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AN ORDINANCE BY THE CITY COUNCIL OF THE CITY OF DENTON, TEXAS,
CREATING A NEW CHAPTER 16 ENTITLED "FLOOD DAMAGE PREVENTION",
PROVIDING A SEVERABILITY CLAUSE AND DECLARING AN EFFECTIVE DATE
WHEREAS, the legislature of the State of Texas has delegated
to local governmental units the authority to adopt regulations
designed to minimize flood losses,
WHEREAS, much of the City of Denton is so situated that there
are flood hazard areas which are subject to periodic inundation re-
sulting in loss of life and property, health and safety hazards,
disruption of commerce and governmental services,extraordinary
public expenditures for flood protection and relief, and impair-
ment of the tax base all of which adversely affect the public
health, safety and general welfare, and
WHEREAS, such flood losses are caused by the cumulative effect
of obstructions in floodways which increases flood heights and
velocities, and the occupancy of flood hazard areas by uses vulner-
able to floods or hazardous to others inadequately elevated or
otherwise protected from flood damages,
NOW THEREFORE, THE COUNCIL OF THE CITY OF DENTON, TEXAS, HERE-
BY ORDAINS
That the Code of Ordinances of the City of Denton, Texas, be
and the same is hereby amended by creating a new Chapter 16, Arti-
cle I through Article VIII to be entitled Flood Damage Prevention,
which shall hereafter read as follows
ARTICLE I
SECTION 16 1 - STATEMENT OF PURPOSE
It is the purp�se of this ordinance to promote the public health,
safety and general elfare and to minimize public and private losses
due to flood condithons in specific areas by provisions designed to
(1) Protect human life and health,
(2) Minimize (expenditure of public money for costly flood
control projects,
(3) Minimize the need for rescue and relief efforts associated
with flooding and generally undertaken at the expense of
the general public,
(4) Minimize prolonged business interruptions,
(5) Minimize damage to public facilities and utilities such
as water and gas mains, electric, telephone and sewer
lines, streets and bridges located in flood plains,
(6) Help maintain a stable tax base by providing for the
sound use and development of flood -prone areas in such
a manner as to minimize future flood blight areas, and,
(7) Insure the potential buyers are notified that property
is in a flood area
SECTION 16 2 - METHODS OF REDUCING FLOOD LOSSES
In order to accomplish its purposes, this ordinance shall be
applied, administered and enforced as follows
(1) Restrict or prohibit uses that are dangerous to health,
safety or property in times of flood, or cause excessive
increases in flood heights or velocities,
(2) Require that uses vulnerable to floods, including facil-
ities which serve such uses, be protected against flood
damage at the time of initial construction,
(3) Control the alteration of natural flood plains, stream
channels, and natural protective barriers, which are in-
volved in the accommodation of flood waters,
(4) Control filling, grading, dredging and other development
which may increase flood damage,
(5) Prevent or regulate the construction of flood barriers
which will increase flood hazards to other lands,
(6) No permit shall be issued for the construction, alteration
or improvement of any property within a Floodway or Flood
Plain area, unless the same shall comply with the terms
hereof
(7) Areas within a Flood Plain, when dedicated to public use
as open space, green belts or parkways, or when permanently
and irrevocably reserved as privately owned space, green-
belts or parkways, shall conform to the city's plan of
development Such land may be included in the computation
of open space as gross density requirements of this ordin-
ance
ARTICLE II
DEFINITIONS
SECTION 16 3
Unless specifically defined below, words or phrases used in
this ordinance shall be interpreted to give them the meaning they
have in common usage and to give this ordinance its most reasonable
application
(1) Appeal - Means a request for a review of the City Engineer's
interpretation of any provision of this ordinance or a request for
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a variance
(2) Area of Shallow Flooding - Means a designated AO Zone
on a community's Flood Insurance Rate Map (FIRM) with base flood
depths from one to three feet This condition occurs where a
clearly defined channel does not exist, where the path of flood-
ing is unpredictable and indeterminate, and where velocity flow
may be evident
(3) Area of Shallow Flooding Hazard - is the land in the
flood plain within a community sub)ect to a one percent or greater
change of flooding in any given year
(4) Base Flood - means the flood having a one percent chance
of being equaled or exceeded in any given year
(S) Development - means any man-made change to improved or
unimproved real estate, including but not limited to buildings or
other structures, mining, dredging, filling, grading, paving, exca-
vation or drilling operations
(6) Encroachment Lines - Limits of obstruction to flood flows
These lines are generally parallel to the stream The lines are
