HomeMy WebLinkAbout2018-11-05-Ordinance 2905_Flood Plain ManagementORDINANCE NO.2905
AN ORDINANCE TO AMEND CHAPTER 306,FLOOD PLAIN MANAGEMENT,
CITY OF WAUKEE,IOWA,BY AMENDING AND REPLACING CHAPTER 306 FLOOD
PLAIN MANAGEMENT
BE IT ORDAINED by the Council of the City of Waukee:
FLOODPLAIN MANAGEMENT ORDINANCE
tt306.1:Definitions.Unless specifically defined below,words or phrases used in this Ordinance shall
be interpreted so as to give them the meaning they have in common usage and to give this Ordinance
its most reasonable application.
APPURTENANT STRUCTURE —A structure which is on the same parcel of the property as the
principal structure to be insured and the use of which is incidental to the use of the principal structure
BASE FLOOD -The flood having one (I)percent chance of being equaled or exceeded in any given
year.(Also commonly referred to as the "100-year flood").
BASE FLOOD ELEVATION (BFE)—The elevation floodwaters would reach at a particular site
during the occurrence of a base flood event.
BASEMENT -Any enclosed area of a building which has its floor or lowest level below ground level
(subgrade)on all sides.Also see "lowest floor."
DEVELOPMENT -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,drilling
operations or storage of equipment or materials."Development"does not include "minor projects"or
"routine maintenance of existing buildings and facilities"as defined in this section.It also does not
include gardening,plowing,and similar practices that do not involve filling or grading.
ENCLOSED AREA BELOW LOWEST FLOOR —The floor of the lowest enclosed area in a building
when all the following criteria are met:
a.The enclosed area is designed to flood to equalize hydrostatic pressure during flood events with
walls or openings that satisfy the provisions of Section 306.7(B)4a)of this Ordinance,and
b.The enclosed area is unfinished (not carpeted,drywalled,etc.)and used solely for low damage
potential uses such as building access,parking or storage,and
c.Machinery and service facilities (e.g.,hot water heater,furnace,electrical service)contained in
the enclosed area are located at least one (I)foot above the base flood elevation,and
d.The enclosed area is not a "basement"as defined in this section.
EXISTING CONSTRUCTION -Any structure for which the "start of construction"commenced
before the effective date of the first floodplain management regulations adopted by the community.
EXISTING FACTORY-BUILT HOME PARK OR SUBDIVISION -A factory-built home park or
subdivision for which the construction of facilities for servicing the lots on which the factory-built
homes are to be affixed (including at a minimum,the installation of utilities,the construction of streets,
and either final site grading or the pouring of concrete pads)is completed before the effective date of
the first floodplain management regulations adopted by the community.
EXPANSION OF EXISTING FACTORY-BUILT HOME PARK OR SUBDIVISION -The
preparation of additional sites by the construction of facilities for servicing the lots on which the
factory-built homes are to be affixed (including at a minimum,the installation of utilities,the
construction of streets,and either final site grading or the pouring of concrete pads).
FACTORY-BUILT HOME -Any structure,designed for residential use which is wholly or in
substantial part,made,fabricated,formed or assembled in manufacturing facilities for installation or
assembly and installation,on a building site.For the purpose of this Ordinance factory-built homes
include mobile homes,manufactured homes,and modular homes;and also include "recreational
vehicles"which are placed on a site for greater than 180 consecutive days and not fully licensed for
and ready for highway use.
FACTORY-BUILT HOME PARK -A parcel or contiguous parcels of land divided into two or more
factory-built home lots for sale or lease.
FIVE HUNDRED (500)YEAR FLOOD —A flood,the magnitude of which has a two-tenths (0.2)
percent chance of being equaled or exceeded in any given year or which,on average,will be equaled
or exceeded at least once every five hundred (500)years.
FLOOD -A general and temporary condition of partial or complete inundation of normally dry land
areas resulting from the overflow of streams or rivers or from the unusual and rapid runoff of surface
waters from any source.
FLOOD INSURANCE RATE MAP (FIRM)-The official map prepared as part of (but published
separately from)the Flood Insurance Study which delineates both the flood hazard areas and the risk
premium zones applicable to the community.
