0161-062ORDINANCE NO. 161- 62
AN 4RDIMAACE AMENDING ORDINANCE RD. 161 OF THE
CITY OF 5DUTNLAEE, TFXAS. BY ADDING PARAGRAPH
13 TO SECTION VI. OF SAID ORDINANCE, SAID
PARAGRAPH 13 BEING "FLOOD HAZARD DI TRICTS*
THIS AMENDMENT ESTABLISHING FLOOD HAZARD DISTRICTS:
FW-FLOODWAY DISTRICT and FP-FLOOD PLAIN DISTRICT;
ESTABLISHING FLOOD HAZARD DISTRICT SOUROARIES;
REGULATING LAND USE, STRUCTURE DESIGN AND
C€NSTRUMON METHODS WITHIN SAID DISTRICTS;
PROVIDING FOR SPECIAL EXCEPTION PERMITS; PROVIDING
FOR APPEAL PROCEDURES; PROVIDING A PENALTY FOR
VIOLATION; PROVIDING A SEVERABILITY CLAUSE; AND
PROVIDING FOR PUBLICATION AND EFFECTIVE DATE.
WHEREAS, the City Council deems it necessary, to promote and
safeguard the public health, safety and general welfare, to regulate
flood hazard areas within the corporate limits of the City of
Southlake, Texas; and,
WHEREAS, the City Council, pursuant to the provisions of Chapter
4 Title 28 of Vernon's Annotated Civil Statutes of Texas as amended,
has caused exhaustive studios by the Consulting Engineers oflhe City,
received and considered such engineering studies, recommendations of
the Planning and Zoning Commission, and considered all information
received at public hearings conducted after due public notices;
NOW THEREFORE, be it enacted by the City Council of the City of
Southlak+e, Texas:
SECTION-1. Ordinance No. 161 of the City of Southloko, Texas is
hereby amended by including the following as Paragraph 13 of Section
VT. thereof: All provisions of Exhibit "A" attached hereto and made
a part hereof by referents. such Exhibit "A" being a 19 page printed
instrument prepared by Carter and B;urgess,iac., Engineers-Planners,
Fart Worth, Texas, signed for identification by the Mayor of the
City of Southlake, Texas.
SECTION._2. This ordinance is hereby declared to be cumulative
of the
provisions of any other applicable ordinance of the City of
Southlake. Texas.
SECTION. Any person violating or failing to comply with
any provisions of this ordinance shall be fined upon conviction,
not less than $1.00 nor more than $200.00 and each day any
violation of non-compliance conditions continues shall constitute
a separates offense. All other remedies provided by lax are also
reserved by the City of Southlake, Texas.
SECTION 4. It is hereby declared to be the intention of the City
Council of the City of Southlake, Texas, that the sections, paragraphs,
sentences, clauses and phrases of this ordinance are severable and if
any phrase, clause, sentence, paragraph or section hereof should be
declared unconstitutional, such unconstitutionality or invalidity
shall not Ofect any of the remaining phrases, clauses, sentences,
paragraphs or sections of this ordinance, since the same would have
been enacted by the City Council without the incorporation in this
ordinance of any such unconstitutional or invalid phrase, clause,
sentence, paragraph or section.
1E.CTION 6 The said Ordinance 161, except as amended by prior
amendments and this Ordinance no. 161 remains in effect in
all other respects as originally passed.
U TI4h 6. This ordinance shall take effect after its passage
and publicatib as required by law.
PASSED thi-s of 1974.
ATTEST:
FLOOD HAZARD DISTRICT ORDINANCE
FOR THE CITY OF
SOUTHLAKE, TEXAS
(AN AMENDMENT TO ZONING ORDINANCE N0.161)
PREPARED THROUGH THE COOPERATION
OF THE
DEPARTMENT OF COMMUNITY AFFAIRS
OF THE
STATE OF TEXAS
THE PREPARATION OF THIS REPORT WAS FINANCED IN PART
THROUGH A COMPREHENSIVE PLANNING GRANT FROM THE DE-
PARTMENT OF HOUSING AND URBAN DEVELOPMENT
EXHIBIT "A" TO ORDINANCE 161-62
SIGNED FOR ID TIFICATION:
ayor
BY
CARTER & BURGESS,INC.
ENGINEERS - PLANNERS
FORT WORTH, TEXAS
r
FLOOD HAZARD DISTRICT ORDINANCE
CITY OF SOUTHLAKE......... TEXAS
AN AMENDMENT TO ZONING ORDINANCE NO. 161
CONTENTS
Page No.
SECTION 1 -
FLOOD HAZARD DISTRICTS: "FW" - FLOODWAY DISTRICT;
AND "FP" - FLOOD PLAIN DISTRICT
1
1.1 PUR
POSE AND INTENT
1
1.2 METHODOLOGY AND REFERENCES USED TO ANALYZE AND
DEF
INE FLOOD HAZARDS AND FLOOD HAZARD DISTRICTS
3
1.3 APP
LICATION, ADMINISTRATION AND ENFORCEMENT
5
1.4 DES
IGNATION, DETERMINATION AND INTERPRETATION OF
FLOOD HAZARD DISTRICT BOUNDARIES
5
1.5 "FW
- FLOODWAY DISTRICT" USE REGULATIONS
8
1.5.1
Permitted Principal Uses
8
1.5.2
Special Exceptions
9
1.5.3
Prohibited Uses
10
1.6 "FP
- FLOOD PLAIN DISTRICT" USE REGULATIONS
11
1.6.1
Permitted Principal Uses
11
1.6.2
Special Exceptions
11
1.6.3
Prohibited Uses
13
1.7 SPECIAL PROVISIONS FOR FLOOD HAZARD DISTRICTS
13
1.7.1
Easements and Dedications
13
1.7.2
Density and Floor Area Ratio Bonuses; and
Computation of Open Space
.15
1.7.3
Fill
16
1.7.4
Buildings and Structures: Temporary and Permanent
17
1.7.5
Floodproofing
18
1.7.6
Storage of Materials and Equipment
19
1.7.7
Water Supply and Sanitary Sewage Facilities
19
1.7.8
Proof of Concurrence of Fill, Land Use or
Development by Other Agencies
20
CONTENTS (Continued) Pape No.
