

pavement, a minimum of six feet (6’) deep measured from the end

of the median nose and the curbs are at least four feet (4’) in

width face to face. This requirement is imperative for all median

noses.

C. If sidewalks are proposed, curb ramps shall be provided to

connect to adjacent sidewalks and shall be designed in accordance

with the requirements of the Texas Department of licensing and

Regulations (TDLR) and standard details as promulgated by the

County Engineer.

5. Requirements for Intersections, Turnouts, Transitions, and

Thoroughfares

A. At a “T” intersection with a street that has not been improved to

its ultimate width, concrete pavement should be stopped either

at the right-of-way line or the end of the curb return, whichever

would require less concrete removal at a future date.

B. When roadway turnouts are placed where an existing cross street

intersects, the turnout should be sized to fit the ultimate

pavement width and then transitioned to the existing roadway

utilizing the same materials as exist on the existing road/street.

The length of transition shall conform to “Geometric Guidelines

for Subdivision Streets, Harris County, and City of Houston,” (and

any subsequent revisions thereto) as adopted by Commissioners’

Court on July 28, 2009, and the latest edition of the “Texas

Manual on Uniform Traffic Control Devices” (TMUTCD) with

Revisions.

C. When paving only one (1) side of a proposed divided

thoroughfare, all left turn lanes and median crossovers in the

one-half (1/2) of the right-of-way where the roadway is being

paved shall be paved to the center line of the street right-of-way

except at street intersections where turnouts should be

constructed for both halves of the boulevard.

D. When meeting an existing concrete street at right angles, the

existing street shall be saw cut in a V-shape extending from the

curb returns to a point where the center line of the proposed

pavement intersects the quarter point of the existing street in

order to create a crowned intersection. In the event that this

construction would cause an excessively rough riding condition

which would make adequate control of the vehicle difficult, a

special design will be considered to eliminate this condition.

E. All traffic signs, striping, channelization devices, etc., must

comply with the latest edition of the “Texas Manual on Uniform

Traffic Control Devices” (TMUTCD) with Revisions.

F. Prefabricated pavement markings on major thoroughfares and

major thoroughfare modifications shall be placed in accordance

with Harris County Standard Specifications, Item Nos. 666 and

669.

6. Miscellaneous Paving Requirements

A. If driveways are to be constructed with the paving project, show

the driveways on the plans and post a center line for the driveway

at the property line with elevation for each drive.

B. Private streets shall be treated as if they were driveways, and the

sidewalk area should be honored with no curb extending through

this area unless the private street is constructed to public street

standards, including curb ramps.

C. Load transfer devices shall be placed at the end of all concrete

streets and protected from corrosion.

D. All concrete that must be removed shall be removed either to an

existing expansion joint or a sawed joint.

E. Crest vertical curves shall provide sight distance in accordance

with the design speed; however, a minimum forty-five (45) MPH

sight distance must be maintained for all major thoroughfares,

and forty (40) MPH sight distance must be maintained for all

other crest vertical curves

F. Barricades which meet the Harris County requirements (Type III)

must be placed at the end of all dead-end streets that do not

terminate in a cul-de-sac.

G. Prior to final acceptance of the improvements by Harris County,

the owner of the development must furnish and install the street

name signs for all intersections. The street name signs shall be

standard Harris County type signs having a green background

with white lettering and complies with the “Texas Manual on

Uniform Traffic Control Devices” (TMUTCD) with revisions

required.

H. A letter of agreement from the entity approving the construction

plan crossing is required when paving is placed over a

transmission pipeline.

I. Horizontal tie bars are required when meeting concrete pavement

that has no exposed steel and further:

(1). The tie bars shall be #6 bars, twenty-four inches (24s) long,

twenty-four inches (24s) center to center, embedded twelve

inches (12s), and epoxied; and

(2). As an alternate to (1) above, the existing pavement may be

saw cut and removed to expose a minimum of twelve inches

(12s) of steel (longitudinal) to the new construction with an

equivalent cross section area of steel equal to the proposed

pavement steel.

J. All guidelines set forth in the latest edition of “Texas Manual on

Uniform Traffic Control Devices” (TMUTCD) with Revisions shall

be strictly followed.

K. “Cold” joints in pavement are prohibited.

L. Pavement marking and sign placement details shall be shown on

the plan and profile sheets or on separate plan sheets.

SECTION 8.0 – STRUCTURES AND BENCHMARKS

1. The inclusion of bridges or other ditch type crossings may be required

as part of a project in order to maintain a smooth flow of vehicular

traffic through any given area. In the event uncertainty exists

concerning whether or not a bridge will be required, it is advisable to

contact the Harris County Engineering as soon as possible so that the

issue can be resolved while the project is in the planning stage.

For all bridges and similar crossings that are to be constructed within

the jurisdiction of Harris County, the following requirements shall

apply:

A. All bridges and box culverts to be designed to minimum HL-93

loading or AASHTO “LRFD Bridge Design Specifications” as

applicable load design.

B. Bridge Widths

(1) Where there are no curbs on the approach pavement to the

bridge, the width of the bridge (face to face of curbs) shall

be out to out distance of the approach road pavement edges

plus two feet (2’) each side, plus the walk or walks. The

sidewalks shall be four-foot (4’) clear width type.

(2.) Where there are curbs on the approach pavement to the

bridge, the width of the bridge (face to face of curbs) shall

be the same as the distance between curb faces on the

approach road. The sidewalks shall be six-foot (6’) clear-

width type.

C. Individual one way traffic bridges on median boulevards shall

have one walk on the outside of either side of the bridge and two

way traffic bridges shall have a walk on each side of the bridge.

D. All bridges shall be of reinforced concrete design unless specific

application require other materials and then only with prior

approval of the Harris County Engineering Department.

E. All bridge railings shall be galvanized or stainless steel on

reinforced concrete parapet walls.

F. All galvanized Flex Beam Guard Rails shall be designed and

constructed in accordance with the Harris County Engineering

Department drawing titled “Flex Beam Guard Rail Detail”.

G. All design and construction shall be in conformance with “Harris

County Standard Specification Item No. 420, Concrete Structures”

and all other applicable Harris County specification items.

H. Where culverts are used as a bridge, the headwall shall be of a

sufficient height to allow construction of the guardrail and sidewalk

at the elevation of the roadway.

2. The inclusion of a new permanent benchmark is required for the

following projects and shall be clearly indicated on the construction

plans for the proposed location:

A. All new or substantially repaired bridges that are designed for

public vehicular traffic. The benchmark shall be located at the

midway point on the downstream side of the bridge.

B. New residential subdivisions with the following exceptions:

(1) Where the entire subdivision is located further than

one mile outside of the current Flood Insurance Rate Map

1% (100–year) floodplain boundary.

(2) Where the subdivision is located within one mile of

an existing Harris County reference mark and that mark

has been recovered within the past 365 days. Station

recovery data forms are available through the Harris

County website: http://www.harriscountyfrm.org.

(3) Permanent physical markers shall be provided so

each lot owner has access to, or visibility of, the

Floodplain Easement, if any, on a lot.

New benchmarks shall be located on top of the concrete over a

BB inlet, or on the concrete at the nose of a median in the center

of the road.

The benchmark shall be established upon a permanent structure,

or may be set as a monument, and shall be readily accessible

and identifiable on the ground.

All required monuments, markers and benchmarks shall be in

place prior to the County’s acceptance of any street

improvements.

C. Refer to Appendix J for requirements for setting new

benchmarks, submittal and acceptance procedures.

SECTION 9.0 - TESTING REQUIREMENTS

SECTION 9.01 GENERAL

1. All construction materials shall be tested and monitored by an A2LA or

AASHTO accredited laboratory.

2. All construction materials shall be tested and monitored in accordance

with provisions referenced in Section 7.04.

3. Any engineering technician performing testing in accordance with these

rules shall be proficient for the type of testing required as deemed by the

engineer-in-charge of the accredited laboratory.

4. Upon completion but prior to the acceptance of the work by Harris County

Engineering Department, the accredited materials engineering

laboratory shall submit to the Harris County Engineering Department a

written statement of substantial compliance sealed by a professional

engineer licensed in the State of Texas. The written statement of

substantial compliance must acknowledge that all construction materials

and operations used in the project were tested and inspected by

accredited laboratory and that they comply with all the specifications

applicable to the project.

SECTION 9.02 - BEDDING AND BACKFILL

1. The testing of materials used for bedding and backfill of storm sewers

as well as other utility located underneath or within one-foot (1’) of

subgrade shall be conducted to ensure compliance with “Harris County

Standard Specification No. 430” and the project specifications.