FLOOD INSURANCE STUDY (FIS)—A report published by FEMA for a community issued along
with the community's Flood Insurance Rate Map(s).The study contains such background data as the
base flood discharge and water surface elevations that were used to prepare the FIRM.
FLOODPLAIN -Any land area susceptible to being inundated by water as a result of a flood.
FLOODPLAIN MANAGEMENT -An overall program of corrective and preventive measures for
reducing flood damages and promoting the wise use of floodplains,including but not limited to
emergency preparedness plans,flood control works,floodproofing and floodplain management
regulations.
FLOODPROOFING -Any combination of structural and nonstructural additions,changes,or
adjustments to structures,including utility and sanitary facilities,which will reduce or eliminate flood
damage to such structures.
FLOODWAY -The channel of a river or stream and those portions of the floodplains adjoining the
channel,which are reasonably required to carry and discharge flood waters or flood flows so that
confinement of flood flows to the floodway area will not cumulatively increase the water surface
elevation of the base flood by more than one (I)foot.
FLOODWAY FRINGE -Those portions of the Special Flood Hazard Area outside the floodway.
HIGHEST ADJACENT GRADE —The highest natural elevation of the ground surface prior to
construction next to the proposed walls of a structure
HISTORIC STRUCTURE -Any structure that is:
a.Listed individually in the National Register of Historic Places,maintained by the Department
of Interior,or preliminarily determined by the Secretary of the Interior as meeting the
requirements for individual listing of the National Register;
b.Certified or preliminarily determined by the Secretary of the Interior as contributing to the
historical significance of a registered historic district or a district preliminarily determined by
the Secretary to qualify as a registered historic district;
c.Individually listed on a state inventory of historic places in states with historic preservation
programs which have been approved by the Secretary of the Interior;or,
d.Individually listed on a local inventory of historic places in communities with historic
preservation programs that have been certified by either i)an approved state program as
determined by the Secretary of the Interior or ii)directly by the Secretary of the Interior in
states without approved programs.
LOWEST FLOOR -The floor of the lowest enclosed area in a building including a basement except
when the criteria listed in the definition of Enclosed Area below Lowest Floor are met.
MAXIMUM DAMAGE POTENTIAL USES -Hospitals and like institutions;buildings or building
complexes containing documents,data,or instruments of great public value;buildings or building
complexes containing materials dangerous to the public or fuel storage facilities;power installations
needed in emergency or other buildings or building complexes similar in nature or use.
MINOR PROJECTS -Small development activities (except for filling,grading and excavating)valued
at less than $500.
NEW CONSTRUCTION -(new buildings,factory-built home parks)-Those structures or
development for which the start of construction commenced on or after the effective date of the first
floodplain management regulations adopted by the community.
NEW FACTORY-BUILT HOME PARK OR SUBDIVISION -A factory-built home park or
subdivision for which the consnuction of facilities for servicing the lots on which the factory-built
homes are to be affixed (including at a minimum,the installation of utilities,the construction of streets,
and either final site grading or the pouring of concrete pads)is completed on or after the effective date
of the effective date of the first floodplain management regulations adopted by the community.
RECREATIONAL VEHICLE -A vehicle which is:
a.Built on a single chassis;
b.Four hundred (400)square feet or less when measured at the largest horizontal projection;
c.Designed to be self-propelled or permanently towable by a light duty truck;and
d.Designed primarily not for use as a permanent dwelling but as a temporary living quarters for
recreational,camping,travel,or seasonal use.
ROUTINE MAINTENANCE OF EXISTING BUILDINGS AND FACILITIES —Repairs necessary to
keep a structure in a safe and habitable condition that do not trigger a building permit,provided they
are not associated with a general improvement of the structure or repair of a damaged structure.Such
repairs include:
a.Normal maintenance of structures such as re-roofing,replacing roofing tiles and replacing
siding;
b.Exterior and interior painting,papering,tiling,carpeting,cabinets,counter tops and similar
finish work;
c.Basement sealing;
d.Repairing or replacing damaged or broken window panes;
e.Repairing plumbing systems,electrical systems,heating or air conditioning systems and
repairing wells or septic systems.