1.8 SPECIAL EXCEPTION PERMITS FOR FLOOD HAZARD DISTRICTS 20
1.8.1 Application and Procedures 20
1.8.2 Supplemental Information: Requirements 21
1.8.3 Factors for Consideration of Approval 23
1.8.4 Special Conditions or Requirements Which May Be
Attached and Made Part of An Approved Special
Use Permit 24
1.9 ABROGATION AND GREATER RESTRICTIONS 25
1.10 WARNING AND DISCLAIMER OF LIABILITY 25
1.11 DEFINITIONS 25
CITY OF SOUTHLAKE,..,.....TEXAS
SECTION 1 - FLOOD HAZARD DISTRICTS: "FW" - FLOODWAY DISTRICT AND "FP" -
FLOOD PLAIN DISTRICT:
The regulations governing the use of land, buildings and structures, or as
set forth elsewhere in the City's Zoning Ordinance when referred to in this
section, are the regulations of the "FW - Floodway District" and "FP - Flood
Plain District." Both districts are by nature interrelated and therefore
combined in this section.
1.1 PURPOSE AND INTENT. It has been determined that within the City of
Southlake, Texas, there exist flood hazard areas which are subject to
periodic inundation and which can result in loss of life and property,
cause disruption of commerce and governmental services and facilities,
induce extraordinary public expenditures for flood protection and relief
and impairment of the tax base - all of which adversely affect the public
health, safety and general welfare. It has further been determined that
such losses in flood hazard areas are caused by the cumulative effect of
obstructions in floodways which increase flood heights and velocities and
the occupancy of flood plains by uses vulnerable to floods or hazardous
to other inadequately elevated or otherwise unprotected uses from flood
damages.
It is the purpose and intent of this section, therefore, to promote and
safeguard the public health, safety and general welfare in minimizing
the aforedescribed losses by provisions designed to:
1.
a. Restrict or prohibit uses which are dangerous to health, safety
or property in times of flood or cause increased flood heights
or velocities;
b. Require that uses vulnerable to floods, including public facilities
which serve such uses, be provided with flood protection at the time
of initial construction or major expansions thereof;
c. Protect individuals in the acquisition or development of lands
which are generally unsuited for certain purposes because of
potential flood hazard;
d. Provide for the establishment of a comprehensive drainage plan
for the major watercourses, drainageways and greenbelts of the
City;
e. Insure the perpetuity, conservation and protection of watercourses,
drainageways and greenbelts throughout the City as a natural pro-
tection against hazards and losses connected with flooding.
In order to achieve the aforedescribed purposes, two interrelated
districts are established: "FW - Floodway District," which embraces
the channel of a watercourse, drainageway or greenbelt and adjacent
land areas on either side that are required to carry and discharge
the floodwater or flood flows with the regulatory flood - commonly
referred to as the "floodway," delineated by floodway encroachment
lines;" and the "FP - Flood Plain District," which delineates the
areas outside the floodway encroachment lines which are still subject
to inundation by the regulatory flood. These districts are superimposed
on the Zoning District Map and their provisions apply to all lands,
water areas and watercourses within the City, irrespective of the
2.
Zoning District classifications overlaid by the flood hazard districts.
The uses and special exceptions herein allowed in this section are the
uses of the "FW" and "FP" Districts to the extent they are not pro-
hibited by any other zoning district regulation or supplementary district
regulation of the zoning districts underlying said flood hazard district
boundaries.
1.2 METHODOLOGY AND REFERENCES USED TO ANALYZE AND DEFINE FLOOD HAZARDS
AND FLOOD HAZARD DISTRICTS. This ordinance uses a reasonable method
of analyzing flood hazards which are outlined as follows:
a. Selection of a regulatory flood which is based upon engineering
calculations which permit a consideration of such flood factors
as its expected frequency of occurrence, the area inundated and
the depth of inundation. The regulatory flood selected for this
ordinance is representative of large floods known to have occur-
red in this region and which are reasonably characteristic of
what can be expected to occur on the particular streams subject
to this ordinance. It is in the general order of a flood which
could be expected to occur on the average of once every 100
years (a one percent chance of occurring during any year).
b. Calculation of water surface profiles based upon a hydraulic
engineering analysis of the capacity of the stream channel and
overbank areas to convey the regulatory flood;
c. Computation of the floodway required to convey this flood without
increasing flood heights more than one (1) foot above the regu-
latory flood to an extent which would cause substantial upstream
or downstream damage to existing or reasonably anticipated future
development;
3.