2. In construction applications where utilities under the pavement on

knuckles and/or cul-de-sacs exist, a special geotechnical note shall be

placed on the geotechnical certification page detailing the method of

stabilization and backfill used to meet Harris County Standard

Specifications for these applications.

SECTION 9.03 - SUBGRADE TESTING

1. All paving subgrade shall be proof-rolled after the roadway has been cut

to grade. The Design Engineer, Accredited Laboratory, or their

designated representative shall monitor proof-rolling operations and

shall determine whether remediation of weak areas is required before

subgrade treatment. If remediation is required, the Design Engineer or

Accredited Laboratory shall provide recommendations for remediation.

The Design Engineer shall determine equipment that is suitable for use

during proof-rolling.

2. Samples of the paving subgrade shall be taken to verify the applicability

of the recommended stabilization type and quantities. The Accredited

Laboratory shall determine the frequency of sampling. The Accredited

Laboratory shall confirm that the stabilizer type and application rate

provided in the plans and specifications is appropriate or shall provide

the appropriate stabilizer type and application rate based on laboratory

testing of the paving subgrade.

3. Density tests shall be performed every 300 linear feet of chemically

treated subgrade. Closer spacing for density testing may be required to

verify conformance with project specifications.

4. In the event of rainwater standing on the subgrade after densities are

made or other conditions beyond the contractor’s control, and if the

Design Engineer deems that the subgrade condition has been adversely

affected, proof rolling of the subgrade will be required if reinforcing

steel has not been placed. In the event that reinforcing steel is present,

in-place densities will be performed; however, the Design Engineer may

request that the steel be removed and the subgrade subjected to proof-

rolling.

5. A minimum of three (3) in-place density tests per street are required.

6. The contractor is required to have copies of treated subgrade density

test reports in his/her possession at the construction site at the time of

placement of base material. The test date shall be clearly marked on

the test reports.

SECTION 9.04 - FLEXIBLE BASE

1. All base material shall be from an approved Texas Department of

Transportation (TxDOT) supplier or supplier approved by the Design

Engineer.

2. A minimum of three (3) density tests per street are required to verify

conformance of compaction to the project specifications.

SECTION 9.05 - SURFACE COURSE

1. All surface course material shall be provided from an approved TxDOT

supplier or supplier approved by the Design Engineer.

2. Testing shall be performed through asphalt cores to verify compaction

criteria outlined in the project specifications is met.

SECTION 9.06 - CONCRETE PAVEMENT

1. All concrete shall be provided from an approved TxDOT supplier or

supplier approved by the Design Engineer.

2. The testing Laboratory shall review the submitted concrete mixture

proportions to ensure the requirements of the project specifications are

met.

3. A minimum of four (4) test cylinders shall be made for each 125 cubic

yard, or portion thereof, placed each day. Samples shall be taken in

accordance with ASTM C 172 and molded and cured in accordance with

ASTM C 31. Field tests including measurement of ambient temperature,

concrete temperature, slump, and air content shall be made in accordance

with the appropriate ASTM test methods, where applicable.

4. All test specimens shall be prepared in accordance with ASTM C 617 and

tested in accordance with ASTM C 39. Two (2) specimens shall be tested

at seven (7) days and two specimens shall be tested at twenty-eight

(28) days. The acceptance test results shall be the average of the two

specimens tested for each age interval. If one specimen in a test age

indicates evidence of improper sampling, handling, molding or testing,

it shall be discarded and the strength of the remaining specimen shall

be considered the test result. Should both specimens in a test interval

show any of the aforementioned defects, Harris County may request

that cores of the pavement placed in the affected area be re-taken.

5. Additional test specimens may be required due to concrete placing

conditions or for adequately determining the strength of concrete when

early opening of the paving to traffic is necessary and/or desirable.

SECTION 9.07 - CONCRETE CORES

1. Once the pavement has been in place for a minimum of fourteen (14)

days, one core shall be taken for each 1,000 square yards of pavement

or portions thereof with a minimum of one core on each street. Cores

shall be taken alternately in each one-half section of the pavement. The

Design Engineer or the Testing Laboratory Engineer shall select

locations of the cores.

2. All cores shall be broken at twenty-eight (28) days in accordance with

ASTM C 42. Each core shall meet the minimum compressive strength

requirement outlined in the project specifications. If a core fails to

meet the minimum strength requirement, additional cores may require

testing to meet the aforementioned testing requirements.

3. See Section 7.04 (1)(K), above for a discussion of pavement thickness

verification by concrete cores.

SECTION 9.08 - STRUCTURES

1. Testing for bridges and structures shall be in accordance with the project

specifications.

SECTION 10 - INSPECTIONS

SECTION 10.01 - CONSTRUCTION INSPECTION

The construction of improvements shall be conducted under the supervision of

a licensed engineer who shall ensure that work is performed in accordance with

the approved plans. Monitoring shall be performed by the following:

1. The Design Engineer shall provide a qualified onsite inspector throughout

the construction project for all significant operations.

2. A construction materials technician proficient in the type of testing being

performed as deemed by the engineer-in-charge of the accredited

laboratory.

3. An inspector from Harris County.

SECTION 10.02 - NOTICE OF START

The contractor shall notify the Harris County Engineering Department in

writing (emails and facsimile acceptable) a minimum of twenty-four (24) hours

in advance of the work commencing on the project. The notice shall include the

development permit number issued under the “Regulations of Harris County,

Texas, for Floodplain Management.” Failure to follow these requirements may

result in the County not accepting the paving and drainage facilities for

maintenance upon completion.

SECTION 11 - ACCEPTANCE OF IMPROVEMENTS WITHIN

SUBDIVISIONS

SECTION 11.01 – ACCEPTANCE PROCEDURES

A project is eligible for initial inspection at such time as the pavement and

drainage facilities have been completed and the subdivision plat and required

right-of-way or easement instruments have been recorded in the Official

Public Records of Harris County.

To schedule an initial inspection and allow homebuilders to obtain

development permits in accordance with the Regulations of Harris County,

Texas for Floodplain Management, the Engineer of Record shall submit the

following:

1. A completed “Request for Initial Inspection Form” as promulgated by

the County Engineer. An engineer may submit the request

electronically via the on-line submittal process. The form shall include

the engineer’s, contractor’s, and developer’s e-mail address for contact

purposes.

2. A physical copy of the approved plans for the project. These plans

shall be stamped record drawings, sealed by a licensed engineer and

shall have the following statement. “This project is constructed in

general conformance with these plans and elevations on these plans

represent what was constructed within engineering tolerances.” In cases

where Developer builds both halves of a major thoroughfare, the

stamped record drawings shall cover both halves.

3. A “Statement of Substantial Compliance Form” as promulgated by the

County Engineer demonstrating the project met all testing and

performance requirements. An engineer may submit the request

electronically via the on-line submittal process.

4. Two physical copies of the recorded plat to scale.

5. A copy of the development permit.

6. A copy of the Financial Surety Worksheet and receipt.

Each homebuilder may obtain one (1) permit for a model home prior to the

initial inspection being scheduled and the requirements above being

submitted.

When receiving the package and request for initial inspection, Harris County

shall issue a receipt indicating what items were received and the date they were

received. The online system will be updated by the next business day after

receiving the items. Once all items are received, the online system will indicate

the date of package completion beginning the 10 day review process. Then

Harris County shall respond by one of the following:

1. Determining the package is complete, scheduling the initial inspection,

and releasing development permits. No provision in the regulations

releases the project parties from meeting Harris County’s minimum

criteria as adopted in said regulations.

2. Rejecting the package and notifying all parties of required corrections.

Upon the earlier of (1) verification that the submittal documents meet all of

Harris County’s minimum criteria (2) the passage of 10 business days from

package receipt without a rejection or return of the package, homebuilders may

obtain development permits, provided that such permits are otherwise

authorized in accordance with the Regulations of Harris County, Texas for

Floodplain Management. Upon completion of the inspection, the County

Engineer shall issue a punch list indicating any items that must be addressed

prior to the start of the one-year performance period. The engineer must apply

for re-inspection and pass the initial inspection within 90 days of the original

inspection date. If the engineer has not requested and passed the initial

inspection within 90 days of the original inspection date, the County Engineer

may, in the interest of the safe, orderly, and healthful development of the

unincorporated area of the county and the promotion of the health, safety,

morals and general welfare of the county’s residents, suspend the issuance of

any or all County permits in regard to the subdivision until the initial inspection

has been requested and passed. Any inspection requests after 90 days of the

previous inspection shall be subject to a complete re-inspection of all facilities.

