Ord 041-88 4/5/1988 ,
ORDINANCE NO. ila-0
AN ORDINANCE REGULATING THE RATE OF DISCHARGE
OF STORM WATER RUNOFF: SPECIFYING CRITERIA
FOR DETERMINING RUNOFF RATES: ESTABLISHING
DEVELOPMENT STANDARDS FOR THE CONSTRUCTION OF
RUNOFF CONTROL FACILITIES: AND SETTING FORTH
PROCEDURES FOR THE ADMINISTRATION THEREOF
BE IT ORDAINED BY THE CITY COUNCIL OF THE CITY OF WICHITA
FALLS, TEXAS THAT:
SECTION I. PURPOSE. It is the purpose of this ordinance to
establish maximum rates for the discharge of storm waters into
the various watercourses of the City for the purpose of promoting
the health, safety and general welfare of the population by
minimizing or eliminating dangers of flooding to life and
property.
It is further the intent of this ordinance that runoff
control devices be provided as areas of land are developed or
redeveloped for urban use. It is not the intent of this
ordinance to utilize areas for the sole purpose of storing or
detaining excess storm water, but to permit such areas to be used
for other compatible urban uses as well.
SECTION II. DEFINITIONS.
A. Storm Water Runoff. Water that results from
precipitation which is not absorbed by soil or plant material.
B. Natural Drainage. Water which flows by gravity in
channels formed by the surface topography of the earth prior to
changes made by the efforts of man.
C. Excess Storm Water. That portion of storm water runoff
which exceeds the transportation capacity of storm sewers or
natural drainage channels serving a specific watershed.
D. Excess Storm Water Passage. A channel formed in the
ground surface to carry storm water runoff through a specific
area.
E. Storm Water Release Rate. The rate at which storm water
runoff is released from dominant to servient land.
F. Storm Water Storage Area. An area designated to
temporarily accumulate excess storm water.
G. Tributary Watershed. The entire catchment area that
contributes storm water runoff to a given point.
H. Dry Bottom Storm Water Storage Area. A facility that is
designed to be normally dry and which accumulates excess storm
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water only during periods when the restricted storm water runoff
release rate is less than the storm water inflow rate.
I. Wet Bottom Storm Water Storage Area. A facility that
contains a body of water and which accumulates excess storm water
during periods when the restricted storm water runoff release
rate is less than the storm water inflow rate.
J. Control Structure. A facility constructed to regulate
the volume of storm water runoff that is conveyed during a
specific length of time.
K. Positive Gravity Outlet. A term used to describe the
drainage of an area in a manner that will ensure complete removal
of all surface water by means of natural gravity.
L. Safe Storm Water Drainage Capacity. The quantity of
storm water runoff that can be transported within a channel,
passage, conduit, tube, duct, or combination thereof in such a
manner that the elevation of the water does not rise sufficiently
above the level of the adjacent ground surface so as to cause
damage to structures or facilities located thereon.
M. Low Flow. The transport or flow of a normal or usual
volume of storm water as opposed to a high or peak volume which
would utilize overflow facilities.
N. City. The City of Wichita Falls, Texas.
O. Director of Public Works. The Director of Public Works
or his/her designate.
P. Gross Aggregate Area. The area of the development under
consideration plus the area of any contiguous land, owned or
controlled by the developing entity.
SECTION III. REGULATIONS. The Department of Public Works
of the City of Wichita Falls, Texas, shall develop and establish
written policies, procedures, criteria and regulations concerning
the inspection, determination and approval of the standards for
the construction and/or development of storm water management
structures.
Such rules and regulations shall be adopted by resolution by
the City Council.
SECTION IV. ADMINISTRATION.
A. Prior to the construction of any storm water control
structure or storm water detention facility on the construction
or development site, the developer shall obtain a building
permit. No such permit shall be issued until the following
documents have been submitted to the Director of Public Works and
approved:
1. Plans and proposed methods for the prevention and
control of soil erosion.
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2 . Plans, specifications and all calculations for the
control of storm water runoff as required by
this ordinance and any rules and regulations
promulgated by the Director.
B. No Building permits for habitable structures shall be
issued for any development or redevelopment not complying with
this ordinance.
C. Any decision of the Director shall be pursuant to
written specifications and regulations as adopted by the City
Council.