established by assuming that the area landward (outside) of the en-
croachment lines will be ultimately developed in such a way that it
will not be available to convey flood flows If hydraulic 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 of more than
one (1) foot
(7) Existing Mobile Home Park or Mobile Home Subdivision -
means a parcel (or contigous parcels) of land divided into two or
more mobile home lots for rent or sale for which the construction
of facilities for servicing the lot on which the mobile home is 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) is completed before the effective date of
this ordinance
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(8) Expansion To An Existing Mobile Home Park or Mobile
Home Subdivision - means the preparation of additional sites by
the construction of facilities for servicing the lots on which
the mobile homes are to be affixed (including the installation
of utilities, either final site grading or pouring of concrete
pads, or the construction of streets)
(9) Flood or Flooding - means a general and temporary con-
dition of partial or complete inundation of normally dry land
areas from
(1) The overflow of inland or tidal waters
(2) The unusual and rapid accumulation or runoff of surface
waters from any source
(10) Flood Hazard Boundary Map (FHBM) - means an official map
of a community, issued by the Federal Insurance Administration,
where the areas within the boundaries of special flood hazards have
been designated as Zone A
(11) Flood Insurance Rate Map (FIRM) - means an official map
of a community, on which the Federal Insurance Administration has
delineated both the areas of special flood hazards and the risk
premium zones applicable to the community
(12) Flood Insurance Study - is the official report provided
by the Federal Insurance Administration The report contains flood
profiles, the water surface elevation of the base flood, as well as
the Flood Hazard Boundary-Floodway Map
(13) Floodway - means the channel of a stream and adjacent
land areas which are required to carry and discharge the flood water
of 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 This area is designated
by the symbols FW
(14) Flood Plain - The area outside the floodway which is still
subject to inundation by the regulatory flood This area is desig-
nated by FP
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(15) Habitable Floor - means any floor usable for living
purposes, which includes working, sleeping, eating, cooking, or
recreation, or a combination thereof A floor used for storage
purposes only is not a "habitable floor"
(16) Mean Sea Level - means the average height of the sea
for all stages of the tide
(17) Minimum Building Elevation - The elevation to which
uses regulated by this ordinance are required to be elevated or
flood proofed 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 estab-
lishment of floodways, 1 e , minimum building elevation equals
regulatory flood elevation plus one (1) foot
(18) Mobile Home - means a structure, transportable in one
or more sections, which is built on a permanent chassis and de-
signed to be used with or without a permanent foundation when con-
nected to the required utilities It does not include recreational
vehicles or travel trailers
(19) New Mobile Home Park or Mobile Home Subdivision - means
a parcel (or contiguous parcels) of land divided into two or more
mobile home lots for rent or sale for which the construction of
facilities for servicing the lot on which the mobile home is to
be affixed (including, at a minimum, the installation of utilities
either final site grading or the puring of concrete pads, and the
construction of streets) is completed on or after the effective
date of this ordinance
(20) 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 im-
pede, retard, or change the direction of the flow of water, either
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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
(21) Regulatory Flood - The regulatory flood is a flood
which is representative of large floods known to have occurred
generally in 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 re-
currence interval flood determined from an analysis of floods on a
particular stream and other streams in the same general region
(22) Start of Construction - means the first placement con-
struction of a structure (other than a mobile home) on a site, such
as the pouring of slabs or footings or any work beyond the stage of
excavation Permanent construction does not include land preparation
such as clearing, grading, and filling, nor does it include the in-
stallation of streets and/or walkways, nor does it include excavation
for a basement, footings, piers or foundations or the erection of
temporary forms, nor does it include the installation on the property
of accessory buildings, such as garages or sheds not occupied as
dwelling units or not as part of the main structure For a structure
(other than a mobile home) without a basement or poured footings,
the "start of construction" includes the first permanent framing or
assembly of the structure or any part thereof on its piling or foun-