SPECIAL FLOOD HAZARD AREA (SFHA)-The land within a community subject to the "base
flood".This land is identified on the community's Flood Insurance Rate Map as Zone A,A1-30,AE,
AH,AO,AR,and/or A99.
START OF CONSTRUCTION -Includes substantial improvement,and means the date the
development permit was issued,provided the actual start of construction,repair,reconstruction,
rehabilitation,addition,placement,or other improvement,was within 180 days of the permit date.The
actual start means either the first placement or permanent construction of a structure on a site,such as
pouring of a slab or footings,the installation of pile,the construction of columns,or any work beyond
the stage of excavation;or the placement of a factory-built home on a foundation.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 part of
the main structure.For a substantial improvement,the actual start of construction means the first
alteration of any wall,ceiling,floor,or other structural part of the building,whether or not that
alteration affects the external dimensions of the building.
STRUCTURE -Anything constructed or erected on the ground or attached to the ground,including,
but not limited to,buildings,factories,sheds,cabins,factor-built homes,storage tanks,grain storage
facilities and/or other similar uses.
SUBSTANTIAL DAMAGE -Damage of any origin sustained by a structure whereby the cost of
restoring the structure to its before damage condition would equal or exceed fifty (50)percent of the
market value of the structure before the damage occurred.Volunteer labor and donated materials shall
be included in the estimated cost of repair.Substantial damage also means flood-related damages
sustained by a structure on two separate occasions during a 10-year period for which the cost of repairs
at the time of such flood event,on the average,equals or exceeds 25 percent of the market value of the
structure before the damage occurred.Volunteer labor and donated materials shall be included in the
estimated cost of repair.
SUBSTANTIAL IMPROVEMENT -Any improvement to a structure which satisfies either of the
following criteria:
l.Any repair,reconstruction,or improvement of a structure,the cost of which equals or exceeds
fifty (50)percent of the market value of the structure either (i)before the "start of construction"
of the improvement,or (ii)if the structure has been "substantially damaged"and is being
restored,before the damage occurred.
The term does not,however,include any project for improvement of a structure to correct
existing violations of state or local health,sanitary,or safety code specifications which have
been identified by the local code enforcement official and which are the minimum necessary to
assure safe living conditions.The term also does not include any alteration of an "historic
structure",provided the alteration will not preclude the structure's designation as an "historic
structure".
2.Any addition which increases the original floor area of a building by 25 percent or more.All
additions constructed after the effective date of the first floodplain management regulations
adopted by the community shall be added to any proposed addition in determining whether the
total increase in original floor space would exceed 25 percent.
VARIANCE -A grant of relief by a community from the terms of the floodplain management
regulations.
VIOLATION -The failure of a structure or other development to be fully compliant with the
community's floodplain management regulations.
5306.2.Statutory Authority,Findings of Fact and Purpose.
A.The Legislature of the State of Iowa has in Chapter 414,Code of Iowa,as amended,delegated the
power to cities to enact zoning regulations to secure safety from flood and to promote health and
the general wel fare.
B.Findings of Fact
1.The flood hazard areas of the City of Waukee are subject to periodic inundation which can
result 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
impairment of the tax base all of which adversely affect the public health,safety and general
welfare o f the community.
2.These flood losses,hazards,and related adverse effects are caused by:(i)The occupancy of
flood hazard areas by uses vulnerable to flood damages which create hazardous conditions as a
result of being inadequately elevated or otherwise protected from flooding and (ii)the
cumulative effect of obstructions on the floodplain causing increases in flood heights and
velocities.
3.This ordinance relies upon engineering methodology for analyzing flood hazards which is
consistent with the standards established by the Department of Natural Resources.
C.Statement of Purpose
It is the purpose of this Ordinance to protect and preserve the rights,privileges and property of the City
of Waukee and its residents and to preserve and improve the peace,safety,health,welfare,and comfort
and convenience of its residents by minimizing those flood losses described in Section 306.2(B)I of
this Ordinance with provisions designed to:
1.Reserve sufficient floodplain area for the conveyance of flood flows so that flood heights and
velocities will not be increased substantially.
2.Restrict or prohibit uses which are dangerous to health,safety or property in times of flood or
which cause excessive increases in flood heights or velocities.