SECTION V. APPLICATION. This ordinance shall apply to any
residential development comprising a gross aggregate area of two
(2) acres or more or to any commercial, industrial,
institutional, governmental, utility or other development or
redevelopment comprising a gross aggregate area of one (1) acre
or more. The gross aggregate shall include undedicated streets
and other dedicated lands. This ordinance shall not apply to
existing streets.
SECTION VI. GENERAL REQUIREMENTS.
A. Storm Water Release Rate. The controlled release rate
of storm water runoff shall not exceed that of an
undeveloped storm water runoff rate of 0. 35. The release rate
shall be the average value computed with excess storm water
representing 50% of the available storage volume.
However, developed areas which exceed the storm water
release rate, on redevelopment shall provide retention only as to
increase in impervious cover.
Such release rate shall be computed as a direct ratio of the
area of the tributary watershed and shall not exceed 0.50 cubic
feet per second per acre drained.
Where a proposed development contains only a portion of a
watershed or portions of several watersheds, the release rate and
storage requirements shall be based upon the proportion of the
area being developed as compared to the entire watershed
tributary to the proposed storage area.
Where it can be demonstrated by the Developer that a higher
storm water release rate will not be contrary to the purpose and
intent of this ordinance and where such proposed release rate
will not adversely affect properties in the downstream portion of
the watershed, the Director may permit such release rate to be
used as deemed appropriate.
B. Excess Storm Water Passage.
1. An excess storm water passage shall be provided for
all storm water storage areas. Such passage shall
have capacity to convey through the proposed
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development the excess storm water from the
tributary watershed. The capacity of such excess
storm water passage shall be constructed in such
a manner as to transport the peak rate of runoff
from a 100 year return frequency storm assuming all
control structures are inoperative, all upstream
areas are fully developed in accordance with the
City's current land use plan.
2. No buildings or structures shall be constructed
within such passage, however, street, parking lots,
playgrounds, park areas, pedestrian walkways, utility
easements and other open space shall be considered
compatible uses. In the event such passageway is
reshaped or its capacity to transport excess storm
water otherwise restricted, the Director shall notify
the agency, party or parties causing said restriction
to remove the same, and set a reasonable time for its
removal. If said persons refuse to or are unable to
comply with said order, the Director shall cause said
restrictions removed at the expense of said persons.
3. Where a proposed development contains existing
natural drainage, appropriate land planning shall be
undertaken to preserve said natural drainage as part
of the excess storm water passage.
C. Determination of Storage Capacity. The volume of
required storm water storage shall be calculated on the basis of
the runoff from a 100 year return frequency storm. Such
calculation shall be made in accordance with modified rational
hydrograph method of analysis as discussed in "Urban Storm Water
Management Special Report No. 49 "as published by the American
Public Works Association", or other method approved by the
Director. The applicable storm water runoff release rate shall
be considered when calculating the required storm water storage
capacity.
D. Compensating Storage. In the event the orderly and
reasonable development of an area requires the storage of excess
storm water to be located elsewhere, compensating storage (the
storage of an equal volume of excess storm water) may be provided
at an alternative location provided, however, that the
feasibility and details of storm water control shall be approved
by the Director.
E. Easements. Easements which cover excess storm water
passages, storm water storage areas and other control structures
shall be granted to the City for the purpose of repair,
alteration or to insure their proper operation, however, the City
shall reserve the right not to accept such easement or any
portion thereof.
SECTION VII. DRY BOTTOM STORM WATER STORAGE AREAS.
A. Design Criteria.
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1. Primary and Secondary Uses. Dry bottom storm water
storage areas shall be designed to serve a secondary
purpose for recreation, open space, parking lot, or
similar type of use that will not be adversely
affected by occasional intermittent flooding.
2. Drain System. A drainage system shall be provided
to transport low flow storm water runoff through
storage areas. Such drainage systems shall have a
positive gravity outlet to a natural passage or
storm drain with adequate capacity as described in
Section VI, subsection B.
No outlets from a storm water storage area are to be
less than four (4) inches in diameter.
3. Storage Duration. The combination of storage of
excess storm water runoff from a 100 year return
frequency storm and the allowable release rate shall
not result in a storage duration in excess of forty-
eight (48) hours.
4. Grades. Where turf areas are used for the bottom of
dry bottom storage areas, the minimum grades for
such areas shall be one-half ( .5) percent (200 units
horizontal to 1 unit vertical) . Maximum side slopes
for turf shall be twenty-five (25) percent (4 units
horizontal to 1 unit vertical) . Storage area side
slopes shall follow the natural land contours in
order to minimize the amount of earth work necessary
to create the storage facility.