d. Delineation of floodway encroachment lines within which no addi-
tional obstruction is permitted which would cause damage or would
inhibit the discharge of flood flows;
e. Delineation of the flood plain, i.e., that area outside the flood-
way encroachment lines but which is still subject to inundation
by the regulatory flood;
f. The following Flood Plain Information Reports were used in the
delineation of the Flood Hazard Districts and form the basis of
the "FW" and "FP" District boundaries. They are hereby attached
to and made a part of the Zoning District Map and Zoning Ordinance
by reference, including any subsequent revisions or amendments
updating said information that may occur from time to time. Such
reports shall be kept on file in the office of the City Secretary
for public inspection:
1) Flood Plain Information - Bear Creek, Dallas and Tarrant
Counties, Texas, dated June 1971, prepared by the Corps of
Engineers, U. S. Army, Fort Worth, Texas, District;
2) Flood Boundary Delineation: Map of Flood Prone Areas -
Grapevine and Colleyville Quadrangles 7.5 Minute Tonogranhic
Series (1959 Base Data, Photorevised in 1968) dated 19730
prepared by the Geological Survey, Water Resources Division,
of the U. S. Department of the Interior, Geological Survey,
Austin, Texas, District;
3) Federal Insurance Administration Flood Hazard Boundary Maps,
City of Southlake, Texas (Tarrant County), Nos. H 48-439-6485-01
through 10, dated February 15, 1974, as prepared by the office
of the Federal Insurance Administration of the U. S. Department
of Housing and Urban Development; and
4.
4) Updated Master Plan, Trinity River and Tributaries, Texas,
Grapevine Lake, Denton Creek, Elm Fork, Trinity River, July
25, 1973; prepared by U. S. Army District, Corps of Engineers,
Fort Worth, Texas.
1.3 APPLICATION, ADMINISTRATION AND ENFORCEMENT. No land, water, building
or structure shall hereafter be used and no building or structure shall
be located, extended, converted or undergo major structural alterations,
nor shall any building permit, fill permit or certificate of occupancy be
issued, nor shall any zoning district change or subdivision plat be
approved without full compliance with the terms and provisions of this
section and other applicable Zoning, Subdivision and Building Code
Regulations. The City Secretary, City Engineer and the Zoning Board of
Adjustment, when applicable, shall administer and enforce this section.
In administering this section, the City will coordinate its administra-
tion with affected neighboring jurisdictions, local, county, state and
federal agencies to assure compatibility of related flood control, open
space and flood plain management decisions and measures across juris-
dictional lines and conform with applicable laws, statutes and adminis-
trative rules and regulations at all governmental levels.
1.4 DESIGNATION, DETERMINATION AND INTERPRETATION OF FLOOD HAZARD
DISTRICT BOUNDARIES. There shall be superimposed upon the Official
Zoning District Map, as an overlay, the "FW - Floodway" and "FP -
Flood Plain" District boundary designations, as determined by the
Flood Plain Information Reports hereinabove described. The boundaries
thereof shall be determined by scaling distances on the Zoning District
Map. Where interpretation is required as to the exact location of the
boundaries of said districts then reference to the aforedescribed Flood
S.
Plain Information Reports or other updated surveys and studies using
controlling floodwater surface and land elevation data therefrom, plus
interpretation and review by the City Engineer shall be made for more
exact determinations. However, where a conflict arises between a
mapped boundary and existing on-site field conditions, or due to more
current updated information supplied by the land owner or City, then
the Zoning Board of Adjustment shall make and rule on the necessary
interpretation.
While the regulatory flood protection elevation, for any point in
question or dispute, shall be the governing factor in locating the
district boundary on the property in question, the land owner con-
testing any district boundary location shall be given an opportunity
to present his findings of fact to the Zoning Board of Adjustment
and submit his technical evidence, if so desired.
In any interpretation and application, the provisions of this section
shall be held to be minimum requirements and shall be liberally construed
in favor of the governing body and shall not be deemed a limitation or
repeal of any other powers granted by State Statutes.
Determinations of "FW" and "FP" District boundaries shall be made in
conformance with either or all of the following methods:
a. By a comprehensive engineering watershed study, using technical
and professionally acceptable hydrological and hydraulic criteria
and procedures, of all or a part of the land embraced within the
City's corporate limits and areas of extraterritorial jurisdic-
tion;
6.
b. By the owner's registered engineer when a subdivision plat and/or
zoning district change embracing residential, commercial or indus-
trial development is prepared for submission and approval by the
City or when a request for a building permit or fill permit is
made to the City by the Owner. The methodology used in such deter-
mination shall be the same as in paragraph a. above.
"FW" and "FP" district boundary lines shall correspond to the following:
1. The "FW - Floodway" district shall be bounded by the floodway
encroachment lines as shown on the zoning map, by scaling distances
therefrom. On the ground said boundaries shall be located by meas-
uring distances perpendicular to the floodway centerline. A reg-
istered land surveyor's or engineer's description of the alignment
of said centerline and limits of the floodway shall be attached by
reference to, and made a part of, the Official Zoning District Map,
and to any subdivision plat prepared, as such centerlines and flood-
way limits are ascertained. In no case shall the boundaries of any
"FW" District extend beyond the outer boundary of the "FP" District;
2. The outer "FP - Flood Plain" District boundaries shall correspond
to, and be the same as, the regulatory flood elevation existing at
the time of passage of this section or future amendments thereto.
This elevation is further defined as being the 100-year (or one
percent chance of occurring during any year) floodwater surface
elevation, and/or one (1) foot below the lowest minimum floor ele-
vation of a permitted building or structure, i.e., that elevation
to which uses regulated by this section are required to be elevated
or floodproofed. Said minimum floor elevation shall be the govern-
ing factor in locating the outer area boundary of the "FP" District,
7.
whereas the inner boundary shall correspond with the boundary of
the "FW" District.