dation For mobile homes not within a mobile home park or mobile
home subdivision, "start of construction" means the affixing of the
mobile home to its permanent site For mobile homes within mobile
home parks or mobile home subdivisions, "start of construction" is
the date on which the construction of facilities for serving the
site on which the mobile home is to be affixed (including, at a
minimum, the construction of streets, either final site grading or
the pouring of concrete pads, and installation of utilities) is
completed
(23) Structure - 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, and other similar items
(24) Substantial Improvement - Means any repair, recon-
struction, or improvement of a structure, the cost of which equals
or exceeds 50 percent of the market value of the structure either,
(1) before the improvement or repair is started, or (2) if the
structure has been damaged and is being restored, before the dam-
age occurred For the purposes of this definition "substantial
improvement" is considered to occur when the first alteration of
any wall, ceiling, floor, or other structural part of the building
commences, whether or not that alteration affects the external
dimensions of the structure The term does not, however, include
either (1) any project for improvement of a structure to comply
with existing state or local health, sanitary, or safety code
specifications which are solely necessary to assure safe living
conditions, or (2) any alteration of a structure listed on the
National Register of Historic Places or a State Inventory of
Historic Places
(25) Variance - Is a grant of relief to a person from the
requirements of this ordinance when specific enforcement would re-
sult in unnecessary hardship A variance, therefore, permits con-
struction, or development in a manner otherwise prohibited by this
ordinance
ARTICLE III
GENERAL PROVISIONS
SECTION 16 4 - LANDS TO WHICH THIS ORDINANCE APPLIES
This ordinance shall apply to all areas of special flood hazard
within the jurisdiction of the City of Denton
SECTION 16 5 - BASIS FOR ESTABLISHING THE AREAS OF SPECIAL
FLOOD HAZARD
The areas of special flood hazard identified by the Federal
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Insurance Administration on its Flood Hazard Boundary Map (FHBM),
Community No 48-0194, dated November 1, 1974, and any revisions
thereto are hereby adopted by reference and declared to be a part
of this ordinance Also included in this section for reference
shall be the final draft report for the Flood Insurance Rate Map
(FIRM)
SECTION 16 6 - ESTABLISHMENT OF DEVELOPMENT PERMIT
A development Permit shall be required to ensure conformance
with the provisions of this ordinance
SECTION 16 7 - COMPLIANCE
No structure or land shall hereafter be located, altered, or
have its use changed without full compliance with the terms of
this ordinance and other applicable regulations
SECTION 16 8 - ABROGATION AND GREATER RESTRICTIONS
This ordinance is not intended to repeal, abrogate, or impair
any existing easements, covenants, or deed restrictions However,
where this ordinance and another conflict or overlap, whichever
imposes the more stringent restrictions shall prevail
SECTION 16 9 - 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 under State
Statutes
SECTION 16 10 - WARNING AND DISCLAIMER OF LIABILITY
The degree of flood protection required by this ordinance is
considered reasonable for regulatory purposes and is based on
scientific and engineering considerations On rare occasions
greater floods can and will occur and flood heights may be in-
creased by man-made or natural causes This ordinance does not
imply that land outside the areas of special flood hazards or
uses permitted within such areas will be free from flooding or
flood damages This ordinance shall not create liability on the
part of the City of Denton or any officer or employee thereof for
any flood damages that result from reliance on this ordinance
or any administrative decision lawfully made thereunder
ARTICLE IV
ADMINISTRATION
SECTION 16 11 - DESIGNATION OF CITY ENGINEER
The City Engineer is hereby appointed to administer and im-
plement the provisions of this ordinance
SECTION 16 12 - DUTIES AND RESPONSIBILITIES OF THE CITY
ENGINEER
Duties and responsibilities of the City Engineer shall include,
but not be limited to, the following
(1) Maintain and hold open for public inspection all records
pertaining to the provisions of this ordinance,
(2) Review, approve or deny all applications for development
permits required by Section 16 6 of this ordinance,
(3) Review permits for proposed development to assure that
all necessary permits have been obtained from those Federal, State
or local governmental agencies from which prior approval is required,
(4) Where interpretation is needed as to the exact location of
the boundaries of the areas of special flood hazards (for example,
where there appears to be a conflict between a mapped boundary and
actual field conditions) the City Engineer shall make the necessary
interpretation,
(5) Assure that maintenance is provided within the altered