The County will schedule re-inspections within two weeks after receiving a

request. Should the County fail to meet any of the time frames outlined in this

section, an additional day will be added to the 90 day time frame for every day

the County missed the deadline. Once all paving and drainage items are

corrected as well as any safety related items, the County Engineer shall issue a

Letter of Substantial Completion indicating the improvements appear to meet

the approved plans and specifications for the project and specifying the date

the project will be eligible for final inspection and acceptance for County

maintenance. This date will be one calendar year after the date of the “Passing

of the Record Drawing Inspection”.

To schedule a final inspection, an engineer shall submit the following:

1) Submit the request for inspection electronically via the on-line

submittal process

2) The developer’s executed “Directive for Financial Assurance Form,”

as promulgated by the County Engineer. This form indicates if the

developer wishes the County to release or retain the submitted

financial assurance. Should this directive indicate the developer’s

wish that the County retain the submitted financial assurance, the

developer shall be responsible for latent defects only. Should this

directive indicate the developer’s wish that the County release the

submitted financial assurance, less the administrative fees, the

developer will be responsible to fix all deficient items. An engineer

may fulfill this obligation by submitting the request electronically

via the on-line submittal process.

Upon receipt of the above items, the County Engineer shall schedule an

inspection notifying the applicable Precinct representative, developer,

engineer, and contractors of the scheduled inspection date via e-mail.

After completion of the inspection and any subsequent re-inspections, the

County Engineer shall do one of the following in regard to any Financial

Surety consisting of cash, provided that the funds have not been forfeited to

the County pursuant to a Directive for Financial Assurance Form:

1. Recommend acceptance and authorize release of the financial

assurance funds minus the administrative portion in their entirety.

2. Recommend retaining the entire submitted financial assurance funds

and not accepting the infrastructure due to material defects in the paving

and/or drainage improvements constructed by the developer. If this

occurs, the County Engineer shall refer the matter to the County

Attorney for legal action providing specific evidence.

Failure to submit the “Request for Final Inspection Form” and the “Directive

for Financial Assurance Form” within forty-five (45) days after the one-year

anniversary date of the “Passing of the Record Drawing Inspection Date”

shall constitute a failure to complete the roads, streets and drainage

requirements in accordance with these regulations and within a reasonable

time. This shall be considered a violation of a condition of the financial

surety, resulting in a hold being placed on the subdivision for additional

permits and a referral to the Harris County Attorney for further action.

Failure to complete and pass all inspections within six (6) months after the

one-year anniversary date of the “Passing of the Record Drawing Inspection

Date” shall constitute a failure to complete the roads, streets, and drainage

requirements in accordance with these regulations and the financial surety

will be forfeited to Harris County. Harris County may seek further action

through the Harris County Attorney’s Office to bring the subdivision into

compliance.

SECTION 11.02 - INSPECTION AND RE-INSPECTION FEES

A re-inspection fee in the amount of $1,000.00 shall be charged prior to

scheduling the inspection if any of the following events occurs:

1. An inspection is scheduled when the work proposed on the plans is not

completed in its entirety unless such partial inspection is specifically

approved prior to scheduling.

2. A re-inspection is scheduled and upon inspection it is determined that

the deficiencies previously noted have not been addressed.

3. An inspection or re-inspection is cancelled without giving three (3)

working days notice unless affected by severe weather.

In order for a project to be considered ready for inspection, parties must be

available to open and close manhole lids and inlet plates upon request and all

fire plugs in the upper reaches of the storm sewer system must have been

flushed to demonstrate proper flow prior to the start of the inspection. If fire

plugs are not present or charged, this requirement may be waived. Failure

to do so will result in a $1,000.00 re-inspection fee.

In no case will the developer be held responsible for work covered under the

“Regulations of Harris County for the Construction of Driveways and/or

Culverts” as applicable unless the developer was the permittee. The permittee

under those regulations will be held responsible for deficient work. The

developer will only be held responsible for latent defects if they release the

Financial Surety for deficient work.

SECTION 12 - TRAFFIC

SECTION 12.01 – Traffic Definitions:

1. Major Thoroughfares – Long, continuous facilities that are designed to

carry high volumes of traffic and generally serve as high volume travel

corridors that connect and provide access to commercial, mixed use, and

residential areas.

2. Collector – Roadways that carry moderate volumes of traffic. Collectors

can be classified as major or minor, depending on the type of facilities

to which they are connected, length, type of surrounding land use, and

existing and/or projected traffic volume and characteristics. These

facilities typically have the primary function of carrying traffic from local

roadways or other collectors to intersections with like and/or higher

class facilities.

3. Local – Roadways that carry low volumes of traffic local to a given area.

These facilities are typically very short (less than one (1) mile in length).

Their primary function is to provide access to homes and businesses and,

where applicable, accommodate on-street parking and pedestrian

activities.

SECTION 12.02 – LEFT TURN LANES

Left turn lanes shall be required in the following situations:

1. All signalized intersection approaches along Major Thoroughfares and

Collectors, planned or existing;

2. All unsignalized intersections and driveways along divided Major

Thoroughfares and Collectors, planned or existing;

3. All unsignalized intersections and driveways along undivided Major

Thoroughfares, and Collectors planned or existing;

4. All developments with an overall footprint in excess of five (5) acres

located within 500 feet of the intersection of two or more

thoroughfare facilities (i.e., Major Thoroughfares, and/or Collectors

as defined by the City of Houston Major Thoroughfare and Freeway

Plan);

5. New public or private school construction;

6. Shopping centers and other traffic generators with a lease space in

excess of one hundred thousand (100,000) square feet;

7. Places of worship.

It should be noted that the preparation of a Traffic Impact Analysis is strongly

encouraged for all midsize and large developments. Furthermore, a Traffic

Impact Analysis may be required, as a condition for review and/or acceptance,

if it is determined by the Harris County Engineering Department that the

development has the potential to impact regional transportation facilities

and/or has a regional impact on traffic patterns, such as schools. A traffic

impact analysis is required for the evaluation of requests for variances and/or

deviations from Harris County Design and Development Guidelines. If the

developer or engineer feels a left turn lane is not warranted, he/she shall

submit a Traffic Impact Analysis to support any request for a variance of the

left turn lane.

Turn lanes shall meet the criteria outlined in Section 7 - Paving. The paving

design requirements shall be the same as the adjacent main traveled lane

requirements.

When asphalt roadways are widened to accommodate left and right turn lane

installations, the entire roadway shall be overlaid from beginning to ending of

the widening transitions.

SECTION 12.03 - ROADSIDE SIGNS

Roadside signs shall be in accordance to latest edition of the "Texas Manual on

Uniform Traffic Control Devices" (TMUTCD) with Revisions, and Harris County

Standard Details and Design Specifications.

SECTION 13 - LANDSCAPING

SECTION 13.01 - LANDSCAPE POLICY

The purpose of these Rules is to protect the public, to maintain safe and

efficient operating regulations, and to preserve and maintain the integrity of

Harris County roads and road drainage easements and rights-of-ways, during

the construction, maintenance and/or repair of landscaping or placing of

vegetation.

SECTION 13.02 - USE OF TERMS:

A. “Landscaping” means the placement of trees, shrubs, or plants for the

purpose of beautification of an esplanade(s) or other portion(s) within a

County right-of-way.

B. “Visibility Triangle” means the triangular area adjacent to the

intersection of any street established by measuring a distance of twenty-

five (25) feet for Major Thoroughfare and Collector Street and fifteen (15)

feet for Local Street from the point of intersection of two streets along

the right-of-way of each of the intersecting streets and connecting the

ends of each measure distance to assure adequate visibility sight lines for

vehicular traffic approaching the intersection. In these areas,

landscaping shall be no greater in height than thirty (30) inches above

top of adjacent curb or centerline of pavement when allowed to grow to

its maximum height.

C. “Specimen Tree” means an exemplary tree of good health and true to

species habit and form, containing a minimum caliper of 1 ½ inches.

D. “Caliper” means the minimum diameter of a tree as measured six (6)

inches above the ambient grade for trees up to and including four (4)

inches in diameter, twelve (12) inches above the ambient grade for trees

having a diameter exceeding four (4) inches but not exceeding eight (8)

inches and fifty-four (54) inches above the ambient grade for trees having

a diameter greater than eight (8) inches.

SECTION 13.03 - CONSTRUCTION ACTIVITY

No person shall enter upon land acquired, claimed or maintained by Harris

County for road and/or road drainage for the purpose of placement or

modifications of landscaping until the County Engineer certifies that all

requirements have been met.

SECTION 13.04 - PROHIBITED ACTIVITY

No person shall place landscaping in such a manner as to interfere with the

construction, maintenance and/or repair of any County road, ditch or right-of-

way. In the event that any such facility interferes in any manner with the

construction, maintenance and/or repair of any County road, the person,

company, or other entity in control of the landscaping shall alter it no later than

thirty (30) days after notice from the County Engineer and bear the cost and

expense of any change or alteration.

