0271
ORDINANCE NO. 271
FLOOD HAZARD PREVENTION ORDINANCE
OUTLINE
ARTICLE I STATUTORY AUTHORIZATION, FINDING OF FACT,PURPOSE
AND OBJECTIVES ................................1D
Section A Staturtory Authorization ......................1D
Section B Findings of Fact ..............................1D
Section C Methods of Reducing Flood Losses ..............1D
Section D Statement of Purpose ..........................2D
ARTICLE 2 DEFINITIONS ...................................2D
ARTICLE 3 GENERAL PROVISIONS ............................SD
Section A Lands to Which This Ordinance Applies SD
Section B Basis For Establishing The Areas Of Special
Flood Hazard ..................................SD
Section C Establishment of Development Permit SD
Section D Compliance 5D
Section E Abrogation and Greater Restrictions 5D
Section F Interpretation ................................SD
Section G Warning And Disclaimer of Liability 6D
ARTICLE 4 ADMINISTRATION ................................6D
Section A Designation Of Local Administrator 6D
Section B Duties And Responsibilities ...................6D
Section C Permit Procedures .............................7D
Section D Variances Procedures ..........................8D
ARTICLE 5 PROVISIONS FOR FLOOD HAZARD REDUCTION 9D
Section A General Standards .............................9D
Section B Specific Standards ...........................10D
1. Resdential Construction ......................lOD
2. Non-Residential Construction .................10D
3. Mobile Homes .................................11D
4. Floodways ....................................11D
Section C Standards For Areas of Shallow Flooding 12D
Section D Standards For Subdivisions Proposals 13D
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ARTICLE I
STATUTORY AUTHORIZATION, FINDINGS OF FACT, PURPOSE AND METHODS
SECTION A. STATUTORY AUTHORIZATION
The Legislature of the State of Texas has in V. T. A. S. delegated
the responsibility to local governmental units to adopt regulations
designed to minimize flood losses. Therefore, the City Council of
City of Southlake, Texas does ordain as follows:
SECTION B. FINDINGS OF FACT
(1) The flood hazard areas of Southlake are subject to periodic
inundation which results in loss of life and property, health and
safety hazards, disruption of commerce and governmental services,
and extraordinary public expenditures for flood protection and relief,
all of which adversely affect the public health, safety and general
welfare.
(2) These flood losses are created by the cumulative effect of
obstructions in flood plains which cause an increase in flood
heights and velocities, and by the occupancy of flood hazard areas
by uses vulnerable to floods and hazardous to other lands because
they are inadequately elevated, flood-proofed, or otherwise pro-
tected from flood damage.
SECTION C. STATEMENT OF PURPOSE
It is the purpose of this ordinance to promote the public health,
safety and general welfare and to minimize public and private
losses due to flood conditions in specific areas by provisions
designed to:
(1) The protect human life and health;
(2) To minimize expenditure of public money for costly flood
control projects;
(3) To minimize the need for rescue and relief efforts
associated with flooding and generally undertaken at the
expense of the general public;
(4) To minimize prolonged business interruptions;
(5) To 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) To 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) To insure the potential buyers are notified that property
is in a flood area.
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SECTION D. METHODS OF REDUCING FLOOD LOSSES
In order to accomplish its purposes, this ordinance uses the follow-
ing methods:
(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
facilities 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
involved in the accomodation 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 unnaturally divert flood waters or which may
increase flood hazards to other lands.
ARTICLE 2
DEFINITIONS
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 applica-
tion.
APPEAL---means a request for a review of the Southlake City Admin-
istrator's interpretation of any provisions of this ordinance or
a request for a variance.
AREA OF SHALLOW FLOODING---means a designated AO, AH, or VO Zone
on a community's Flood Insurance Rate Map (FIRM) with a one to
three feet where a clearly defined channel does not exist, where
the path of flooding is unpredictable and where velocity flow
may be evident. Such flooding is characterized by ponding or sheet
flow.
AREA OF SPECIAL FLOOD HAZARD---is the land in the flood plain with-
in a community subject to a one percent or greater chance of flooding
in any given year. The area may be designated as Zone A on the
FHBM. After detailed ratemaking has been completed in preparation
for publication of the FIRM, Zone A usually is refined into Zones
A, A0, AH, Al-99, V0, or V1-30.
