Ord. 0817 09-08-97ORDINANCE NO. 817
AN ORDINANCE OF THE CITY COUNCIL OF THE CITY OF PEARLAND,
TEXAS, REQUIRING MITIGATION OF INCREASED RUNOFF CAUSED BY
DEVELOPMENT, PROVIDING FOR REGIONAL DETENTION AS AN
ALTERNATIVE, TO ALLEVIATE THE NECESSITY FOR LOCAL DETEN-
TION, PROTECT PEARLAND CITIZENS FROM FLOOD HAZARDS
CREATED BY DEVELOPMENT; PROVIDING FOR STATUTORY
AUTHORIZATION AND METHODS OF REDUCING FLOOD LOSSES;
CONTAINING DEFINITIONS; PROVIDING A PENALTY FOR VIOLATION;
CONTAINING A SAVINGS CLAUSE, A SEVERABILITY CLAUSE AND A
REPEALER CLAUSE; PROVIDING FOR PUBLICATION, CODIFICATION,
AND AN EFFECTIVE DATE; AND CONTAINING OTHER PROVISIONS
RELATING TO THE SUBJECT.
WHEREAS, the City of Pearland, a home -rule municipality, is authorized by
Charter to adopt and implement necessary and reasonable ordinances in the best
interests of its citizenry; and
WHEREAS, the City of Pearland may, in accordance with its inherent police
powers take necessary actions to control drainage erosion of the City's topography
to prevent flood damage; and
WHEREAS, the City is authorized by Section 16.311 of the Water Code
(Flood Control and Insurance Act) to take all necessary and reasonable actions to
facilitate compliance with the requirements and criteria of the National Flood Insurance
Program; and
WHEREAS, health and safety issues associated with the increased runoff
caused by development in the City is steadily increasing; and
WHEREAS, continued development in the City is recognized as valuable and
desirable, although potentially threatening to itself, existing development, and to the
special flood hazard zones; and
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WHEREAS, the City recognizes the immediate need to mitigate the increased
runoff effects of development in the City; and
WHEREAS, the City has purchased tracts of land on which to build large
detention basin volume which this Council wishes to make available as an alternative
to mitigate the effects of existing and future development; now, therefore,
BE IT ORDAINED BY THE CITY COUNCIL OF THE CITY OF PEARLAND, TEXAS:
"ARTICLE 1
FINDINGS OF FACT, PURPOSE, AND METHODS
SECTION 1-A. FINDINGS OF FACT
(1) Construction practices of earth -filling and earth -excavating on lots and land
tracts to elevate the land above local flooding threats, or to divert existing runoff
patterns, often disrupt the natural or existing historical drainage patterns onto and off
of neighboring lots or land tracts.
(2) All development within the City affects the special flood hazard areas,
because all lands in the City drain to streams that flow through special flood hazard
areas as defined by National Flood Insurance maps for the community of Pearland.
(3) Mitigation of increased runoff for all development in the City is necessary
and critical in order to protect the health, safety, and welfare of the citizenry generally
and to further FEMA objectives.
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SECTION 1-B. STATEMENT OF PURPOSE
The City of Pearland has a substantial governmental interest in requiring and enforcing
mitigation regulations. These regulations will benefit all property owners in the City
and will be applied proportionately in accordance with scientific methodology. It is the
purpose of this Ordinance to promote the public health, safety and general welfare by
implementing provisions designed to:
(1) Minimize public and private costs associated with flooding in residential and
business areas by reducing flooding conditions in the City through more effective
methods of developed runoff mitigation;
(2) Provide protection to Pearland citizens from certain uncontrolled actions of
others that may negatively impact the value of private property;
(3) Protect development inside and outside special flood hazard areas from the
cumulative effect of development in the City at large;
(4) Reduce the proliferation of small, local detention ponds;
(5) Help enhance an increasing, stable tax base by offering the option of
replacing small, local detention on valuable uplands with space in large regional
detention in lower value lowlands.