or relocated portion of said watercourse so that the flood carrying
capacity is not diminished,
(6) When base flood elevation data has not been provided in
accordance with Section 16 5, the City Engineer shall obtain, re-
view, and reasonably utilize any base flood elevation data avail-
able from a Federal, State, or other source, in order to administer
the provision of Article V
SECTION 16 13 - ZONING MAP FLOOD AREA DESIGNATIONS
(1) a The provisions of this section shall apply to all
lands within the city irrespective of Zoning Dis-
trict classification
tel:
b The flood plain areas within the jurisdiction of
this ordinance are hereby divided into two dis-
tricts Floodway Districts (FW) and Floodway
Fringe Districts (FF)
There shall be superimposed upon the official zon-
ing map the Flood Plain designation, as determined
by the flood insurance study and report hereinabove
defined
The outer boundary of Floodway Fringe District at
any point shall correspond to the elevation of a
minimum building elevation, less one foot of said
point Minimum building elevation shall be the
governing factor in locating the outer district
boundary on the zoning map and on the ground The
inner boundary corresponds to the boundary of the
Floodway district
The boundary of a Floodway District shall correspond
to the Floodway encroachment lines Boundaries of
a Floodway District shall be determined by scaling
distances on the official zoning map On the ground
the Floodway encroachment line shall be located by
measuring distances perpendicular from the Floodway
center line
In cases where Floodway encroachment lines have not
been delineated, the area below the minimum building
elevation shall be designated in the Floodway Dis-
trict until said encroachment lines can be determined
Where interpretation is necessary as to the exact
location of the boundaries of the Flood Plain Dis-
trict as shown on the Official Zoning Map the City
Engineer shall be consulted for guidance and direction
in determining the location in question Interpretation
beyond this point shall be made by the Board of Adjust-
ment after hearing testimony from all interested parties
(2) FLOODWAY DISTRICT USES
No use of land shall be permitted in a Floodway District
unless
a. The same is permitted within the zoning district in
which it is situated,
b Such use is not prohibited by any other ordinance,
and
c The same does not require structures, fill or the
storage of materials or equipment, provided, however,
that the following uses, when otherwise permitted
within the zoning district in which the same are
situated, shall be permitted upon application to the
City Engineer for a development permit as provided
in Section 16 14 of this ordinance, upon proof of
compliance with this ordinance
1 Accessory uses or structures
2 Circuses, carnivals and similar transient outdoor
amusement enterprises
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3 Marinas, boat rentals, docks, piers, and wharfs
4 Railroads, streets, bridges, utility transmission
lines and pipelines
5 Other uses, similar in nature, which are consistent
with the provisions of this ordinance
(3) FLOOD FRINGE DISTRICT USES
No use of land shall be permitted in a Flood Fringe Dis-
tract unless
a The same is permitted within the zoning district in
which it is situated,
b Such use is not prohibited by any other ordinance,
and
c The same does not require structures, fill or the
storage of materials or equipment, other than the
following uses
1 Any use permitted in this section
2 Any other non-structural use, provided that the
same is elevated above the minimum building
elevation and that a determination has first
been made by the City Engineer that such use
will not unduly restrict the capacity of the
channels or floodway of tributaries to the main
stream, drainage ditches, or any other drainage
facilities or systems
3 Structures constructed on fill, provided the
first floor or basement floor is above the
minimum building elevation Such fill shall
be made to an elevation no lower than one (1)
foot below the regulatory flood protection
elevation for the particular area and shall be
extended horizontally at such elevation at
least fifteen (15) feet beyond the limits of
any structure or building erected thereon
4 The following uses and structures shall be
permitted only upon issuance of a Development
Permit by the Board of Adjustment as provided
in the following section, Permit Procedures,
of this ordinance and subject to the following
provisions
1 Non-residential structures, if adequately
flood -proofed as approved by the City
Engineer to a point above the regulatory
flood protection elevation
si Uses listed in Section 16 13 hereof and
other similar uses which will not be sub-
ject to substantial flood damage and which
will not cause flood losses on other lands
or to the public These may include uses
which can be readily removed from flood
hazard areas during the times of flood
The Board may in the Development Permit
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allow such uses to be located at an ele-
vation below the regulatory flood pro-
tection elevation
SECTION 16 14 - PERMIT PROCEDURES