No person shall place landscaping in such a manner as to interfere with the use

of or obstruct vehicular or pedestrian traffic on any County road or drainage on

or along such road. No landscaping higher than thirty (30) inches shall be

placed in the visibility triangle.

No person shall place landscaping in such a manner as to constitute a danger

or hazard of any kind to persons or vehicles using or maintaining such road, or

any public property located within the boundaries of the County right-of-way.

The operation of construction equipment on the traveled surface of any

improved County road is prohibited unless the placement of landscaping cannot

be accomplished by any other method. In such instances, the equipment shall

use rubber tires on said traveled surfaces unless other methods are approved.

SECTION 13.05 - TREESCAPE AND SCREENING REQUIREMENTS FOR

COMMERCIAL ESTABLISHMENTS AND PUBLIC

BUILDINGS

The following requirements apply to all commercial and public buildings

constructed or substantially redeveloped after the effective date of these

regulations.

“Public Buildings and Commercial Establishments” include any building where

the public may gather or where goods or services are provided for

compensation. This definition includes, but is not limited to, auditoriums,

classrooms, churches, libraries, restaurants, theaters, schools, daycare

facilities, nursing homes, hospitals, correctional facilities, hotels, motels,

dormitories, department stores, shopping centers, doctor offices, general

offices, laundries, apartment complexes and warehouses. Not included in this

definition is an industrial facility having a fire brigade that conforms to

requirements of the Occupational Safety and Health Administration or

apartment buildings.

Public Buildings and Commercial Establishments (PB&CE) Requirements:

Each PB&CE fronting a public road shall be required to plant trees and shrubs

in accordance with the schedule listed below. A landscape design and

compliance review sheet as promulgated by the County Engineer shall be

submitted for review with each site plan for a proposed PB&CE. Nothing in

these regulations shall be construed as restricting such authority as the County

may have to remove or require the removal of any landscaping within the right-

of-way, whether or not constructed or maintained in conformance with these

regulations.

Street Trees:

The required number of street trees is derived by dividing by thirty (30) the

total length of all public street frontage measured in feet. Street trees are

required adjacent to all public streets, and the required number of street trees

must be planted along said frontage on private property and within ten (10)

feet of the property line. Exceptions may be granted in instances where trees

would encroach into a visibility triangle. Said trees shall be a minimum of 1.5

caliper inches in size and from the approved list found in Appendix “A” of

Chapter 33 of the City of Houston Code of Ordinances in effect at the time of

adoption of these regulations. If the development is part of a larger planned

development, then its pro rata share of street trees shall be provided. Street

trees shall be located on private property within ten feet of the adjacent

property line fronting the public right-of-way. This planting area can be

increased in cases where encroachment into a visibility triangle would create a

safety hazard. The required trees may be placed in the adjacent County right-

of-way to fulfill this requirement provided the following conditions are

satisfied:

1. Such planting is approved by the respective County Commissioner’s

designee.

2. Restrictive covenants exist to provide for the maintenance of said trees with

no County involvement.

3. Trees are planted in such a manner that they do not create a traffic hazard

or a potential to damage the sidewalk or street pavement.

4. Trees planted beneath a utility line shall not have a mature height of greater

than 25 feet.

Parking Lot Trees:

To calculate the number of required parking lot trees: determine the number of

parking spaces: divide by 10; and round up or down, unless less than one. A

minimum of one tree shall be provided. Said trees shall be a minimum of 1.5

caliper inches in size and located within 120 feet of each parking space. These

trees shall be from the approved list found in Appendix “A” of Chapter 33 of the

City of Houston Code of Ordinances in effect at the time of adoption of the these

regulations.

Parking Lot Shrubs:

Each development fronting a public street shall have a shrub barrier planted

along the perimeter of the parking lot to screen the parking area from the public

street. The shrubs shall be a minimum of 18 inches in height and shall be

selected from the City of Houston’s approved shrub list found in Appendix “D”

of Chapter 33 of the City of Houston Code of Ordinance in effect at the time of

adoption of these regulations. The number of shrubs required is equal to ten

times the number of street trees. No less than 75% of the shrubs required

under this section shall be planted along the perimeter of the parking lot

adjacent to the public street.

Buffer Requirement:

Any new commercial or public building proposed adjacent to existing single

family residential property shall provide a landscape buffer. An amenity

feature constructed within the subdivision is exempt from this requirement.

Acceptable buffers include:

a. A minimum of a six (6)-foot tall wood or masonry fence.

b. Evergreen plants capable of forming a year round screen of at least

six feet in height within three years of installation.

The buffer shall extend the entire distance between the existing single-family

residential development and the proposed public building or commercial

establishment or its pro rata share if it is a part of a larger development.

Pathways may be allowed through the buffer on a case-by-case basis.

SECTION 13.06 - TREE PLANTING REQUIREMENTS FOR SINGLE

FAMILY RESIDENTIAL LOTS

The following requirements apply to all single-family lots platted and recorded

after the effective date of these regulations. Nothing in these regulations shall

be construed as restricting such authority as the County may have to remove or

require the removal of any landscaping or plantings within the right-of-way,

whether or not constructed or maintained in conformance with these

regulations. Every lot greater than 5,000 sf in size shall require that a

minimum of two 1.5 inch minimum caliper trees are planted in the front yard.

Every lot smaller or equal to 5,000 sf in size shall require a minimum of one

1.5 caliper tree be planted in the front yard. These trees shall be planted prior

to occupancy of the residence. The trees must be selected from the City of

Houston’s approved tree list found in Appendix “A” of Chapter 33 of the City of

Houston Code of Ordinances in effect at the time of the adoption of these

regulations. These requirements shall appear on the face of the plat and in the

restrictive covenants of the subdivision. The required trees may be placed in

the County right-of-way to fulfill this requirement provided the following

conditions are satisfied.

1. Such planting is approved by the respective County Commissioner’s

designee.

2. The restrictive covenants are structured to provide for the

maintenance of said trees with no County involvement.

3. The trees are planted in such a manner that they do not create a

traffic hazard or a potential to damage the sidewalk or street

pavement.

SECTION 13.07 – PRESERVATION OF EXISTING TREES

Existing trees that are preserved and meet all these requirements may be

counted towards part or the entire tree requirement on a caliper inch basis for

any trees required by these regulations.

SECTION 14 – VARIANCES

If any person wishes an exception to any provision of these Regulations, such

person shall request a variance in writing from the Harris County Engineering

Department setting forth the provision(s) from which the variance is sought

and why the requested variance is needed. Such person must also explain how

equivalent measures to the provision(s) from which a variance is sought will

be provided or why the requirement(s) in the regulations is not applicable to

such person’s project. The Harris County Engineer shall hold a hearing, and

deny or grant the variance. The Harris County Engineer may approve a request

for variance to these Regulations based on sound engineering practice.

Variances will be granted only if the conditions of Section 60.6 of the Title 44

of C.F.R. are met. Specifically:

(a) The applicant has shown good and sufficient cause.

(b) It has been determined that failure to grant the variance would result in

an exceptional hardship to the applicant.

additional threats to public safety, extraordinary public expense, or

create nuisances, cause fraud or victimization of the public.

(d) Variances shall only be issued upon a determination that a variance is the

minimum necessary considering the flood hazard to afford relief.

Economic hardship shall not constitute the sole basis for granting a variance.

If a variance is granted, the person requesting such variance shall conform to

all applicable provisions of these Regulations except the Sections for which a

variance is granted.

SECTION 15 – VESTED RIGHTS

Subject to Local Government Code § 245.004(9), the rights to which a permit

applicant is entitled shall accrue are as follows:

1. Projects with a completed or unexpired administratively complete

application for Preliminary Plat submitted (does not include General

Plans) to Harris County or a municipality on or before midnight of the

effective date of the most currently amended Regulations provided that

the project is not Substantially Modified, or

2. An administratively complete development permit application that is

submitted to the County Engineer on or before midnight of the effective

date of the most currently amended Regulations provided the project is

not Substantially Modified, or

3. An administratively complete submitted drainage report for a

development project to the County Engineer on or before midnight of

the effective date of the most currently amended Regulations, provided

the project is not Substantially Modified.

It is the responsibility of the permit applicant to demonstrate a project’s

entitlement to vested rights under this Section. If a permit applicant believes

they are entitled to a vested right, that determination is to be completed prior

to the filing of an administratively complete permit application, plat

application, or development plan application.

Dormant projects as defined under Texas Local Government Code Section

245.005 are subject to review under these Regulations.