SECTION 1-C. METHODS OF MITIGATION, CUMULATIVE EFFECT MINIMIZATION,
AND CONTROLLING NEIGHBORING DIVERSIONS
In order to accomplish its purpose, this Ordinance uses the following methods:
(1) Require all development to mitigate the effects of increased runoff created
by said development; and
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(2) Require conditional development permit for all lot and land filling, and
excavation or runoff barrier construction;
(3) Commit regional detention space to initiate the alleviation of existing
flooding;
(4) Where applicable and available, offer regional detention space for
development projects as an alternative to small, local detention ponds.
ARTICLE 2
DEFINITIONS
ACRE-FOOT - the volume of space equivalent to 12 inches (one foot) of water on one
acre of land.
DETENTION FACILITIES - include but are not limited to basins, ponds, restricted -outlet
ditches, depressed grading and/or paving, pipes, channels, and flood plains, that cause
rainfall runoff to leave an area more slowly than it otherwise would.
DEVELOPMENT - all construction on land that creates new surface disturbances that
result from filling, excavating or surfacing activities on the land. For purposes of this
Ordinance, DEVELOPMENT does not include adding a floor to a building, building on
an existing slab, replacing an existing slab or pavement with a new slab or pavement
of same size at existing grades, or other activities that do not change the amount of
impervious cover on the land, or the grades of said land or surfaces.
DEVELOPMENT PERMIT - a formal document, approved by the City Engineer or his
designee, issued by the City of Pearland, permitting construction of the project applied
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for, including but not limited to a Building Permit, Development Permit, approved and
signed construction plans and specifications, or Developer Agreement.
EQUIVALENT IMPERVIOUS AREA - the area of impervious land equal in new runoff
potential to a mixture of pervious and impervious land that is larger in total area.
FLOOD OR FLOODING - a general and temporary condition of partial or complete
inundation of normally dry land area.
IMPERVIOUS AREAS - areas of land or other surfaces that intercept rainfall, preventing
it from being absorbed into that surface.
LOCAL DETENTION - a detention feature built within the property lines of a proposed
or existing development for the purpose of mitigating only the developed runoff from
that development.
MITIGATION - employment of physical or management means of limiting the impact
of development upon the existing surrounds; limiting the effects of increased runoff
due to development activities.
OFFICIAL BENCHMARK - any formally installed monument placed at a known elevation
above Mean Sea Level in reference to the National Geodetic Vertical Datum (NGVD)
of 1929 that is accepted by the City of Pearland.
PUBLIC DRAINAGE WAY - any channel, pipe, ditch, swale, street, paved way, creek,
or river which clearly lies within the public domain as a legal right of way, easement,
public fee title in agency having jurisdiction, or historically incontestable public
prescriptive right, and which bears no reasonable risk of individual private proscription.
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REGIONAL DETENTION - detention that is effective over an area of land that includes
more than one development project.
REPLACEMENT DETENTION - detention of developed runoff at a site other than the
site responsible for increasing runoff.
SPECIAL FLOOD HAZARD AREA - the land in the floodplain within a community
subject to a one percent chance of flooding in any given year, according to published
National Flood Rate Insurance Maps.
WATER SURFACE ELEVATION - means the height above Mean Sea Level, in relation
to the National Geodetic Vertical Datum (NGVD) of 1929 (or any other datum
specified), of floods of various magnitudes.
ARTICLE 3
ADMINISTRATION
SECTION 3-A. DESIGNATION OF ADMINISTRATOR
The City Engineer, or his designee, is hereby authorized to administer and implement
the provisions of this Ordinance and other appropriate regulations and standards
pertaining to flood hazard reduction in the City of Pearland.