(1) Application for a Development Permit shall be presented
to the City Engineer on forms furnished by him and may include,
but not be limited to, plans in triplicate drawn to scale show-
ing the location, dimensions, and elevation of proposed landscape
alterations, existing and proposed structures, and the location
of the foregoing in relation to areas of special flood hazard
Additionally, the following information is required
a Elevation in relation to mean sea level, of the lowest
floor (including basement) of all proposed structures
as certified by a registered professional engineer or
registered public surveyor,
b Elevation in relation to mean sea level to which any
non-residential structure shall be flood proofed,
c A certificate from a registered professional engineer
or architect that the non-residential flood proofed
structure shall meet the flood proofing criteria of
Section 16 17(2),
d Description of the extent to which any watercourse or
natural drainage will be altered or relocated as a re-
sult of proposed development
e Typical valley cross -sections 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
f Plan (surface view) showing elevations or contours of
the ground, pertinent structure, fill or storage ele-
vations, size, location and special arrangement of
all proposed and existing structures on the site, lo-
cation and elevations or streets, water supply, sani-
tary facilities, photographs showing existing land uses
and vegetation upstream and downstream, soil types and
other pertinent information
g Profile showing the slope of the bottom of the channel
or flow line of the stream
h Specifications for building construction and materials
flood proofing, filling, dredging, grading, channel
improvement, storage of materials, water supply, and
sanitary facilities
(2) Approval or denial of a Development Permit by the City
Engineer shall be based on all of the provisions of this ordinance
and the following relevant factors
a The danger to life and property due to flooding or
erosion damage,
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b The susceptibility of the proposed facility and its
contents to flood damage and the effect of such dam-
age on the individual owner,
c The danger that materials may be swept onto other
lands to the injury of others,
d The compatibility of the proposed use with existing
and anticipated development,
e The safety of access to the property in times of flood
for ordinary and emergency vehicles,
f The costs of providing governmental services during
after flood conditions including maintenance and re-
pair of streets and bridges, and public utilities and
facilities such as sewer, gas, electrical, and water
systems
g The expected heights, velocity, duration, rate of rise
and sediment transport of the flood waters and the
effects of wave action, if applicable, expected at the
site,
h The necessity to the facility of a waterfront location,
where applicable,
i The availability of alternative locations, not subject
to flooding or erosion damage, for the proposed use,
j The relationship of the proposed use to the compre-
hensive plan for that area
SECTION 16 15 - VARIANCE PROCEDURES
(1) The Board of Adjustment as established by the Denton City
Council shall hear and render judgment on requests for variance
from the requirements of this ordinance
(2) The Board of Adjustment shall hear and render judgment
on an appeal only when it is alledged there is an error in any
requirement, decision, or determination made by the City Engineer
in the enforcement or administration of this ordinance
(3) Any person or persons aggrieved by the decision of the
Board of Adjustment may appeal such decision in the courts of
competent jurisdiction
(4) The City Engineer shall maintain a record of all actions
involving an appeal and shall report variances to the Federal In-
surance Administration upon request
(5) Variances may be issued for the reconstruction, rehabili-
tation, or restoration of structures listed on the National Register
of Historic Places of the State Inventory of Historic Places, with-
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out regard to the procedures set forth in the remainder of this
section
(6) Generally, variances may be issued for new construction
and substantial improvements to be erected on a lot of one-half
acre or less in size contiguous to and surrounded by lots with
existing structures constructed below the base flood level, pro-
viding the relevant factors in Section 16 13(3) have been fully
considered As the lot size increases beyond the one-half acre,
the technical justification required for issuing the variance
increases
(7) Upon consideration of the factors noted above and the
intent of this ordinance, the Board of Adjustment may attach such
conditions to the granting or variances as it deems necessary to
further the purpose and objectives of this ordinance which may
include
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 Flood proofing measures, as described in the Flood
Section 16 17 (2)
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 per-
mitted which, acting alone or in combination with exist-