BASE FLOOD---means the flood having a one percent chance of being
equalled or exceeded in any given year.
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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, excavation
or drilling operations.
EXISTING 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 pouring of concrete pads, and the
construction of streets) is completed before the effective date
of this ordinance.
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 the pouring of concrete pads, or the con-
struction of streets).
FLOOD OR FLOODING---means a general and temporary condition 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.
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.
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.
FLOOD INSURANCE STUDY---is the official report provided by the
Federal Insurance Administration. The report contains flood pro-
files, the water surface elevation of the base flood, as well as the
Flood Hazard Boundary-Floodway Map.
FLOODWAY---means the channel of a river or other watercourse and
the adjacent land areas that must be reserved in order to dis-
charge the base flood without cumulatively increasing the water
surface elevation more than one food.
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".
HIGHEST ADJACENT GRADE---means the highest natural elevation of the
ground surface prior to construction next to the proposed walls of
a structure.
MEAN SEA LEVEL---means the average height of the sea for all stages
of the tide.
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MOBILE HOME---means a structure, transportable in one or more
sections, which is built on a permanent chassis designed to be used
with or without a permanent foundation when connected to the
required utilities. It does not include recreational vehicles
or travel trailers.
MEAN HIGHER HIDE TIDE---The mean higher high tide is the average
high tide reached over a period of a lunar cycle, roughly a
period of 19 years.
TEXAS OPEN BEACHES ACT---This statue, enacted by the Texas
Legislature in 1959, prohibits encroachment by private owners
on the Gulf of Mexico.
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 pouring of concrete pads, and
the construction of streets) is completed on or after the
effective date of this ordinance.
START OF CONSTRUCTION---means the first placement of permanent
construction 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 installation 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 foundation.
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 servi-
cing 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.
STRUCTURE---means a walled and roofed building that is prin-
cipally above ground, as well as a mobile home.
SUBSTANTIAL IMPROVEMENT---means any repair, reconstruction, 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
damage 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 dim-
ensions of the structure.
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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.
VARIANCE---is a grant of relief to a person from the requirements
of this ordinance when specific enforement would result in
unnecessary hardship. A variance, therefore, permits construction
or development in a manner otherwise prohibited by this ordinance.
ARTICLE 3
GENERAL PROVISIONS
SECTION A. LAND TO WHICH THIS ORDINANCE APPLIES
This ordinance shall apply to all areas of special flood hazard
within the jurisdiction of Southlake.
SECTION B. BASIS FOR ESTABLISHING THE AREAS OF SPECIAL FLOOD
HAZARD
The areas of special flood hazard identified by the Federal
Insurance Administration in a scientific and engineering
report entitled "The Flood Insurance Study for the City of South-
Lake", dated July 5, 1982, with accompanying Flood Insurance
Rate Maps and Flood Hazard Boundary-Floodway Maps and any revision
thereto are hereby adopted by reference and declared to be a
part of this ordinance.
SECTION C. ESTABLISHMENT OF DEVELOPMENT PERMIT
A Development Permit shall be required to ensure conformance
for flood prone areas, with the provisions of this ordinance.
SECTION D. 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 E. ABROGATION AND GREATER RESTRICTIONS
This ordinance is not intended to repeal, abrogate, or impair
any existing easements, convenants, or deed restrictions.
However, where this ordinance and another conflict or overlap,
whichever imposes the more stringent restrictions shall prevail.
SECTION F. INTERPRETATION
In the interpretation and application of this ordinance, all
provisions shall be: (1) considered as minimum requirements;
(2) liberally constructed in favor of the governing body; and
(3) deemed neither to limit nor repeal any other powers granted
under State statutes.
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SECTION G. 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 Southlake or any officer or employee or consultant thereoff
for any flood damages that result from reliance on this ordinance
or any administrative decision lawfully made thereunder.
ARTICLE 4
ADMINISTRATION
SECTION A. DESIGNATION OF CITY ADMINISTRATOR
The City Administrator is hereby appointed to administer and
implement the provisions of this ordinance.
SECTION B. DUTIES AND RESPONSIBILITIES OF THE CITY ADMINISTRATOR
Duties and responsibilities of the City Administrator shall include,
but not be limited to:
(1) Maintain and hold open for public inspection all records
pertaining to the provisions of this ordinance;
(2) Review, approve or deny all application for development
permits required by Article 3, Section C 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 re-
quired;
(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 Administrator shall
make the necessary interpretation. The person contesting the
location of the boundary shall be given a reasonable opportunity
to appeal the interpretation as provided in Section D (2) of this
Article.