3.Require that uses vulnerable to floods,including public facilities which serve such uses,be
protected against flood damage at the time of initial construction or substantial improvement.
4.Protect individuals from buying lands which may not be suited for intended purposes because
of flood hazard.
5.Assure that eligibility is maintained for property owners in the community to purchase flood
insurance through the National Flood Insurance Program.
I3306.3.General Provisions
A.Lands to Which Ordinance Apply
The provisions of this Ordinance shall apply to all lands within the jurisdiction of the City of
Waukee shown on the Official Floodplain Zoning Map as being within the boundaries of the
Floodway,Floodway Fringe,General Floodplain and Shallow Flooding (Overlay)Districts,as
established in Section 306.3.
B.Establishment of Official Floodplain Zoning Map
The Flood Insurance Rate Map (FIRM)for Dallas County and Incorporated Areas,City of Waukee,
Panels 19049C0220F,0240F,0335F,0345F,0355F,dated December 7,2018,which were prepared as
part of the Flood Insurance Study for Dallas County,is (are)hereby adopted by reference and declared
to be the Official Floodplain Zoning Map.The flood profiles and all explanatory material contained
with the Flood Insurance Study are also declared to be a part of this ordinance.
C.Rules for Interpretation of District Boundaries
The boundaries of the zoning district areas shall be determined by scaling distances on the Official
Floodplain Zoning Map.When an interpretation is needed as to the exact location of a boundary,the
Administrative Official shall make the necessary interpretation.The Board of Adjustment shall hear
and decide appeals when it is alleged that there is an error in any requirement,decision,or
determination made by the Administrative Official in the enforcement or administration of this
Ordinance.
D.Compliance
No snucture or land shall hereafter be used and no structure shall be located,extended,converted or
structurally altered without full compliance with the terms of this Ordinance and other applicable
regulations which apply to uses within the jurisdiction of this Ordinance.
E.Abrogation and Greater Restrictions
It is not intended by this Ordinance to repeal,abrogate or impair any existing easements,covenants,or
deed restrictions.However,where this Ordinance imposes greater restrictions,the provision of this
Ordinance shall prevail.All other ordinances inconsistent with this Ordinance are hereby repealed to
the extent of the inconsistency only.
F.Interpretation
In their interpretation and application,the provisions of this Ordinance 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.
G.Warning and Disclaimer of Liability
The standards required by this Ordinance are considered reasonable for regulatory purposes.This
Ordinance does not imply that areas outside the designated Floodplain (Overlay)District areas will be
free from flooding or flood damages.This Ordinance shall not create liability on the part of the City of
Waukee or any officer or employee thereof for any flood damages that result from reliance on this
Ordinance or any administrative decision lawfully made there under.
FL Severability
If any section,clause,provision or portion of this Ordinance is adjudged unconstitutional or invalid by
a court of competent jurisdiction,the remainder of this Ordinance shall not be affected thereby.
5306.4.Administration
A.A ointment Duties and Res onsibilities of Administrative Official
1.The Administrative Official is hereby appointed to implement and administer the provisions of
this Ordinance and will herein be referred to as the Administrator.
2.Duties and responsibilities of the Administrator shall include,but not necessarily be limited to
the following:
a.Review all floodplain development permit applications to assure that the provisions of this
Ordinance will be satisfied.
b.Review floodplain development applications to assure that all necessary permits have been
obtained from federal,state and local governmental agencies including approval when
required from the Department of Natural Resources for floodplain construction.
c.Record and maintain a record of (i)the elevation (in relation to North American Vertical
Datum 1988 of the lowest floor (including basement)of all new or substantially improved
structures or (ii)the elevation to which new or substantially improved structures have been
floodproofed.
d.Notify adjacent communities(counties and the Department of Natural Resources prior to
any proposed alteration or relocation of a watercourse and submit evidence of such
notifications to the Federal Emergency Management Agency.
e.Keep a record of all permits,appeals and such other transactions and correspondence
pertaining to the administration of this Ordinance.
f.Submit to the Federal Insurance Administrator an annual report concerning the
community's participation,utilizing the annual report form supplied by the Federal
Insurance Administrator.