ing or future uses, unduly effects the efficiency or the
capacity of the floodway or unduly increases flood
heights above the minimum building elevation Conside-
ration 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
(8) Variances shall not be issued within any designated flood -
way if any increase in flood levels during the base flood discharge
would result
(9) Prerequisites for Granting Variances
a Variances shall only be issued upon a determination
that the variance is the minimum necessary, consider-
ing the flood hazard, to afford relief
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be
b Variances shall only be issued upon (1) a showing
of good and sufficient cause, (2) a determination
that failure to grant the variance would result
in exceptional hardship to the applicant, and (3)
a determination that the granting of a variance
will not result in increased flood heights, addi-
tional threats to public safety, extraordinary
public expense, create nuisances, cause fraud on
or victimization of the public, or conflict with
existing local laws or ordinances
c Any applicant to whom a variance is granted shall
be given written notice that the structure will be
permitted to be built with a lowest floor elevation
no more than two (2) feet below the base flood
elevation, and that the cost of flood insurance will
be commensurate with the increased risk resulting
from the reduced lowest floor elevation
(10) Additional factors for consideration by the Board shall
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 on to other
lands or downstream to the in3ury of others
c The proposed water supply and sanitation systems
and the ability of these systems to prevent disease,
contamination and unsanitary conditions
d The susceptability 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 pro-
posed facility to the community
f The requirements of the facility for a waterfront
location
g The availability of alternative locations not sub-
ject to flooding for the proposed use
h The compatibility of the proposed use with existing
development and development anticipated in the fore-
seeable future
1 The relationship of the proposed use to the compre-
hensive plan and flood plain management program for
the area
3 The safety of access to the property in times of
flooding 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
1 Such other factors which are relevant to the pur-
pose of this ordinance
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ARTICLE V
PROVISIONS FOR FLOOD HAZARD REDUCTION
SECTION 16 16 - GENERAL STANDARDS
In all areas of special flood hazards the following provisions
are required
(1) All new construction and substantial improvements shall
be anchored to prevent flotation, collapse, or lateral movement of
the structure,
(2) All new construction or substantial improvements shall
be constructed by methods and practices that minimize flood damage,
(3) All new construction or substantial improvements shall be
constructed with materials and utility equipment resistant to flood
damage,
(4) All new and replacement water supply systems shall be de-
signed to minimize or eliminate infiltration of flood waters into
the system,
(5) New and replacement sanitary sewage systems shall be de-
signed to minimize or eliminate infiltration or flood waters into
the system and discharges from the systems into flood waters, and,
(6) On -site waste disposal systems shall be located to avoid
impairment to them or contamination from them during flooding
SECTION 16 17 - SPECIFIC STANDARDS
In all areas of special flood hazards where base flood elevation
data has been provided as set forth in Section 16 5, Section 16 12
(6), or Section 16 18(3) the following provisions are required
(1) Residential Construction - New construction or substantial
improvement of any residential structure shall have the lowest floor,
including basement, elevated one foot (1) above the base flood ele-
vation A registered professional engineer, architect, or land sur-
veyor shall submit a certification to the City Engineer that the
standard of this subsection, as proposed in Section 16 14(1)(a), is
satisfied
(2) Non-residential Construction - New Construction or sub-
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stantial improvement of any commercial, industrial or other non-
residential structure shall either have the lowest floor, including
basement, elevated to the level of the base flood elevation or, to-
gether with attendent utility and sanitary facilities, be flood
proofed so that below the base flood level the structure is water
tight 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 re-
gistered professional engineer or architect shall submit a certi-
fication to the City Engineer that the standards of this subsection
as proposed in Section 16 14(1)(c), are satisfied
(3) Mobile Homes
a No mobile homes shall be placed in a floodway, or if
applicable, a coastal high hazard area, except in an existing mobile
home park or existing mobile home subdivision
b All mobile homes shall be anchored to resist flotation,
collapse, or lateral movement Specific requirements shall be