If no progress has been made towards completion of a project, the project

will be deemed a Dormant Project and an expiration date of two years from

will be placed on the associated Permit. Progress includes any one of the

following:

1. an application for a final plat or plan is submitted to a regulatory

agency;

2. a good-faith attempt is made to file with a regulatory agency an

application for a permit necessary to begin or continue towards

completion of the project;

3. costs have been incurred for developing the project including, without

limitation, costs associated with roadway, utility, and other

infrastructure facilities designed to serve, in whole or in part, the

project (but exclusive of land acquisition) in the aggregate amount of

five percent of the most recent appraised market value of the real

property on which the project is located;

4. fiscal security is posted with a regulatory agency to ensure

performance of an obligation required by the regulatory agency; or

5. utility connection fees or impact fees for the project have been paid to

a regulatory agency.

Having a permit application, plat application, or development plan

application approved under Section 4.09 Vested Rights does not relieve an

applicant from the requirement to comply with Texas Water Code 11.086.

Harris County’s review under Section 4.09 Vested Rights is not intended to

impair or impact a property owner’s remedies at law or in equity.

SECTION 16 - VESTED RIGHTS DETERMINATION

Any applicant who believes that they have obtained a Vested Right shall submit

to the County Engineer prior to the submission of an Administratively Complete

permit application, plat application or development plan application, a petition

explaining the factual and legal bases upon which the person relies to support

the contention that they have a particular vested right and consequently, is

exempt or not subject to a particular provision of these Regulations. The

petition shall include, at a minimum, the following:

1. The name, mailing address, phone number, and fax number of the

applicant (or the applicant’s duly authorized agent);

2. Identification of the property for which the person claims a vested

right;

3. Identification of the applications for which the applicant seeks relief

under this Section;

4. Identification of the “project” as that term is defined in Tex. Loc. Gov’t

Code § 245.001(3) and the permit application, permit, plat

application, plat, development plan application, drainage project, or

drainage report that gives rise to the project;

5. Identification of the original application for the first permit in the

series of permit required for the project, as described in Tex. Loc.

Gov’t Code § 245.001(1) and § 245.002(a) & (b) and each subsequent

permit application or permit constituting the series of permits, by type

of permit and dates filed or approved by the County Engineer;

6. Identification of all pertinent provisions of these Regulations in effect

at the time the original application for the permit, plat application or

development plan application was filed that (a) the applicant contends

control the approval, disapproval of the application for a permit, plat

application, or development plan for which relief is sought, pursuant

to Tex. Loc. Gov’t Code § 245.002(a) & (b);

7. Identification of all the specific provisions of these Regulations that

the applicant contends do not apply to the project due to Vested

Rights;

Within 15 days of receipt of a petition, the County Engineer shall make a

determination as to whether the petition contains the information required

above. If the County Engineer determines that the petition is not complete, he

must notify the applicant in writing within 5 days of the determination and

note the deficiencies. Within 30 days of the receipt of a petition that meets the

minimum requirements above, the County Engineer shall render a

determination that grants the relief requested in the petition, in whole or in

part, or denies the requested relief, in whole or in part. Prior to rendering the

determination, the County Engineer may request a pre-determination meeting

with the applicant to discuss the person’s Vested Rights claim and may request

additional documents or information related to the Vested Rights petition.

If the applicant believes the County Engineer determination is made in error,

the applicant may file an appeal with the Hearing Examiner under the

provisions of Sections ____. The appeal must be filed within 30 days of the

County Engineer’s determination.

SECTION 17 – VESTED RIGHTS APPEALS

The term “appellant” is used to refer to the appealing party.

(a) Vested Rights Appeals are initiated by the filing of an appeal with

the Hearing Examiner in writing.

(b) The Hearing Examiner (Examiner) will set a time for a hearing,

which will be scheduled as soon as practicable but within 15 days

of the receipt of the written appeal, and shall prepare a Notice of

Hearing naming the time and date of the Hearing. Copies shall be

distributed as follows:

1. The original copy and the Certificate to Commissioners'

Court will be filed with the Clerk of Commissioners' Court

and the Clerk will prepare a file for the Hearing Notice.

2. The Examiner will set up his own working or hearing file, in

which he will keep one copy.

3. The Examiner will give one copy to the Appellant.

4. The Examiner will deliver one copy to the County Engineer.

The Hearing will be conducted as provided in Section 18

below.

SECTION 18 – VESTED RIGHTS HEARING BEFORE THE EXAMINER

At Vested Rights Hearings before the Examiner, the Examiner will hear the

testimony of the County Engineer and any witnesses called by the County

Engineer. The Examiner will hear the testimony of the appellant and any

witnesses called by the appellant. The Examiner will review all documents and

exhibits submitted to him by the parties. The Examiner will not be bound by

formal rules of evidence and will control the evidence, reserving to himself the

power to exclude testimony or exhibits he does not consider relevant. The

Hearing Examiner will maintain an accurate record of the evidence adduced at

the Hearing.

SECTION 19 - FILING OF EXAMINER'S DECISION ON VESTED RIGHTS

APPEALS

The Examiner will prepare a written decision within 3 working days of the

Vested Rights Appeal Hearing. A copy of the Examiner’s decision will be filed

with the Clerk of Commissioners' Court, the members of the Commissioners'

Court and with the County Engineer. The original will be sent to the appellant's

address shown on the application.

SECTION 20 - REVIEW OF VESTED RIGHTS APPEAL BY COMMISSIONERS'

COURT

If the County Engineer, or the appellant wishes to appeal the Examiner's

decision, a written objection must be filed with the Clerk of Commissioners'

Court within (10) days of the date the Examiner's decision on vested rights is

filed. The Clerk will notify the Hearing Examiner who will place the matter on

the Agenda of Commissioners' Court for review at the next meeting of

Commissioners' Court. If the objection is filed by the County Engineer, notice

that the matter is on the agenda will be sent to the appellant by mail at the

appellant's address shown on the permit or application. Commissioners' Court

will review the matter. The Commissioners' Court may either affirm or reverse

the decision of the Hearing Examiner on vested rights.

SECTION 21 - SEVERABILITY

The provisions of these Regulations are severable. If any word, phase, clause,

sentence, section, provision, or part of these Regulations should be invalid or

unconstitutional, it shall not affect the validity of the remaining portions and it

is hereby declared to be the intent of the Commissioners’ Court that these

Regulations would have been adopted as to the remaining portions, regardless

of the invalidity of any part.

Appendix A

(As amended by Commissioners’ Court Order)

CERTIFICATES REQUIRED ON PLATS OF PROPERTY LOCATED IN THE

UNINCORPORATED AREA OF HARRIS COUNTY NOT WITHIN A MUNICIPALITIY’S ETJ

Dedicatory language must include the following paragraphs:

FURTHER, Owners do hereby dedicate to the public a strip of land fifteen (15) feet

wide on each side of the center line of any and all bayous, creeks, gullies, ravines, draws,

sloughs or other natural drainage courses located in said plat, as easements for drainage

purposes, giving the City (name of city), Harris County, or any other governmental agency,

the right to enter upon said easement at any and all times for the purpose of construction

and maintenance of drainage facilities and structures.

FURTHER, Owners do hereby covenant and agree that all of the property within the

boundaries of this plat and adjacent to any drainage easement, ditch, gully, creek or natural

drainage way shall hereby be restricted to keep such drainage ways and easements clear of

fences, buildings, planting and other obstructions to the operations and maintenance of the

drainage facility and that such abutting property shall not be permitted to drain directly

into this easement except by means of an approved drainage structure.

FURTHER, Owners certify and covenant that they have complied with or will comply

with existing Harris County Road Law, Section 31-C as amended by Chapter 614, Acts of

1973, 63

Legislature and all other regulations heretofore on file with the Harris County

Engineer and adopted by the Commissioners’ Court of Harris County.

Additional certification on the plat must indicate the floodplain status of the buildable

areas on “residential lots” on the plat, referring to the applicable Flood Insurance Rate

Map panel and effective date.

A. Buildable Areas Outside the Floodplain:

“I, ___________________, a Registered Professional Licensed Surveyor in the

State of Texas, do hereby certify that the buildable areas for all residential lots

are outside [or, are proposed to be outside, based on engineering plans and

specifications submitted to the County Engineers Office,] the 100-Year

Floodplain as shown on Federal Insurance Rate Map Panel No. [insert panel

number] dated [insert effective date of map]. This certification is based solely

on plotting boundaries from the FIRM Map, and no technical analysis was

conducted.”

B. Buildable Areas in the Floodplain

“I, ____________________ a Registered Professional Licensed Surveyor in the

State of Texas, do hereby certify that the buildable areas for all or some of the

residential lots are located within the 100-year floodplain as plotted from the

Federal Insurance Rate Map Panel No. [insert panel number] dated [insert

effective date of map] and are subject to flooding. The 100-year floodplain is a

flood hazard area prone to flooding, and subject to additional floodplain

management regulations.”