g.Notify the Federal Insurance Administration of any annexations or modifications to the
community's boundaries.
h.Review subdivision proposals to insure such proposals are consistent with the purpose of
this ordinance and advise the Planning and Zoning Commission and City Council of
potential conflict.
i.Maintain the accuracy of the community's Flood Insurance Rate Maps when;
1.Development placed within the Floodway (Overlay)District results in any of the
following:
a)An increase in the Base Flood Elevations,or
b)Alteration to the floodway boundary
2.Development place in Zones A,AE,AH,and AI-30 that does not include a
designated floodway that will cause a rise of more than one foot in the base
elevation;or
3.Development relocates or alters the channel.
Within 6 months of the completion of the development,the applicant shall submit to FEMA
all scientific and technical data necessary for a Letter of Map Revision.
j.Perform site inspections to ensure compliance with the standards of this Ordinance.
k.Forward all requests for Variances to the Board of Adjustment for consideration.Ensure all
requests include the information ordinarily submitted with applications as well as any
additional information deemed necessary to the Board of Adjustment.
B.Flood lain Develo ment Permit
1.Permit Required -A Floodplain Development Permit issued by the Administrative Official
shall be secured prior to any floodplain development (any man-made change to improved and
unimproved real estate,including but not limited to buildings or other structures,mining,
filling,grading,paving,excavation or drilling operations),including the placement of factory-
built homes.
2.Application for Permit -Application shall be made on forms furnished by the Administrative
Official and shall include the following:
a.Description of the work to be covered by the permit for which application is to be made.
b.Description of the land on which the proposed work is to be done (i.e.,lot,block,track,
street address or similar description)that will readily identify and locate the work to be
done.
c.Location and dimensions of all buildings and building additions
d.Indication of the use or occupancy for which the proposed work is intended.
e.Elevation of the base flood.
f.Elevation (in relation to North American Vertical Datum 1988 of the lowest floor
(including basement)of buildings or of the level to which a building is to be floodproofed.
g.For buildings being improved or rebuilt,the estimated cost of improvements and market
value of the building prior to the improvements.
h.Such other information as the Administrative Official deems reasonably necessary (e.g.,
drawings or a site plan)for the purpose of this Ordinance.
Action on Permit Application -The Administrative Official shall,within a reasonable time,
make a determination as to whether the proposed floodplain development meets the applicable
standards of this Ordinance and shall approve or disapprove the application.For disapprovals,
the applicant shall be informed,in writing,of the specific reasons therefore.The
Administrative Official shall not issue permits for variances except as directed by the Board of
Adjustment.
Construction and Use to be as Provided in Application and Plans -Floodplain Development
Permits based on the basis of approved plans and applications authorize only the use,
arrangement,and construction set forth in such approved plans and applications and no other
use,arrangement or construction.Any use,arrangement,or construction at variance with that
authorized shall be deemed a violation of this Ordinance.The applicant shall be required to
submit certification by a professional engineer or land surveyor,as appropriate,registered in
the State of Iowa,that the finished fill,building floor elevations,floodproofing,or other flood
protection measures were accomplished in compliance with the provisions of this Ordinance,
prior to the use or occupancy of any structure.
5306.5.Establishment of Zoning (Overlay)Districts
The floodplain areas within the jurisdiction of this ordinance are hereby divided into the following
districts:
Floodway (Overlay)District (FW)—those areas identified as Floodway on the Official Flood
Plain Zoning Map;
Floodway Fringe (Overlay)District (FF)—those areas identified as Zone AE on the Official
Flood Plain Zoning Map but excluding those areas identified as Floodway;
General Floodplain (Overlay)District (GF)—those areas identified as Zone A on the Official
Flood Plain Zoning Map,and;
The boundaries shall be as shown on the Official Floodplain Zoning Map.Within these districts,all
uses not allowed as Permitted Uses are prohibited unless a variance to the terms of this ordinance is
granted after due consideration by the Board of Adjustment.
5306.6.Floodway (Overlay)District (FW)
A.Permitted Uses
All uses within the Floodway District shall be permitted to the extent that they are not prohibited
by any other ordinance (or underlying zoning district)and provided they meet applicable
performance standards of the Floodway District.