3. In cases where the floodway encroachment lines which govern the
limits of the "FW" District have not been delineated, the land area
below the minimum floor elevation shall be designated as the floodway
elevation until said encroachment lines can be determined.
l.S "FW - FLOODWAY DISTRICT" USE REGULATIONS. The regulations set forth
herein are the regulations of the "FIV - Floodway District."
1.5.1 Permitted Principal Uses. The following open space uses shall be
permitted to the extent they are permitted within the Zoning
District in which the "FW" District is superimposed thereon, and
further provided that such uses do not require buildings, fill or
unsecured storage of equipment, machinery or materials.
a. Ranch and Agricultural Uses, such as: general farming;
pasture and grazing land; outdoor plant nurseries; horti-
culture; viticulture; field and truck farming; forestry; sod
farming; grain, crop, tree, orchard and vine farming and
harvesting; horse and livestock breeding; apiaries; poultry
yards; and fish hatcheries.
b. Streets; bridges; drives; roadways; parking and loading areas;
pedestrian overpasses; railroads; and helistops.
c. Public; semi-public and private park, recreation and open space
uses, such as: parks, playgrounds; parkways, greenbelts;
botanical gardens and arboretums; ponds and lakes; pedestrian
hiking paths; bicycle and equestrian bridle trails; swimming
pools and court games; playfields; picnic grounds; golf
courses; golf driving ranges; archery ranges; shooting
8.
i
preserves and game farms; target ranges; trap and skeet
ranges; hunting and fishing areas; bird and wildlife and
nature preserves; and overnight camping or tent grounds and
roadside parks and rest areas.
d. Residential Uses, such as: lawns; gardens; play areas; and
parking areas.
e. Essential Public Services, such as: underground gas distri-
bution mains; water mains and storm and sanitary sewers pro-
vided any pressure pumping facilities shall be located above
a floodway's designed water surface elevation, and further
provided any such installations are placed or located so as
to minimize flood damage; overhead telephone and electric
transmission lines provided the supports for same are located
outside the "FW" District boundaries on approved fill or out-
side the "FW" District.
f. Other uses and accessory uses of a similar nature and char-
aster to any of the uses described above which are consistent
with the general provisions set forth in this section and
permitted within their respective districts.
1.5.2 Special Exceptions. In order to provide for certain uses which,
because of their unique character cannot be given unconditional
usage within the "FW" District, the Zoning Board of Adjustment
may, in conformance with this section, authorize and grant the
following "special exceptions" contingent upon reasonable and
appropriate safeguards, and where allowed in the zoning district
underlying the "FW" District in which they are to be located:
9.
a. Circuses, carnivals, fair grounds and other similar transient
outdoor amusement enterprises and activities;
b. Drive-in theaters, new and used car and recreational vehicle
sales lots, temporary roadside stands for the sale of produce,
signs and billboards;
c. Storage yards for equipment, machinery or materials provided
such storage is sufficiently secured from flotation at all
times or can be readily removed through ample warning prior
to a flood;
d. Animal kennels, horse stables and show rings;
e. Properly constructed and anchored boat docks, wharfs, piers,
bulkheads, marinas, or other similar waterfront structures.
1.5.3 Prohibited Uses. The following uses are expressly prohibited:
a. Solid fences or walls which are perpendicular or near per-
pendicular to the boundaries of the "FW' District and any
other fence or wall less than (70%) open positioned at the
same general angle.
b. Operative electrical equipment or transformers, unless ele-
vated above the regulatory flood protection elevation.
c. Unsecured (flotable) storage of junk, materials or equipment.
d. Feeding or disposal of garbage, rubbish, rash or offal.
e. Sanitary land fills and any other obstructive structures.
f. Residential, commercial, industrial and community facility
buildings and structures not expressly permitted.
g. Unpermitted fill or encroaching development.
h. Any other uses not otherwise permitted.
10.
1
1.6 "FP - FLOOD PLAIN DISTRICT" USE REGULATIONS. The regulations set forth
herein are the regulations of the "FP - Flood Plain District."
1.6.1 Permitted Principal Uses. The following uses shall be permitted
to the extent they are permitted within the zoning district in
which the "FP" district is superimposed thereon, and further
provided that such uses do not require buildings or structures,
fill, storage of equipment, machinery or materials unless in con-
formance with this section.
a. Any open space or nonstructural use permitted in the "FW -
Floodway District."
b. Any structural use, provided such use is elevated above the
minimum floor elevation (regulatory flood protection eleva-
tion).
c. Residential, commercial, industrial and community facility
buildings or structures, including mobile homes, constructed
or placed on fill and floodproofed, provided they shall have
the lowest floor not less than one (1) foot above regulatory
flood protection elevation and further provided that any such
permitted fill shall be placed to an elevation not lower than
one (1) foot below the regulatory flood protection elevation
for the particular area and such fill shall be extended hori-
zontally at said elevation not less than 15 feet beyond the
limits of the perimeter of any building or structure erected
thereon.