Floodplain easement dedicatory language must be shown on the plat if a Floodplain

Easement is required in accordance with Section 4.07 Floodplain Easements.

”A Floodplain Easement is hereby established over that portion of the effective

100-year floodplain area as delineated from FIRM PANEL No. XXXX dated XXXX

within the boundary of this final plat, the limits of which impact the buildable

areas of residential lots, wholly or partially, and within such area is prone to

flooding. (*See attached sketch.) Construction of any type of residential housing

within a Floodplain Easement is subject to additional flood hazard area

regulations. A Floodplain Easement may be abandoned by Harris County

Commissioners Court if the buildable area of a residential lot is determined to

be outside the 100-year floodplain by submitting County Engineer’s Form 1226,

with the applicable documentation and fee, to the Office of the County Engineer.

Certificate for Harris County Engineer:

I, John R. Blount, County Engineer of Harris County, hereby certify that the plat of

this subdivision complies with all the existing rules and regulations of this office as adopted

by the Harris County Commissioners’ Court and that it complies or will comply with all

applicable provisions of the Harris County Road Law as amended and all other Court

adopted drainage requirements.

____________________________________

John R. Blount, P.E.

County Engineer

Appendix A

Harris County Clerk Certificate of Commissioners’ Court Approval:

I, [insert County Clerk name], County Clerk of Harris County and ex officio clerk of the

Harris County Commissioners’ Court, do hereby certify that the within instrument was approved at

a legally convened meeting of the Harris County Commissioners’ Court held on

_______________________, 20__ by an order entered into the minutes of the court.

____________________________________

[insert County Clerk name]

County Clerk

of Harris County, Texas

By: _________________________________

Deputy

Harris County Clerk Certificate of Filing:

I, [insert County Clerk name], County Clerk of Harris County, do hereby certify that the

within instrument with its certificate of authentication was filed for registration in my office on

________________________, 200___, at __________ o’clock __.M., and duly recorded on

__________________, 200___, at __________ o’clock __.M., and at Film Code No.

______________________________ of the Map Records of Harris County for said county.

Witness my hand and seal of office, at Houston, the day and date last above written.

____________________________________

[insert County Clerk name]

County Clerk

of Harris County, Texas

By: ________________________________

Deputy

Appendix B

NOTARY FORMATS

a. For a natural person acting in his or her own right.

STATE OF TEXAS

COUNTY OF HARRIS

This instrument was acknowledged before me on _______ (date) by ______________ (name

or names of persons acknowledging).

Signature of Notary

NOTARY PUBLIC in and for

The State of Texas

b. For a natural person as principal acting as attorney-in-fact:

STATE OF TEXAS

COUNTY OF HARRIS

This instrument was acknowledged before me on _______ (date) by ______________ (name

of the attorney-in-fact) as attorney-in-fact on behalf of (name of the principal for whom the

document is signed).

Signature of Notary

NOTARY PUBLIC in and for

The State of Texas

c. For a partnership acting by one or more partners:

This instrument was acknowledged before me on _______ (date) by ______________ (name

of the partner or partners signing), partner(s) on behalf of (name of the partnership).

Signature of Notary

NOTARY PUBLIC in and for

The State of Texas

Appendix B

d. For a corporation

This instrument was acknowledged before me on _______ (date) by ______________ (name

of officer), (title of officer) of (name of corporation), a (state in which incorporated)

corporation, on behalf of said corporation.

Signature of Notary

NOTARY PUBLIC in and for

The State of Texas

e. For a public officer, trustee, executor, administrator, guardian, or other representative.

This instrument was acknowledged before me on (date) by (name of the representative

signing), as (title of representative) of (name of the entity or persons represented).

Signature of Notary

NOTARY PUBLIC in and for

The State of Texas

Appendix C

CITY OF HOUSTON DESIGN MANUAL

Department of Public Works & Engineering Graphic Requirements

Chapter 3

GRAPHIC REQUIREMENTS

3.01 CHAPTER INCLUDES

A. Graphic requirements for engineering plans.

3.02 REFERENCES

A. City of Houston monument ties in compliance with Article IV, Chapter 33, City Surveys, of

the Code of Ordinances.

3.03 DEFINITIONS

A. Computer Aided Drafting Design (CADD) - Preparation of drawings, plans, prints, and other

related documents through the use of computer equipment and software programs.

3.04 DESIGN REQUIREMENTS

A. Provide a cover sheet for projects involving three or more design plans (excluding

standard City of Houston detail sheets). Plan sheet numbers and titles shall be listed on

the cover sheet. Include an area key map and vicinity map to identify project location.

B. For Design Contracts with the City coordinate with the designated City project manager for

sheet size.

C. Show service area on cover sheet or area map.

D. Final design plans shall be India ink on mylar, or produced by CADD on mylar using

non-water based ink. Do not use adhesive-backed material on final plans. Stick-ons may

be allowed with approval of the City Engineer for a minor correction during the final review

process.

E. Details of special structures (not covered by approved standard drawings, such as stream or

gully crossings, special manholes, or junction boxes) shall be drawn with vertical and

horizontal scales equal to each other.

F. Each set of engineering plans shall contain paving and utility key drawings indexing

specific plan and profile sheets. City Standard Details, where applicable, shall be included.

All sheets shall have standard title blocks. Where applicable, show HCFCD key drawings

and numbers.

G. Draw key overall layouts to a minimum scale of 1" = 200'.

H. Plan stationing must run from left to right, except for short streets or lines originating from a

major intersection, where the full length can be shown on one sheet.

I. A north arrow is required on all sheets and should be oriented either toward the top or to the

right. This requirement is waived under the following conditions:

1. A storm water or sanitary sewer with flow from west to east or from south to north.

2. A primary outfall drainage ditch with flow from west to east or from south to north.

3. Stationing is intended to start from the cardinal points of the compass and proceed in

the direction of construction.

J. Standard scales permitted for plans and profiles of paving and utility construction drawings

are as follows:

1. Major thoroughfares, streets with esplanades over 400 feet in length, or special

intersections/situations.

1" = 20' Horizontal, 1" = 2' Vertical

2. Minor or residential single-family streets.

1" = 20' Horizontal, 1" = 2' Vertical

1" = 50' Horizontal, 1" = 5' Vertical, or

1" = 40' Horizontal, 1" = 4' Vertical

3. Scales of Paragraph 3.04J.2 above are minimum; larger scales may be used to show

details of construction.

4. Deviation from specified scales can only be permitted with special approval of the City Engineer.

For Design Contracts with the City coordinate the required scales on minor streets with the

designated City project manager.

5. Single-banked plan-and-profile drawings are acceptable; double-banked plan-and-profile

sheets are allowed in certain situations such as off-site utility lines in

undeveloped areas.

K. Show ties on drawings to City monuments when applicable; otherwise, make a statement on

the cover sheet referencing assumed control coordinates.

L. Each sheet of the plan and profile shall have a benchmark elevation and description defined.

M. The seal, date, and original signature of the Professional Engineer responsible for the

plans is required on each sheet developed by the design engineer. The design engineer

may use stamped seal or embossed imprint; however, the embossed imprint must be shaded

so that it will reproduce on prints.

N. A copy of the final plat for new development shall be included with the final design plans

when submitted for final approval.

O. If a roadway exists where plans are being prepared to improve or construct new

pavement or a utility, label the existing roadway width, surfacing type, and thickness.

P. Show all street and road alignments on plans.

Q. Develop plans to accurate scale showing proposed pavement, typical cross sections,

details, lines and grades, and existing topography within street right-of-way, and any

easement contiguous with the right-of-way. At the intersection, the cross street details shall

be shown at sufficient distance (20-foot minimum distance outside the primary roadway

right-of-way) in each direction along cross street for designing adequate street crossings.

R. Match lines between plan and profile sheets shall not be placed or shown within cross street

intersections including cross street right-of-way.

S. Show natural ground profiles as follows:

1. For privately-funded projects, centerline profiles are satisfactory except where a

difference of 0.50 feet or more exists from one right-of-way or easement line to the

other, in which case, dual profiles are required.

2. For City projects, provide natural ground profiles for each right-of-way line.

Easement profiles shall conform to Paragraph 3.04T.1.

T. Basic plan and profile sheets shall contain the following information:

1. Identify lot lines, property lines, easements, rights-of-way, and HCFCD outfalls.

2. Label each plan sheet as to street/easement widths, pavement widths, pavement

thickness where applicable, type of roadway materials, curbs, intersection radii, curve

data, stationing, existing utilities (type and location), and any other pertinent feature

affecting design.