(5) Notify adjacent communities and the Texas Federal Emergency
Management Agency prior to any alteration or relocation of a
watercourse, and submit evidence of such notification to the
Federal Insurance Administration;
(6) Assure that maintenance is provided by the property owner
within the altered or relocated portion of said watercourse so
that the flood carrying capacity is not diminished.
(7) When base flood elevation data has not been provided in
accordance with Article 3, Section B, the City Administrator
shall obtain, review, and reasonably utilize any base flood
elevation data available from a Federal, State, or other source,
in order to administer the provision of Article S.
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SECTION C. PERMIT PROCEDURES
(1) Application for a Development Permit shall be presented to
the City Administrator on forms furnished by him and may include,
but not be limited to, plans in duplicate drawn to scale showing
the locations, 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;
b. Elevation in relation to mean sea level to which any non-
residential structure shall be floodproofed;
c. A certificate from a registered professional engineer or
architect that the non-residential floodproofed structure shall
meet the floodproofing criteria of Article 5, Section B (2);
d. Description of the extent to which any watercourse or natural
drainage will be altered or relocated as a result of proposed
development.
(2) Approval or denial of a Development Permit by the City
Administrator 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;
b. The susceptibility of the proposed facility and its contents
to flood damage and the effect of such damage 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 and
after flood conditions including maintenance and repair of
streets and bridges, and public utilities and facilities such
as sewer, gas, electrical, and water systems.
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 comprehensive
plan for that area.
SECTION D. VARIANCES PROCEDURES
(1) The Zoning Board of Adjustments as established by City
Council shall hear and render judgement on requests for variances
from the requirements of this ordinance.
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(2) The Zoning Board of Adjustments shall hear and render
judgement on an appeal only when it is alleged there is an error
in any requirement, decision, or determination made by the
City Administrator in the enforcement or administration of this
ordinance.
(3) Any person or persons aggrieved by the decision of the
Zoning Board of Adjustments may appeal such decisions in the
courts of competent jurisdiction.
(4) The City Administrator shall maintain a record of all actions
involving an appeal and shall report variances to the Federal
Insurance Administration upon request.
(S) Variances may be issued for the reconstruction,
rehabilitation or restoration of structures listed on the
National Register of Historic Places or the State Inventory
of Historic Places, without regard to the procedures set forth
in the remainder of this section.
(6) Upon consideration of the factors noted above and the intent
of this ordinance, the Zoninq Board of Adjustments may attach
such conditions to the granting of variances as it deems
necessary to further the purpose and objectives of the ordinance
(Article 1, Sections C and D).
(7) Variances shall not be issued within any disignated floodway
if any increase in flood levels during the base flood discharne
would result.
(8) Prerequisites for granting variances:
a. Variances shall only be issued upon a determination that the
variance is the minimum necessary, considering the flood hazard,
to afford relief.
b. Variances shall only be issued upon (i) a showing of good
and sufficient cause, (ii) a determination that failure to
grant the variance would result in exceptional hardship to the
applicant, and (iii) a determination that the grantinq of a
variance will not result in increased flood heights, additional
threats to public safety, extraordinary public expense, created
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 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.
ARTICLE 5
PROVISIONS FOR FLOOD HAZARD REDUCTION
SECTION A. 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 contruction 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 designed
to minimize or eliminate infiltration of flood waters into the
system;
(5) New and replacement sanitary sewage systems shall be designed
to minimize or eliminate infiltration of flood waters into the
system and discharges from the systems into flood waters; and,
(6) On site waster disposal systems shall be located to avoid
impairment to them or contamination from them during flooding.
SECTION B. SPECIFIC STANDARDS
In all areas of special flood hazards where base flood elevation
data has been provided as set forth in (i) Article 3, Section B,
(ii) Article 4, Section B, (7), or (iii) Article 5, Section D,
(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 to or above the base flood
elevation, A registered professional engineer, architect or
land surveyor shall submit a certification to the City Administrator
that the standard of this subsection, as proposed in Article 4, Section
C (1) (a), is satisfied.