SECTION 3-B. DUTIES AND RESPONSIBILITIES OF THE ADMINISTRATOR OR HIS
DESIGNEE
Duties and responsibilities of the Administrator or his designee shall include, but not
be limited to, the following:
(1) Establish within the intent and purposes of this Ordinance, the criteria,
standards, and procedures for administration and enforcement of drainage and flood
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mitigation for all development, including but not limited to the implementation of a
system for approving and issuing development permits.
SECTION 3-C. DEVELOPMENT PERMIT REQUIRED
A Development Permit is required for all development in accordance with this
Ordinance.
SECTION 3-D. PERMIT PROCEDURES
(1) Development Permits required by this ordinance for all development projects
within the City shall be reviewed only after Application is made on a form provided by
the Administrator or his designee including, but not limited to (1) a site plan prepared
by a registered engineer or surveyor depicting existing and proposed site
improvements, and (2) a drainage plan with elevations based upon official
benchmarks. The required drainage plan shall provide for delivery of the design event
runoff from the project property to a public drainage way easement or drainage or
street right of way, including provisions for acceptance, mitigation, and conveyance
of excess runoff created by the proposed development. Building Permits and signed,
approved formal engineered plans and specifications shall also qualify as
Development Permits.
a. Provisions must be made for constructing mitigation of rainfall runoff
rates in excess of historical runoff rates for all projects. In the absence
of other more applicable criteria, the 100-year storm event shall be used
for determining runoff rates and required mitigation.
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b. For those projects electing replacement detention mitigation by reserving
space in a regional detention basin, the Development Permit application
must include a detailed engineering report that demonstrates the runoff
mitigation equivalence of replacement detention in a regional detention
basin to local, or on -site mitigation. This report will form the basis for
negotiation that will result in a Development Agreement between the City
and the developer. Execution of the Development Agreement by the
developer and the City Manager or his designee will complete the
requirements for a Development Permit when rep/acement detention,
available in a regional detention basin, is elected. Existing small, local
detention ponds may be abandoned only if an acceptable plan for
replacement detention in a regional detention basin is submitted in
accordance with this ordinance, and a Development Agreement is
executed.
(2) Approval or denial of a Development Permit by the Administrator or his
designee will be based on the following factors:
a. Risk of flooding posed to existing development;
b. Access limitations to the proposed development in times of flooding,
including but not limited to requirements of the Emergency Management
Director;
c. Risk of flood damage to the proposed project;
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d. Cost of services to the proposed development during and after flooding;
e. Availability of alternatives to the proposed project;
f. Level of mitigation provided by the proposed development.
SECTION 3-E. VARIANCES
(1) The Building Board of Adjustment and Appeals as established by the.City
of Pearland shall hear and render judgement on requests for variances from the
requirements of this Ordinance when there is an alleged error in any requirement,
decision, or determination made by the Administrator in the enforcement or
administration of this Ordinance which contravenes the intent of the ordinance,
including but not limited to (a) unique site characteristics, (b) timing of proposed
development, or (c) conflicts with existing contracts.
ARTICLE 4
STANDARDS FOR PROJECT PROPOSALS TO AID FLOOD HAZARD REDUCTION
SECTION 4-A. STANDARDS
All project proposals under this Ordinance in the City of Pearland shall meet the
following standards:
(1) 1992 Clear Creek Regional Flood Control Plan and the 1989 Hydraulic
Baseline Report by Dannenbaum Engineering, Inc., as revised from time
to time;
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(2) Existing and approved local area drainage plans not superseded by (1)
above;
(3) Standard practices and published records and methodology known to
established and qualified practitioners of hydrology and hydraulics;
(4) Rules, regulations, and procedures issued by the Administrator
designated herein in accordance with the plans, studies, and
methodology listed above.
ARTICLE 5
GENERAL PROVISIONS
SECTION 5-A. LANDS TO WHICH THIS ORDINANCE APPLIES
This Ordinance shall apply to all areas of land within the incorporated limits of the City
of Pearland and the City's Extraterritorial Jurisdiction ("ETJ") in accordance with the
City's Subdivision Ordinance, and as allowed by law.