5. Erosion Control. Erosion control measures
consisting of mulch, hydro-seeding, nurse crops,
sod installation or other approved means shall be
utilized to control soil movement within and around
the storage basin.
Energy dissipating devices or stilling basins shall
be provided to ensure that downstream soil
erosion is alleviated and the regime of the
downstream drainage facility is not disturbed.
6. Control Structures. Control structures shall be
designed as simple as possible and shall not require
manual adjustments for normal operation. Control
structures shall be designed to maintain a
relatively uniform flow independent of storm
water storage volume. Inlet structures shall be
constructed in such a manner to prevent high
velocity flow (above 10 feet per second) ; to provide
for the interception of trash and debris and for
soil erosion control. Inlets shall be designed to
eliminate turbulent flow conditions during any
portion of the storm water storage cycle.
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Overflows for each storm water storage area shall be
provided in the event a storm in excess of the design
capacity occurs. Such overflows shall be constructed to
function without specific attention and shall become part of the
excess storm water passage.
SECTION VIII. WET BOTTOM STORM WATER STORAGE AREAS.
A. Design Criteria. Wet bottom storm water storage areas
shall be designed in accordance with the design criteria
governing the construction of dry bottom storm water storage
areas, except for drains as required by Section VII.A.2.
The following additional regulations shall apply:
1. Construction. Minimum normal water depth shall be
two (2) feet. If fish are to be used to keep the
pond clean, at least 1/4 of the pond area shall have
a minimum depth of five (5) feet.
Facilities shall be provided to lower the pond
elevation by gravity flow for cleaning purposes
and land/water interface maintenance. Protection
of the land/water interface shall be provided to
alleviate soil erosion due to wave action.
2 . Control Structures. Control structures for storm
water release shall operate at their maximum rate
with only minor increases in the water surface level.
3 . Stagnation Control. Measures shall be included in
the design to prevent pond stagnation. Such
measures may include fountain aeration or other
approved means to ensure aerobic pond conditions.
4. Determination of Storage Capacity. When calculating
the storage capacity of wet bottom storage areas,
only the volume available to store excess storm
water shall be considered. Permanent water storage
does not constitute control of excess storm water
runoff.
SECTION IX. MISCELLANEOUS STORM WATER STORAGE AREAS.
A. Paved Surfaces. Paved surfaces, including automobile
parking lots in proposed storm water storage areas shall have
minimum grades of one third ( . 3) percent (300 units horizontal
to one (1) unit vertical) and shall be limited to storage
depths of one and one-half (1-1/2) feet maximum. Pavement
base design and construction shall be accomplished in such a
manner as to prevent damage from flooding. Control structures
in paved areas shall be accessible for maintenance and
cleaning. The use of vortex control facilities at inlets to
ensure that the maximum allowable release rates are being
developed shall be required as necessary.
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Where parking areas are used to store storm water, the
areas of greatest depth shall be restricted to the more remote,
least used areas of the parking facility.
B. Rooftop Surfaces. Rooftop storage of excess storm water
shall be designed with permanent-type control inlets and parapet
walls to contain excess storm water. Adequate structural roof
design shall be provided to ensure that roof deflection does not
occur which could cause roof failure. Overflow areas shall be
provided to ensure that the weight of stored storm water will
never exceed the structural capacity of the roof.
C. Underground Storage. Underground storm water storage
facilities shall be designed for easy access to accommodate the
removal of accumulated sediment. Such facilities shall be
provided with positive gravity outlets.
SECTION X. CONTROL IN EXCESS OF REQUIREMENTS.
Provision of Control Exceeding Requirements. In the
event storm water runoff control can be provided in excess of the
requirements of this ordinance and the benefit of such additional
control would accrue to the City of Wichita Falls at large, the
City may provide public participation in the increased cost of
the control of storm water runoff in proportion to the additional
benefits received.
SECTION XI. REPEALER. All ordinances or arts of
ordinances in conflict with the provisions of this ordnance are
hereby repealed.
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PASSED AND APPROVED THIS J /v O 986.