1.6.2 Special Exceptions. In order to provide for certain uses which
because of their unique character cannot be given unconditional
usage within the "FP" District, the Zoning Board of Adjustment
11.
may, in conformance with this section, authorize and grant the
following "special exceptions" contingent upon reasonable and
appropriate safeguards and upon determination of said exceptions
not creating additional flood hazards to other private or public
interests, and when allowed in the zoning district underlying the
"FP" District in which they are to be located:
a. Nonresidential and accessory buildings or structures (either
temporary or permanent) provided such are adequately flood-
proofed or otherwise protected, in conformance with the
requirements outlined in the "Special Provisions" paragraph
of this subsection, to a point above the regulatory flood
protection elevation.
b. Any "special exception" use listed under the "FW" District
regulations and other similar uses permitted in the zoning
district underlying the "FP" District in which they are to
be located, provided such will not be subjected to substantial
flood damage nor cause additional flood hazards to other public
or private interests. These may include uses which can be
readily removed from flood hazard areas during time of flood.
In granting approval of any "special use" the Zoning Board of
Adjustment may allow such uses to be located at an elevation
below the regulatory flood protection elevation upon just and
reasonable cause.
c. Filling of land for any purpose.
d. Solid fences or walls which are parallel to the flowline of
the floodway and flood plain.
12.
e. Levees, dikes, berms or similar floodproofing means.
1.6.3 Prohibited Uses. The following uses are expressly prohibited:
a. Operative electrical equipment or transformers unless elevated
above the regulatory flood protection elevation.
b. Unsecured (flotable) storage of junk, materials or equipment
below the regulatory flood protection elevation.
c. Feeding or disposal of garbage, rubbish, trash or offal.
d. Obstructive structures or buildings which hinder flood water
flowage or which create additional flood hazards to other
public or private interests.
e. Hospitals, nursing homes, boarding schools and orphanages,
sanitariums, hotels, motels, detention centers, fraternities
and sororities, dormitories and other uses of a similar nature
and character.
f. Any other use not otherwise permitted.
1.7 SPECIAL PROVISIONS FOR FLOOD HAZARD DISTRICTS. The following special
provisions apply to all lands and water areas within the "FW" and "FP"
flood hazard districts:
1.7.1 Easements and Dedications. Maintenance and access easements, or
dedications, for waterways, drainageways, greenbelts and the
like shall be required so as to insure maintainability, and access
to flood hazard areas. Likewise, easements or land dedications
along either or both sides of waterways, drainageways, greenbelts,
etc. for open space developments in conformance with the City's
Comprehensive Plan and Zoning Ordinance shall be encouraged. Any
such easements and/or land dedications shall meet the following
minimum requirements:
13.
G
a. All land within the waterway which lies between the controlling
banks of waterways or drainageways shall be dedicated to the
City so as to allow the proper protection and preservation
thereof to insure unrestricted water drainage and flowage.
b. Additional easements or dedications of land along and to
the waterways and drainageways, where required, shall meet
the following requirements:
1) A maintenance easement, with a minimum width of fifty (50)
feet, shall be conveyed to the City on each side of the
required dedicated area indicated in paragraph a. above.
Land dedication may be substituted in lieu of an easement
at the Owner's option.
2) An open space easement or dedication with a total width of
200 feet along major creeks, watercourses and drainageways
and 150 feet along minor drainageways, exclusive of the
area dedicated in paragraph a. above, shall also be encour-
aged. Said easement or dedication may be coincidental
with the maintenance easement described in paragraph b.l)
above and may be located entirely on one side of the
dedicated land described in paragraph a. or divided
equally between two sides. When such dedications or ease-
ments are provided, the provisions of subsection 1.7.2
may be applied.
3) Access easements of not less than 40 feet in width shall
be required from adjacent public use areas and/or public
streets at horizontal intervals of not less than 500 feet,
for access to maintenance and/or open space easements or
14.
dedications described in paragraphs b.l) and 2) above,
so as to provide sufficient ingress and egress of trucks
and equipment for maintaining flood hazard areas, and for
public access to any public park or open space use created
or maintained. Land dedication may be substituted in lieu
of an easement at the Owner's option.
4) Reasonable variations and modifications of the above
requirements may be allowed by the Zoning Board of
Adjustment upon written recommendations and concurrence
by the City Engineer and City Planning and Zoning Commis-
sion (or other designated board or commission such as a
Parks and Recreation Board) when it can be determined that
lesser or greater easement widths or dedications than
herein required would be sufficient to achieve the intended
purposes of both the Flood Hazard Zoning Districts and that
of the City's Comprehensive Plan.
c. Timing of conveyance of required easements or land dedications
for maintenance, access, and/or open space purposes may be
made by the land owner at any time and consummated upon approval
and acceptance by the City; however, no building permits, certi-
ficates of occupancy or fill permits shall be issued nor shall
final approval of any change in zoning classification be made,
nor shall any plat revision or final plat approval be given
until any required easements or land dedications are made by
the land owner in conformance with this section.
1.7.2 Density and Floor Area Ratio Bonuses; and Computation of Open Space.
Land within the Flood Hazard Districts either conveyed as an easement
15.
or dedicated to the City by the owner, in accordance with this
section, may be counted as open space for computing density and/or
open space requirements with regard to the City's Zoning Ordinance.
Density and floor area ratio bonuses may be granted by the City's
Planning and Zoning Commission to the land owner when such ease-
ments and/or dedications are made. The extent of such bonuses
shall be dependent upon the nature and amount of land granted by
easements or dedications and the type of development proposed.
However, in no case shall the density bonus be less than the density
of development recommended by the City's Comprehensive Plan if
development were to take place without such required easements,
or open space dedications.