3. Show utility lines 4 inches in diameter or larger within the right-of-way or

construction easement in profile view. Show utility lines, regardless of size, in the

plan view, including communication and fiber optic cables.

4. Graphically show flow line elevations and direction of flow for existing ditches.

5. Label proposed top of curb grades except at railroad crossings. Centerline grades are

acceptable only for paving without curb and gutters.

6. Show in profile curb return elevations for turnouts.

7. Gutter elevations are required for vertical curves, where a railroad track is crossed.

8. For street reconstruction projects, show in profile the centerline elevation at the

property line of existing driveways.

9. Show both existing and proposed station median noses or the centerline of

median openings, including median width.

10. The design of both roadways is required on paving sections with a median.

11. Show in plan view station PCs, PTs, and radius returns. Show in profile station radius

returns and grade change PIs with their respective elevations.

12. All existing and proposed utilities and pavement shall be on the same plan and profile

sheet for a given section unless approved otherwise by Project Manager.

13. Plan view and profile view shall be on the same sheet whenever practical.

U. For plant work, use a grid system to locate proposed work.

3.05 GRAPHIC STANDARDS

A. The following graphic standards for plan and profile shall apply to plans of 1" = 20'

scale. For smaller scale plans, use proportionally smaller line sizes.

B. Existing Improvements: The standards shown in Figure 3.1, Existing Improvements, are

required for depicting existing improvements on base plans. Use lower case letters with a

No. 0 reprographic pen or equal line weight unless otherwise shown in the pen/line weight

table, Figure 3.3, Line Code Definitions. Smaller pen sizes for lettering may be used for

clarity.

C. Proposed Improvements: The standards shown in Figure 3.2, Proposed Improvements, are

required for depicting proposed improvements on base plans. Use upper case letters with

a No. 3 reprographic pen or equal line weight unless shown otherwise in the pen/line weight

table, Figure 3.3, Line Code Definitions. Smaller pen sizes for lettering may be used for

clarity.

D. Signature Block: Use latest edition of Signature Blocks issued by the Engineering and

Construction Division for private and City projects.

END OF CHAPTER

Appendix D

CONSTRUCTION NOTES TO BE

ON ALL PROJECTS

DESCRIPTION OF ITEM

1 Water lines, wastewater collection systems, and storm drainage systems shall be

designed and constructed in accordance with the CITY OF HOUSTON’S, DEPARTMENT

OF PUBLIC WORKS AND ENGINEERING “DESIGN MANUAL, STANDARD

CONSTRUCTION SPECIFICATIONS, AND DETAILS FOR WASTEWATER COLLECTION

SYSTEMS, WATER LINES, STORM DRAINAGE AND STREET PAVING”.

2 All storm sewer will be reinforced concrete (C76 Class III) and shall be installed,

bedded and backfilled in accordance with the City of Houston’s Drawings 02317-02,

02317-03, 02317-05, 02317-06 and 02317-07 as applicable.

3 All storm sewers constructed in side lot easements shall be R.C.P., minimum twenty

(20) foot wide easements shall be provided.

4 An alternative to cement stabilized sand may be used as backfill for pipes fifty-four

(54) inch and larger, from 1-foot above the top of the pipe to the bottom of the

subgrade. Contractor may backfill with suitable material, provided the backfill

material is placed in eight (8) inch lifts and mechanically compacted to ninety-five

(95)% standard proctor density. Tests shall be taken at one hundred (100) foot

intervals on each lift. Bedding and backfill to one (1) foot above the top of the pipe

shall be cement-stabilized sand.

5 All proposed pipe stub-outs from manholes or inlets are to be plugged with eight (8)

inch brick walls unless otherwise noted.

6 The contractor(s) shall notify Harris County Engineering Department – Permit Office

twenty-four (24) hours in advance of commencing utility and/or paving construction

at (713) 274-3823 and written notification forty-eight (48) hours in advance of

commencing construction at 10555 Northwest Freeway, Suite 144, Houston, TX 77092.

7 Paving shall be in accordance with the “Regulations of Harris County, Texas for the

Approval and Acceptance of Infrastructure” and/or amendments of the same.

8 Guidelines set forth in the latest edition of the “Texas Manual on Uniform Traffic

Control Devices, TMUCD with Revisions” shall be observed.

9 OWNER OR OWNER’S AGENT to obtain all permits required by the “Regulations of

Harris County, Texas for Floodplain Management” prior to starting construction.

10 OWNER OR OWNER’S AGENT to obtain all notifications required by Harris County,

Texas prior to starting construction of utilities and/or culverts within Harris County

and Harris County Flood Control District Rights-of-Way.

PLEASE ADD ALL NOTES CIRCLED IN RED TO THE CONSTRUCTION PLANS.

Appendix E

CONSTRUCTION NOTES INVOLVING UTILITIES AND PAVING WORK

LOCATED WITHIN A PUBLIC RIGHT-OF-WAY

DESCRIPTION OF ITEM

NOTE: “Notifications Issued by Harris County Engineering

Department – Permits Office – is required for proposed work within

Harris County Right-of-Way. The project must be approved prior to

obtaining the required Notification. Be advised that a Notification

must be obtained separately from site development permit package.

For additional information, please visit

http://www.eng.hctx.net/permits/Public-Review-Code/Public-Plan-

Review/Notification-of-Construction-in-the-ROW or contact Public

Review Inspections Department @ (713-274-3931)”

Appendix F

CONSTRUCTION NOTES FOR

ESPLANADE OPENINGS AND TURN LANES

DESCRIPTION OF ITEM

1 Esplanade noses at the crossover are to be bullet type, painted reflectorized yellow,

in accordance with the Harris County Pavement Marking Detail and to be six inches

(6”) thick with surface colored black for concrete pavement and uncolored for asphalt

pavement, a minimum of six feet (6’) deep measured from the end of the median nose

and the curbs are at least four feet (4’) in width face to face.

2 The relocation of existing trees, landscaping, sprinkler systems, water meters, fire

hydrants, manholes, and pipelines (if applicable) are to be re-installed as

recommended by the Harris County Engineering Department – Permit Office and/or

the Harris County Precinct (If located in Precinct 3, add note: Contractor(s) to

contact Precinct 3 Parks Administration Office @ (281-531-1592) two (2) weeks

prior to construction for tree(s) and landscaping relocation.

3 Existing reinforced concrete pavement is to be machine saw-cut 1-1/2 inches deep to

expose a minimum of twenty-four (24) inches of reinforcing bars and place new

reinforcing bars to match existing steel size and spacing and tie new reinforcing bars

to existing reinforcing bars with eighteen (18) inch laps. Full depth saw-cut may be

used as an alternative.

4 Reinforcing concrete pavement is to be a minimum eight (8) inches with a minimum

of 5.0 sack cement per cubic yard, [4500 psi in twenty-eight (28) days]. Note: Depth

of concrete to meet current requirements of depth of existing pavement whenever it

is greater.

5 Asphalt turn lane to be minimum (2) inches H.M.A.C. with (10) inch base. Road

widening’s done on asphalt roadways for turn lanes must be overlaid full width of the

roadway from beginning to ending transition.

6 Subgrade shall be a minimum of six (6) inches for asphalt and eight (8) inches for

concrete, of a material as specified by the engineer and approved by Harris County,

and compacted to ninety-five (95) percent standard proctor density (+/-) two (2)

percent moisture. Cement stabilized sand, as prescribed by Harris County specs, may

be used as an alternative.

7 Slope on proposed concrete left turn slots is to be a minimum of 1/8 inch per foot with

crown at center of esplanade.

8 All sewers under or within one (1) foot of proposed or future pavement shall be

backfilled with 1-1/2 sack cement stabilized sand to within one (1) foot of subgrade.

9 The contractor shall notify the Harris County Engineering Department – Permit Office

twenty-four (24) hours in advance of commencing construction at (713) 274-3931 and

written notification forty-eight (48) hours in advance of commencing construction for

commercial and residential development.

Appendix F

CONSTRUCTION NOTES FOR

ESPLANADE OPENINGS AND TURN LANES

DESCRIPTION OF ITEM

10 All pavement work will require an accredited lab certification for subgrade, concrete

compressive strength, in place core. Asphalt work will require a sieve test, subgrade

and base compaction results.

11 Paving shall be in accordance with the “Regulations of Harris County, Texas for the

Approval and Acceptance of Infrastructure” relating to the approval and acceptance

of improvements in subdivisions or re-subdivisions and/or amendments of the same.

12 Guidelines set for in the “Manual on Uniform Traffic Control Devices” shall be

observed.