(1) over -the -top ties at each of the four corners of the
mobile home, with two additional ties per side at
intermediate locations and mobile homes less than
50 feet long requiring one additional tie per side,
(ii) frame ties at each corner of the home with five
additional ties per side at intermediate points and
mobile homes less than 50 feet long requiring four
additional ties per side,
(111) all components of the anchoring system be capable
of carrying a force of 4,800 pounds,
(iv) any additions to the mobile home be similarly
anchored
c For new mobile home parks and subdivisions, for ex-
pansions to existing mobile home parks and subdivisions, for exist-
ing mobile home parks and subdivisions where the repair, recon-
struction or improvement of the streets, utilities and pads equals
or exceeds 50 percent of value of the streets, utilities and pads
before the repair, reconstruction or improvement has commenced,
and for mobile homes not placed in a mobile home park or subdivision
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require
(i) stands or lots are elevated on compacted fill
or on pilings so that the lowest floor of the
mobile home will be at or above the base flood
level A registered professional engineer,
architect, or land surveyor shall submit a
certificate to the City Engineer that the stan-
dard of this paragraph complies with Section
16 17(1) of this Article
(11) adequate surface drainage and access for a
hauler are provided, and
(ui) in the instance of elevation on pilings (1)
lots are large enough to permit steps, (2)
piling foundations are placed in stable soil
no more than ten feet apart, and (3) rein-
forcement is provided for pilings more than
six feet above the ground level
(4) Floodways
Floodways located within areas of special flood hazard
established in Section 16 5 are areas designated as floodways
Since the floodway is an extremely hazardous area due to the veloc-
ity of flood waters which carry debris, potential projectiles and
erosion potential, the following provisions shall apply
a Encroachments are prohibited, including fill, new con-
struction, substantial improvements and other developments unless
certification by a professional registered engineer or architect is
provided demonstrating that encroachments shall not result in any
increase in flood levels during occurence of the base flood discharge
b If Section 16 17 (4)(a) above is satisfied, all new
construction and substantial improvements shall comply with all
applicable flood hazard reduction provisions of Article 5
c Prohibit the placement of any mobile homes, except in
an existing mobile home park or subdivision
SECTION 16 18 - STANDARDS FOR SUBDIVISION PROPOSALS
(1) All subdivision proposals shall be consistent with Section
16 20 16 3 and 16 4 of this ordinance
(2) All proposals for the development of subdivisions shall
meet Development Permit requirements of Section 16 6, Section 16 14
and the provisions of Article 5 of this ordinance
(3) Base flood elevation data shall be generated for subdivi-
sion proposals and other proposed development which is greater than
the lesser of 20 lots or 3 acres, if not otherwise provided pur-
suant to Section 16 5, or Section 16 12(6) of this ordinance
(4) All subdivision proposals shall have adequate drainage
provided to reduce exposure to flood hazards or as outlined in
the storm sewer ordinance of the City of Denton
(5) All subdivision proposals shall have public utilities
and facilities such as sewer, gas, electrical and water systems
located and constructed to minimize flood damage
(6) The final plat for a subdivision shall have the base
flood contour line, the floodway contour line and the proposed
limit of fill contour line shown for the record
SECTION 16 19 - STANDARDS FOR AREAS OF SHALLOW FLOODING
(AO ZONES)
Located within the areas of special flood hazard established
in Section 16 5 are areas designated as shallow flooding These
areas have special flood hazards associated with base flood depths
of 1 to 3 feet where a clearly defined channel does not exist and
where the path of flooding is unpredictable and indeterminate,
therefore, the following provisions apply
(1) All new construction and substantial improvements of
residential structures shall have the lowest floor, including
basement, elevated above the crown of the nearest street to or
above the depth number specified on the community's FIRM
(2) All new construction and substantial improvements of
non-residential structures shall
(1) Have the lowest floor, including basement, ele-
vated above the crown of the nearest street or
above the depth number specified on the FIRM, or
(11) Together with attendant utility and sanitary
facilities be completely flood proofed to or about
that level so that any space below that level is
water tight with walls substantially impermeable
to the passage of water and with structural com-
ponents having the capability of resisting hydro-
static and hydrodynamic loads and effects of
buoyancy
(3) A registered professional engineer or architect shall
submit a certification to the City Engineer that the standards of
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