1.7.3 Fill. An application requesting any fill material proposed to be
deposited or placed within the Flood Hazard Districts must first
be submitted to the City Engineer for review and recommendation
prior to the consideration of and issuance of a fill permit by
the Zoning Board of Adjustment. Prior to the issuance of such
permit the proposed fill must be shown by the owner to have some
beneficial purpose and the amount thereof shall not be greater
than is necessary to achieve such stated purpose, as demonstrated
by a plan drawn to scale of not less than 111=1001, along with a
sufficiently detailed narrative describing the type, quantity,
compaction and dimensions of the fill material - including the
uses to which the fill material will be put. Such fill or other
materials shall be adequately protected against erosion or slippage
by either riprap, bulkheading and/or vegetative cover, whichever
is approved as being the most reasonable and adequate method by
the City Engineer.
16.
1.7.4 Buildings and Structures: Temporary and Permanent. No building
or structure shall be designed or occupied for human habitation
within the Flood Hazard District unless such meets the require-
ments of this section. The design of any permitted building or
structure shall be such as to afford a low flood damage potential..
Permitted buildings placed or constructed within the Flood Hazard
Districts shall be positioned and oriented so as to offer the
minimum degree of obstruction to the flow of flood waters.
Whenever possible, buildings and structures shall be positioned
with their longitudinal axis parallel to the direction of flood
flow; and so far as practicable, buildings and structures shall be
placed approximately on the same flood flow lines as those of any
adjoining permitted structures on either end.
All permitted buildings, structures and mobile homes shall be
firmly secured or anchored to prevent flotation, collapse or
lateral movement which may result in damage to other structures,
restriction of bridge or culvert openings and other narrow sec-
tions of the watercourse, drainageway, creek, greenbelt and the
like.
Service facilities such as electrical and heating equipment shall
be constructed or placed at or above the regulatory flood protec-
tion elevation for the particular area.
Permitted major repairs, alterations or enlargements of existing
buildings or structures within the Flood Hazard Districts shall
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use construction materials and utility equipment that are resis-
tant to flood damage and employ construction methods and practices
that will minimize flood damage.
Construction methods and practices that will minimize flood damage
shall be employed on all new construction and such shall be pro-
tected from flood damage.
1.7.5 Floodproofing. All structures permitted to be erected or con-
structed pursuant to the provisions of this section shall be
floodproofed. Floodproofing measures such as the following shall
be designed consistent with the flood protection elevation for
the particular area, flood velocities, durations, rate of rise,
hydrostatic and hydrodynamic forces and other factors associated
with the regulatory flood. The Zoning Board of Adjustment may
require that the applicant submit a plan or document certified
by a registered professional engineer that the floodproofing
measures are consistent with the regulatory flood protection ele-
vation and associated flood factors for the particular area. The
following floodproofing measures may be required, without limita-
tion because of specific enumeration:
a. Anchorage to resist flotation and lateral movement.
b. Installation of watertight doors, bulkheads and shutters.
c. Reinforcement of walls to resist water pressure.
d. Use of paints, membranes or mortars to reduce seepage of
water through walls.
e. Addition of mass or weight to structures to resist flotation.
f. Installation of pumps to lower water levels in structures.
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g. Construction of water supply and waste treatment systems so
as to prevent the entrance of flood waters.
h. Pumping facilities for subsurface external foundation wall
and basement floor pressures.
i. Construction to resist rupture or collapse caused by water
pressure or floating debris.
j. Cutoff valves on sewer lines or the elimination of gravity
flow basement drains.
k. Elevation of structures and uses to the regulatory flood
protection elevation.
1. Floodproofing by use of levees, dikes, berms or similar means
must meet the requirements of state statutes and shall not
create additional flood hazards to other public or private
interests.
1.7.6 Storage of Materials and Equipment. The storage or processing of
materials that are buoyant, flammable, explosive or could be
injurious to human, animal or plant life in time of flooding is
expressly prohibited.
Storage of other material or equipment when otherwise permitted
may be allowed if such is not subject to major damage by floods,
and is firmly secured to prevent flotation, collapse or lateral
movement or such can be readily removable from the area within
the limited time available after flood warning.
1.7.7 Water Supply and Sanitary Sewage Facilities. New or replacement
water supply and sanitary sewage facilities shall be designed and
installed to minimize or eliminate infiltration of flood waters
into water systems and discharges from sewage systems into flood
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waters. Land developments with planned on-site waste disposal sys-
tems shall be approved only where the system can be designed,
located and constructed or placed so as to avoid impairment or con-
tamination of such facilities during flooding. These requirements
are applicable as a part of subdivision plat approval and/or in
connection with the issuance of a building permit.
1.7.8 Proof of Concurrence of Fill, Land Use or Development, by Other
Agencies. In cases where the use of land, placement of fill or
other development is proposed in a designated Flood Hazard District,
the City or Zoning Board of Adjustment may, at its discretion,
require proof of concurrence by the Water Rights Commission and/or
the Texas Water Development Board Pursuant to V.T.C.S. and the
Texas Water Code. The City and/or Zoning Board of Adjustment shall
adhere to all Texas statutory and constitutional requirements when
rendering any decision or issuing any applicable permit.