M A Y O R
ATTEST:
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CITY LERK
7
Ad 25'6390
ORDINANCE NO.35-88
AN ORDINANCE CLOSING, VA-
CATING,AND ABANDONING A
TWENTY-FIVE Affidavit of Publication
TWENTY-FIVE FOOT WIDE ALLEY
IN BLOCK 7, I JALONIC AD-
DITION,WICHITA FALLS,TEXAS.
NO.
ORDINANCE EN WAIVING 36-88
SEC-1 THE STATE OF TEXAS
TION 22-1(a)9 OF THE CODE OF
ORDINANCE TO ALLOW THE I COUNTY OF WICHITA
POSTING OF ADVERTISING DE-
VICES AT SCOTLAND PARK FOR )THE
%. .MARCH CHI Tie VENT WII`LLL I
BE HELD ON APRIL'9 AND 10, ' On this 2 7th April
1988. day of
ORDINANCE NO.37-88
ORDINANCE CLOSING HEAR-' 1988
ING AND FINDING AND/OR STRUC-
CERTAIN 1
BUI LDINGS AND/O A.D. personally appeared before me, the undersigned authority
BUILDINGS
TURES TO BE DANGEROUS: I D a r i c e Ming
COMMANDING PROPERTY I bookkeeper
OWNERS TO REPAIR OR DE-
STRUCTURES IDWITHINNTHIRTY ' for the Times Publishing Company of Wichita Falls, publishers of the Wichita Falls
(30)DAYS OF THE DATE OF THIS
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ORDINANCE NO 39.88 Texas, and upon being duly sworn by me, on oath states that the attached
THE ZONING NORDINANCE ITOI
CLARIFY THE DEFINITION OF advertisement is a true and correct copy of advertising published
PRIVATE CLUB AND THE REGU-
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HOLDING PRIVATE CLUB REGIS-I
TRATION PERMITS UNDER THE' April 25 , 19 8 8
TEXAS ALCOHOLIC BEVERAGE
CODE AND REGULATING THEM,
IN A SIMILAR MANNER AS '
ESTABLISMENTS THAT HAVE MTh
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CIDENTAL SALES AND SERVICE
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ORDINANCE NO.27-88
AN ORDINANCE EXTENDING
I THE CITY LIMITS OF THE CITY OFAL)WICHITA FALLS,BY ANNEXING Subscribed and sworn to before me this the day and year first above written.
CERTAIN TRACT OF LAND ADJA- �j� I'
CENT. F THE TERRITORIAL r G7��Y/G✓�
LIMITS OF THE CITY OF WICHITA
FALLS,TEXAS,WHICH TRACT OF C)11,f
LAND AND SERVICE PLAN FOR .
SUCH TRACT OF LAND ARE DE- ''°' -3 5:,*:Z;2kwx,2h.
SCRIBED IN THIS ORIDINANCE. .,'
ORDINANCE NO 38-88 ,,- 1 % 1';Ufy "
AN ORDINANCE REZONING A :;;.-;,.
4.67 ACRE TRACT OF LAND OUT °" ="?'w%'£:
OF BLOCKS 3 $ 4, SAYLES IR-
RIGATION SUBDIVISION, •WICHITA FALLS, TEXAS, FROM '
MOBILE HOME RESIDENTIAL
ZONE TO RESIDENTIAL MIXED
USE ZONE.
ORDINANCE NO.40-88 •
ORDINANCE ADOPTING OPER-
ATING PROCEDURES FOR THE
. SOFTBALL COMPLEX. •
ORDINANCE NO.41-88.
AN ORDINANCE REGULATING
RATE OF DISCHARGE OF
STORM WATER RUNOFF:SPECI-
FYTHE ING CRITERIA FOR DE-
TERMINING RUNOFF RATES:ES-
TABLISHING DEVELOPMENT
STANDARDS FOR THE CON-
STRUCTION OF RUNOFF CON-
TROL FACILITIES:AND SETTING
FORTH PROCEDURES FOR THE
ADMINISTRATION THEREOF.
ORDINANCE NO.42-88
ORDINANCE APPROVING SOL-
ICITATION OF PROPOSALS FOR
A FEASIBILITY ASSESSMENT FOR
• THE PROJECT AND FINANCE
PLANS FOR REINVESETMENT
ZONE #1, APPROPRIATING
560,000 TO FUND THE •
ASSESSMENT, AND •
IAUTHORIZING THE CITY MAN-
AGER TO EXECUTE A CON-
! TRACT FOR SAID ASSESSMENT.