SECTION 5-B. WARNING AND DISCLAIMER OF LIABILITY
The flood protection practices required by this Ordinance are considered reasonable
for regulatory purposes and are based on scientific and engineering considerations.
Floods greater than design floods may occur, and flood depths may be increased by
man-made or natural causes. This Ordinance does not imply that all lands intended
to be protected will be free from floods or flood damages. This Ordinance shall not
create liability on the part of the City of Pearland or any official or employee hereof for
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any flood damages that result from reliance on this Ordinance or any administrative
decision lawfully made hereunder.
SECTION 5-C. INTERPRETATION
In the interpretation and application of this Ordinance, all provisions shall be:
(1) considered as minimum requirements; (2) liberally construed in favor of the
governing body; and (3) deemed neither to limit nor repeal any other powers granted
by the City's Charter, state, federal or other applicable law or regulation.
SECTION 5-D. COMPLIANCE
No structure or land shall hereafter be located, altered, or have its hydrologic or
hydraulic nature changed without full compliance with the terms of this Ordinance and
all other applicable regulations.
SECTION 5-E. VIOLATION AND PENALTY
(1) Any person, firm or corporation who shall violate any of the provisions of
this Ordinance or fail to comply therewith or who shall violate or fail to comply with
any order or regulations made thereunder, or who shall build in violation of any
detailed statement of specification of plans submitted and approved hereunder, or any
certificate or permit issued hereunder, shall, for each and every violation and
noncompliance respectively be deemed guilty of a misdemeanor, and upon conviction
thereof shall be fined in a sum not to exceed Two Thousand Dollars ($2,000.00) and
each and every day that such violation or noncompliance shall exist shall be deemed
a separate offense.
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(2) If any person, firm or corporation violates any of the provisions of this
Ordinance or fails to comply herewith, the City of Pearland, in addition to imposing the
criminal penalties provided herein, may additionally institute any appropriate civil or
criminal actions or proceedings allowed by law to prevent, restrain, correct, or abate
any illegal act, conduct, business, or use in or about any land within its jurisdiction.
SECTION 5-F. ENACTMENT
Savings. All rights and remedies which have accrued in favor of the City under
this Chapter and amendments thereto shall be and are preserved for the benefit of the
City.
Abrogation and Greater Restrictions. This Ordinance is not intended to repeal,
abrogate, or impair any existing ordinances, easements, covenants, or agreements.
However, where this Ordinance and another ordinance, easement, covenant, or
agreement conflicts or overlaps, the more stringent restrictions shall apply.
Severability. If any section, subsection, sentence, clause, phrase or portion of
this Ordinance is for any reason held invalid, unconstitutional or otherwise
unenforceable by any court of competent jurisdiction, such portion shall be deemed
a separate, distinct, and independent provision and such holding shall not affect the
validity of the remaining portions thereof.
Repealer. All ordinances and parts of ordinances in conflict herewith are hereby
repealed, but only to the extent of such conflict.
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Codification. It is the intent of the City Council of the City of Pearland, Texas,
that the provisions of this Ordinance shall be codified in the City's official Code of
Ordinances as provided hereinabove.
Publication/Effective Date. The City Secretary shall cause this Ordinance, or its
caption and penalty, to be published in the official newspaper of the City of Pearland,
upon passage of such Ordinance. The Ordinance shall then become effective ten (10)
days from and after its publication, or the publication of its caption and penalty, in the
official City newspaper."
PASSED and APPROVED on First Reading on this '5 day of
A.D., 1997.
TOM REID
MAYOR
ATTEST:
PASSED and APPROVED on Second and Final Reading this day of
, A.D., 1997.
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TOM REID
MAYOR
ORDINANCE NO. 817
ATTEST:
APPROVI€D AS TO FORM:
a‘i /14 d.ilatK
AIVIY/MOTES McCULLOUGH
CITY ATTORNEY
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