1.8 SPECIAL EXCEPTION PERMITS FOR FLOOD HAZARD DISTRICTS.
1.8.1 Application and Procedures. Application for any special use listed
listed in this subsection as requiring a "Special Exception Permit"
may be allowed only upon application by the land owner to the
Zoning Administrator, on forms furnished by said person, and upon
issuance of a "Special Exception Permit" by the Zoning Board of
Adjustment. Upon receipt of the application, the Zoning Admin-
istrator shall forthwith submit one copy to the City Engineer (for
his review and recommendation to the Zoning Board of Adjustment) and
one copy to the Zoning Board of Adjustment. One copy shall be kept
on file in the office of the City Secretary for purposes of general
2U.
public information. The Board shall conduct its review and investi-
gation and pass on the application's approval or disapproval in
accordance with the established procedures set forth herein and
elsewhere described in the City's Zoning Ordinance.
1.8.2 Supplemental Information: Requirements. Upon receipt of an appli-
cation for a "Special Use Permit" involving land use, placement
of fill, construction of levees, dikes, berms or similar flood-
proofing means, construction or alteration of new or existing
buildings and structures including their accessory uses or storage
of materials and equipment, the Board may, prior to rendering a
decision thereon and upon recommendation from the City Engineer:
a. Require the applicant to submit, where applicable, plans in
triplicate drawn to scale of not less than 111=100' in plan
and other appropriate scale drawings showing the nature,
location, dimensions and elevation of the lot, existing or
proposed structures, fill, storage of materials, floodproofing
measures and the relationship of the above to the location of
the channel and floodway and the regulatory flood elevation.
b. Transmit where necessary one copy of the information described
in section a. to any other designated person or agency from
which the Board of Adjustment may request expert technical
assistance in evaluating the proposed project in relation to
flood heights and velocities, the seriousness of flood damage
to the use, the adequacy of the plans for protection and other
technical matters.
c. Require, where special circumstances necessitate more detailed
information, the applicant to furnish the following additional
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information as deemed necessary by the Board for the evaluation
of the effects of the proposed use upon flood flows and other
factors necessary to render a decision on the suitability of
the proposed use:
1) A typical valley cross-section showing the channel of the
stream, elevation of land areas adjoining each side of the
channel, cross-sectional areas to be occupied by the
proposed development, and high water information.
2) Plan (surface view) showing elevations or contours of the
ground; delineation of the floodway encroachment lines and
"FP" District boundaries, when involved; pertinent struc-
tures, fill, or storage elevations; size, location and
spatial arrangement of all proposed and existing structures
on the site; location and elevations of streets, water
supply, sanitary facilities; photographs showing existing
land uses and vegetation upstream and downstream; and
soil types and other pertinent information.
3) Profile showing the slope of the bottom of the channel or
flow line of the stream; and water surface elevation of
the 100-year regulatory flood, from official maps and
data.
4) Specifications for building construction and materials,
£loodproofing, filling, dredging, grading, channel improve-
ment, storage of materials, water supply and sanitary
facilities.
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1.8.3 Factors For Consideration of Approval. In passing upon such
applications, the Zoning Board of Adjustment shall give due
consideration to the following:
a. The danger to life and property due to increased flood heights
or velocities caused by encroachments.
b. The danger that materials may be swept onto other lands or
downstream to the injury of others.
c. The proposed water supply and sanitation systems and the ability
of these systems to prevent disease, contamination and unsani-
tary conditions.
d. The susceptibility of the proposed facility and its contents to
flood damage and the effect of such damage on the individual
owner.
e. The importance of the services provided by the proposed facility
to the community.
f. The requirements of the facility for a waterfront or flood
plain location.
g. The availability of alternative locations not subject to
flooding for the proposed use.
h. The compatibility of the proposed use with existing develop-
ment and development anticipated in the foreseeable future.
i. The relationship of the proposed use to the comprehensive plan
and flood plain management program for the area.
j. The safety of access to the property in times of flood or for
ordinary emergency vehicles.
k. The expected heights, velocity, duration, rate of rise and
sediment transport of the flood waters expected at the site.
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1. Such other factors which are relevant to the purpose of this
section.
1.8.4 Special Conditions or Requirements Which May Be Attached and Made
Part of an Approved Special Use Permit. Upon due consideration of
the factors listed above and the purposes and intent of this section,
the Zoning Board of Adjustment may attach such reasonable conditions
and safeguards to the granting of any Special Use Permit as it deems
necessary to further said ordinance purposes and intent. These
conditions and safeguards, without specific enumeration, may
include but need not be limited to:
a. Modification of waste disposal and water supply facilities.
b. Limitations on periods of use and operation.
c. Imposition of operational controls, sureties and deed
restrictions.
d. Requirements for construction of channel modifications, dikes,
levees and other protective measures.
e. Floodproofing measures, as described in this subsection.
f. No structure (temporary or permanent), fill, including fill
for roads and levees, deposit, obstruction, storage of materials
or equipment, or other uses shall be permitted which, acting
alone or in combination with existing or future uses, unduly
affects the efficiency or the capacity of the floodway or
unduly increases flood heights above the minimum building
elevation. Consideration of the effects of a proposed use
shall be based on a reasonable assumption that there will be
an equal degree of encroachment extending for a significant
reach on both sides of the stream, waterway, drainage way or
greenbelt.
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g. Proof of concurrence by the Texas Water Rights Commission
and/or the Texas Water Development Board Pursuant to their
authorities specified in V.T.C.S. and the Texas Water Code,
for the use of land, placement of fill or other proposed devel-
opment of a permanent or temporary nature within a flood
hazard area.
1.9 ABROGATION AND GREATER RESTRICTIONS. It is not intended by this section
to repeal, abrogate or impair any existing easements, covenants, or deed
restrictions. However, where this section imposes greater restrictions,
the provisions of this section shall prevail. All other ordinances or
parts of ordinances inconsistent with this section are hereby repealed
and superseded to the extent of the inconsistency only.