(2) Non-residential Construction-New Construction or substantial
improvement of any commercial , industrail or other non-residential
structure shall either have the lowest floor, including basement,
elevated to the level of the base flood elevation or, together
with attendent utility and sanitary facilities, be floodproofed
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
hydristatic and hadrodynamic loads and effects of buoyancy. A
registered professional engineery or architect shall submit a
certification to the City Administator that the standards of this
subsection as proposed in Article 4, Section C (1) (c), are
satisfied.
(3) Mobile Homes-
a. No mobile home shall be place 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:
(i) 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 for additional ties per side;
(iii) all components of the anchoring system be capable of
carrying a force of 4,800 bounds;
in
(iv) any additions to the mobile home be similarly anchored.
C. For new mobile home parks and subdivisions; for expansions
to existing mobile home parks and subdivisions; for existing
mobile home parks and subdivisions where the repair, reconstruction
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 improvements has commenced;
and for mobile homes not placed in a mobile home park or
subdivision require;
(4) Floodways-located within areas of special flood hazard
established in Article 3, Section B are areas designated as
floodways, Since the floodway is an extremely hazardous area
due to the velocity of flood waters which carry debris, potential
projectiles and erosion potential, the following provisions
shall apply:
a. Encroachments are prohibited, including fill, new construction,
substantial improvements and other developments unless
certification by a professional registered engineer or architect
is provided demonstrating that encroashments shall not result in
any increase in flood levels during occurence of the base flood
discharge.
b. If Article 5, Section B (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 C. STANDARDS FOR AREAS OF SHALLOW FLOODING (AO ZONES)
Located within the aresa of special flood hazard established in
Article 3 Section B 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 have the lowest floor (including basement) elevate
above the highest adjacent grade at least as high as the depth
number specified in feet on the community's FIRTH (at least two
if no depth number is specified).
(2) All new construction and substantial improvements of non-
residential structures:
(i) have the lowest floor (including basement) elevated above the
highest adjacent grade at least as high as the depth number
specified in feet on the community's FIRM (at least two feet if
no depth number is specified), or;
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(ii) together with attendant utility and sanitary facilities be
designated so that below the base flood level the structure is
watertight with walls substantially impermeable to the passage
of water and with structural components having the capability
of resisting hydrostatic and hydrodynamic loads of effects of
buoyancy.
(3) A registered professional engineer or achitect shall submit
a certification to the City Administrator that the standards
of this Section, as proposed in Article 4 Section C (1) (a) are
satisfied.
(4) Require within Zones AH and A0, adequate drainage paths
around structures on slopes, to guide floodwaters around and
away from proposed structures.
SECTION D. STANDARDS FOR SUBDIVISION PROPOSALS
(1) All subdivision proposals shall be consistent with Article 1,
Sections B,C and D of this ordinance.
(2) All proposals for the development of subdivisions shall meet
Development Permit requirements of Article 3, Section C, Article 4,
Section C, and the provisions of Article 5 of this ordinance.
(3) Base flood elevation data shall be provided for subdivision
proposals and other proposed development which is greater than the
lesser of 50 lots or 5 acres, if not otherwise provided pursuant
to Article 3, Section B or Article 4, Section B (7) of this
ordinance.
(4) All subdivision proposals shall have adequate drainage
provided to reduce exposure to flood hazards.
(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.
It is hereby found and declared by the City of Southlake that
severe flooding has occurred in the past within it jurisdiction
and will certainly occur within the future; that flooding is likely
to result in infliction of serious personal injury or death,
and is likely to result in substantial injury or destruction of
property within its jurisdiction; in order to effectively comply
with minimum standards for coverage under the National Flood
Insurance Program; and in order to effectively remendy the situation
described herein, it is necessary that this ordinance become
effective immediately. Therefore, an emergency is hereby declared
to exist, and this ordinance, being necessary for the immediate
preservation of the public peace, health and safety, shall be in
full force and effect from and after its passage.and approvdl.
APPROVED:
"
Mayor
c~ I
PASSED:
DATE:
CERTIFICATE
I, the undersigned, 4,&, , do hereby
certify that the above is a true and q rrect copy of an ordinance
duly adopted by the at a regular
meeting duly convened at the 101117J Al on u. •Z _
( ecretary ^r ^Q ;
(SEAL)