13 Include Harris County Drawing SD-1 as part of the construction plans.

14 Include Harris County Pavement Marking Detail as a part of the construction plans.

15 NOTE: “Notification(s) issued by Harris County Engineering Department - Permit

Office required prior to construction of utilities or turn lanes within Harris County

rights-of-way”. Contact Harris County Permit Office at (713) 274-3931.

16 OWNER OR OWNER’S AGENT to obtain all permits and notification(s) required by

Harris County, Texas prior to starting construction of utilities and/or culverts within

Harris County road rights-of-way.

PLEASE ADD ALL NOTES CIRCLED IN RED TO THE CONSTRUCTION PLANS.

Appendix G

CONSTRUCTION NOTES FOR ALL

PROJECTS LOCATED IN THE 1% (100-YEAR) FLOODPLAIN AND .2%

(500-YEAR) FLOODPLAIN

DESCRIPTION OF ITEM

1 All proposed construction shall be in accordance with the “Regulations of Harris

County, Texas for Floodplain Management”.

2 OWNER OR OWNER’S AGENT to obtain all permits required by Harris County,

Texas prior to starting development within Harris County and Harris County road

rights-of-way.

Appendix H

Intensity Duration Curves

Region 3*

*Regions can be found in the Harris County Flood Control District Policy, Criteria, and Procedure Manual Reference Section

6.02.1.B. for design requirements.

Intensity,

Coefficient

50 % AEP 20 % AEP 10 % AEP 4 % AEP 2 % AEP 1 % AEP 0.2 % AEP

2-Year 5-Year 10-Year 25-Year 50-Year 100-Year 500-Year

Region 3

e 0.7244 0.6900 0.6623 0.6294 0.6096 0.5797 0.5196

b (in.) 48.35 52.32 54.68 57.79 61.00 60.66 62.17

d (min.) 9.07 7.88 6.96 5.89 5.46 4.44 2.95

AEP - annual exceedance probability

)( TCd



1.0

10.0

10 100

Rainfall Intensity (in/hr)

Time of Concentration, TC (min)

2 Year

5 Year

10 Year

25 Year

50 Year

100 Year

500 Year

Appendix I

Button Detail For: Knuckle Configuration

Appendix J

Benchmark Requirements

Standards

New benchmarks are required to use the same criteria established during the Tropical

Storm Allison Recovery Project. The mark will be established using NAVD 1988, 2001

Adjustment Elevation and the GEOID 99 ellipsoid model to match the current Flood

Insurance Rate Map effective June 18, 2007.

Use as much as possible dual frequency, full-wavelength Global Positioning System (GPS)

receivers. The National Geodetic Survey (NGS) 2-centimeter standard, as published in

NOAA Technical Memorandum NOS NGS-58 dated November 1997 is the vertical

surveying standard. The horizontal standard is the NGS Second Order Class I standard as

published in the Federal Geodetic Control Committee (FGCC) document entitled

“Geometric Geodetic Accuracy Standards and Specifications for Using GPS Relative

Positioning Techniques” dated August 1, 1989. In areas where it is impossible to use GPS

due to conditions such as obstructed sky visibility, precise differential leveling is required

to connect such obstructed benchmarks to the rest of the network. Differential leveling

will be used to meet the maximum loop misclosure specifications for the NGS Second

Order Class II vertical stand for leveling, as published in the FGCC document entitled

“Standards and Specifications for Geodetic Control Networks” dated September 1984.

The control will meet the NGS Classification system for Range VI positions. Range VI

indicates that these positions meet the 0.02 meter 0 0.05 meter Accuracy Standard for

Horizontal Position, Ellipsoidal Height, and Orthometric Height (elevation) and the 95%

confidence level.

Survey Control

The controls to be used are the Continuously Operating Reference Stations (CORS)

monitored by NGS. The CORS stations located at extensometer sites are constructed so

as to be unaffected by the subsidence of the ground around them. They are considered

by HGCSD and others to be the most stable control monuments in Harris County. The

three CORS sites are as follows:

PID AJ6426 ADDICKS 1795 CORS ARP (ADKS)

PID AJ6430 NORTHEAST 2250 CORS ARP (NETP)

PID AF9521 LAKE HOUSTON CORS ARP (LKHU)

PID = Permanent Identifier

ARP = Antenna Reference Point (physical bottom of the antenna)

The 1997.00 Epoch Date will be referenced to coincide with the existing network.

Benchmark Construction

A brass disk, provided by Harris County Flood Control District, shall be set in a drilled

hole in the concrete on a permanent structure and fastened with epoxy cement or

established as a permanent monument. A Reference Mark Number will be assigned to

your new monument. Stamp the new disk with the newly assigned Reference Mark

Number.

Benchmark Acceptance

Reference Mark submittal forms can be obtained from the Harris County Permits Office

or downloaded from the website, http://www.eng.hctx.net/permits. A Texas State

Registered Professional Land Surveyor is required to set, level and submit for

acceptance new benchmarks. Submit two (2) paper copies and the digital file of the

fully completed forms to the Harris County Permits Office. After acceptance, the

benchmark information will be uploaded to the Harris County benchmark website for

public use.

APPENDIX K

UNIFORM STANDARDS FOR PUBLIC STREET NAMING

This appendix is written to provide clarification to the street naming standards in

Harris County. Uniformity in street name selection is essential to public safety as it

reduces confusion to the general traveling public, and most importantly reduces

confusion to the emergency service providers.

PRINCIPLES:

Public street naming shall follow these principles:

1. Named in a manner that reduces confusion to the traveler, utility providers,

addressing authority, and most importantly the emergency service provider.

2. When located within, or partially within a Municipality or its Extraterritorial

Jurisdiction (ETJ), street name selection shall follow the guidelines for naming

streets enacted by that Municipality.

3. “One Street – One Name Principle” - Maintains the same name for the entire

limits of the street.

a. When presented the opportunity through a street limit extension or other

improvements, the County Engineer will, when able, require street name

uniformity for the entire limits of the street where it does not currently

exist.

b. Regardless of planned improvements, if at any point a safety concern is

discovered due to non-uniformity, the County Engineer may recommend

changing the street name to facilitate uniformity and safety.

4. All steps necessary to change a street name will be executed by the applicant.

GUIDELINES:

In general, to meet the three principles outlined above, the following are guidelines for

naming streets within Harris County:

1. A new street that is an extension of an existing street or master planned street

shall have the same name as the existing street.

2. A non-public street that is a direct extension of a public street or a cul-de-sac

shall not have the same name as the public street.

3. A directional prefix or suffix may be used to clarify the general location of a

street, provided that the use of the directional prefix or suffix is consistent with

the established naming convention within the area in which the street exists.

4. Street name suffixes shall be limited to the following uses:

a. “Circle”, “Court” and “Loop” shall be used only to designate streets that

terminate at a cul-de-sac or are configured as a geometrically looped street.

b. “Boulevard”, “Crossing”, “Crossroad, “Expressway”, “Motorway”,

“Parkway”, “Speedway” or “Throughway” shall be used only to designate

major thoroughfares, major collector streets, collector streets or other

streets designed to handle traffic volumes in excess of normal neighborhood

traffic generation or that are boulevard sections (i.e. median divided) with

at least two lanes of traffic in each direction.

c. “Bypass”, “Expressway”, “Freeway” and “Highway” shall be used only to

designate highway or freeways subject to jurisdiction of the state

department of transportation.

d. “Avenue”, “Drive”, “Road”, and “Street” shall be used only to designate

major thoroughfares, major collector streets, collector streets, or local

streets.

e. “Bridge”, “Fork”, “Lane”, “Oval”, “Passage”, “Path”, “Place”, “Trail” and

“Way” shall be used only to designate collector streets or local streets.

f. “Tunnel” shall be used only to designate streets that provide underground

or underwater passage.

g. A street name suffix shall not be used as part of the street name.

h. The abbreviation of a street name suffix shall be consistent with the United

States Postal Service postal addressing standards.

5. A street name shall not include any typographic characters or symbols.

6. An alphabetical or numerical street name shall not be used to name a new street

unless the new street is a direct extension of an existing street with an

alphabetical or numerical name that is not duplicative of an existing street name.

7. When a street changes horizontal direction by approximately 90 degrees, the

street name shall change.

For purposes of the section, the terms cul-de-sac, collector street, and local street shall

have the meanings assigned to those terms by the Federal Highway Administration

(FHWA) and/or American Association of State Highway and Transportation Officials

(AASHTO) “A Policy on Geometric Design of Highway and Streets”.

EXEMPTIONS

For streets located in an Extraterritorial Jurisdiction of a municipality, the County

Engineer will review requests for exceptions only after written approval for the

exception from the Municipality is obtained by the applicant. In locations without

Extraterritorial Jurisdiction, requests for exceptions will follow the procedures outlined

within the Harris County Infrastructure Regulations.