1.10 WARNING AND DISCLAIMER OF LIABILITY. The degree of flood protection
required by this section is considered reasonable for regulatory purposes
and is based on sound engineering and scientific methods of study and
application. Larger floods than herein described and provided for may
occur on rare occasions or the flood height may be increased by man-made
or natural causes, such as bridge or culvert openings becoming restricted
by debris. This ordinance does not imply that areas outside "floodway"
and "flood plain" district boundaries or land uses permitted within such
districts will be free from flooding or flood damages. This ordinance
shall not create a liability on the part of the City or any officer or
employee or paid consultant thereof for any flood damages that may result
from reliance on or compliance with this ordinance, or any administrative
decision lawfully rendered thereunder.
1.11 DEFINITIONS. Unless specifically defined below, words or phrases used
in this section shall be interpreted so as to give them the same meaning
25.
as they have in common usage and so as to give this section its most
reasonable application:
1.11.1 Buildings and Structures. Anything constructed or erected, on
the ground or attached to the ground, including but without
limiting the generality of the foregoing: buildings, factories,
sheds, cabins, mobile homes, bridges, towers, streets and other
similar items.
1.11.2 Easement. A right, either in the public generally or in private
entities or persons, to the use of a piece or parcel of land for
a special purpose, including the location of utilities, storm
drains or access, which right may include the use of the surface,
subsurface and/or the air space over such land.
1.11.3 Easement, Maintenance. An easement to provide for the maintain-
ability of all or part of the floodway and/or flood plain.
1.11.4 Easement, Access, Watercourse and Greenbelt. An easement for
access to the floodway and/or flood plain and to provide for
the conservation of drainageways, waterways and greenbelts
throughout the City.
1.11.5 Encroachment Lines. Limits of obstruction to flood flows. These
lines are generally parallel to the stream. The lines are estab-
lished by assuming that the area landward (outside) of the
encroachment lines will ultimately be developed in such a way
that it will not be available to convey flood flows. If hydrau-
lic efficiency of the floodway is maintained by protecting it
against unnecessary encroachments, it will be adequate to convey
the regulatory flood without resulting in an,increase in flood
elevations which would cause damage to existing or future devel-
opment.
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1.11.6 Equal Degree of Encroachment. A standard applied to the evalua-
tion of the effects of special exceptions on increases in flood
heights. It assumes that an encroachment if permitted may
confer on all property owners on both sides of the stream an
equal right to encroach to the same degree within that reach.
Since the factors affecting hydraulic efficiency are usually not
uniform within a reach, this will usually not result in equal
distances between encroachment lines and the sides of the stream.
1.11.7 Flood. A temporary rise in stream flow or stage that results
in water overtopping its banks and inundating areas adjacent to
the channel.
1.11.8 Floodway. The channel of a stream, creek, watercourse or drain-
ageway and adjacent land areas which are required to carry and
discharge the flood water or flood flows of any river or stream
associated with the regulatory flood with an allowable maximum
increase in water surface elevation above the regulatory flood
of one (1) foot.
1.11.9 Flood Plain. That area outside the floodway which is still
subject to inundation by the regulatory flood.
1.11.10 Floodproofing. A combination of structural provisions, changes,
or adjustment to properties and structures subject to flooding
primarily for the reduction or elimination of flood damages to
properties, water and sanitary facilities, structures, and
contents of buildings in a flood hazard area.
1.11.11 Minimum Floor Elevation. The lowest building floor elevation
to which uses regulated by this ordinance are required to be
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elevated or floodproofed. This elevation would be equal to the
elevation that could be reached by the regulatory flood if it
occurred under conditions existing at the time this ordinance
was passed, plus one (1) foot to allow for encroachments permitted
by the establishment of floodways, i.e., Minimum Floor Elevation
equals Regulatory Flood Elevation plus one (1) foot.
1.11.12 Obstruction. Any dam, wall, wharf, embankment, levee, dike,
pile, abutment, projection, excavation, channel rectification,
bridge conduit, culvert, building, wire, fence, rock, gravel,
refuse, fill, structure or matter in, along, across or projecting
into any channel, watercourse or regulatory flood hazard area
which may impede, retard or change the direction of the flow of
water, either in itself or by catching or collecting debris
carried by such water, or that is placed where the flow of water
might carry the same downstream to the damage of life or property.
1.11.13 Person. Any natural person, firm, partnership, association or
corporation; however, this definition does not include any
governmental unit.
1.11.14 Reach. A hydraulic engineering term to describe longitudinal
segments of a stream or river. A reach will generally include
the segment of the flood hazard area where flood heights are
primarily controlled by man-made or natural obstructions or
constructions. In an urban area an example of a reach would be
the segment of a stream or river between two consecutive bridge
crossings.
1.11.15 Regulatory Flood. The regulatory flood is a flood which is rep-
resentative of large floods known to have occurred generally in
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t
the area and reasonably characteristic of what can be expected
to occur on a particular stream. The regulatory flood generally
has an average frequency in the order of the 100-year recurrence
interval flood (one percent chance of occurring during any year)
determined from an analysis of floods on a particular stream and
other streams and water impoundments in the same general region.
1.11.16 Regulatory Flood Protection Elevation. The elevation to which
the lowest floor of uses regulated by this ordinance are required
to be elevated or floodproofed.
1.11.17 Structure. See "Buildings and Structures."
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