B.Performance Standards
All Floodway District uses allowed as a Permitted shall meet the following standards.
1.No use shall be permitted in the Floodway District that would result in any increase in the base
flood elevation.Consideration of the effects of any development on flood levels shall be based
upon the assumption that an equal degree of development would be allowed for similarly
situated lands.
2.All uses within the Floodwa District shall:
a.Be consistent with the need to minimize flood damage.
b.Use construction methods and practices that will minimize flood damage.
c.Use consnuction materials and utility equipment that are resistant to flood damage.
3.No use shall affect the capacity or conveyance of the channel or floodway of any tributary to
the main stream,drainage ditch or any other drainage facility or system.
4.Structures,buildings and sanitary and utility systems,if permitted,shall meet the applicable
performance standards of the Floodway Fringe District and shall be constructed or aligned to
present the minimum possible resistance to flood flows.
5.Buildings,if permitted,shall have a low flood damage potential and shall not be for human
habitation.
6.Storage of materials or equipment that are buoyant,flammable,explosive or injurious to
human,animal or plant life is prohibited.Storage of other material may be allowed if readily
removable from the Floodway District within the time available after flood warning.
7.Watercourse alterations or relocations (channel changes and modifications)must be designed to
maintain the flood carrying capacity within the altered or relocated portion.In addition,such
alterations or relocations must be approved by the Department of Natural Resources.
8.Any fill allowed in the floodway must be shown to have some beneficial purpose and shall be
limited to the minimum amount necessary.
9.Pipeline river or stream crossings shall be buried in the streambed and banks or otherwise
sufficiently protected to prevent rupture due to channel degradation and meandering or due to
the action of flood flows.
5306.7.Floodway Fringe (Overlay)District FF
A.Permitted Uses
All uses within the Floodway Fringe District shall be permitted to the extent that they are not
prohibited by any other ordinance (or underlying zoning district)and provided they meet
applicable performance standards of the Floodway Fringe Disnict.
B.Performance Standards
All uses must be consistent with the need to minimize flood damage and meet the following
applicable performance standards.Where 100-year flood data has not been provided on the Flood
Insurance Rate Map,the Iowa Department of Natural Resources shall be contacted to compute
such data.The applicant will be responsible for providing the Department of Natural Resources
with sufficient technical information to make such determination.
1.All structures shall:
a.Be adequately anchored to prevent flotation,collapse or lateral movement of the structure.
b.Use construction methods and practices that will minimize flood damage.
c.Use construction materials and utility equipment that are resistant to flood damage.
2.Residential structures -All new or substantially improved residential structures shall have the
lowest floor,including basement,elevated a minimum of one (I)foot above the base flood
elevation.Construction shall be upon compacted fill which shall,at all points,be no lower than
1.0 fl.above the base flood elevation and extend at such elevation at least 18 feet beyond the
limits of any structure erected thereon.Alternate methods of elevating (such as piers or
extended foundations)may be allowed where existing topography,street grades,or other
factors preclude elevating by fill.In such cases,the methods used must be adequate to support
the structure as well as withstand the various forces and hazards associated with flooding.
All new residential structures located in areas that would become isolated due to flooding of
surrounding ground shall be provided with a means of access that will be passable by wheeled
vehicles during the base flood.However,this criterion shall not apply where the
Administrative Official determines there is sufficient flood warning time for the protection of
life and property.When estimating flood warning time,consideration shall be given to the
criteria listed in 567-75.2(3),iowa Administrative Code.
3.Non-residential structures -All new or substantially improved non-residential structures shall
have the lowest floor (including basement)elevated a minimum of one (1)foot above the base
flood elevation,or together with attendant utility and sanitary systems,be floodproofed to such
a level.When floodproofing is utilized,a professional engineer registered in the State of iowa
shall certify that the floodproofing methods used are adequate to withstand the flood depths,
pressures,velocities,impact and uplift forces and other factors associated with the base flood;
and that the structure,below the base flood elevation is watertight with walls substantially
impermeable to the passage of water.A record of the certification indicating the specific
elevation (in relation to North American Vertical Datum 1988 to which any structures are
floodproofed shall be maintained by the Administrator.
4.All new and substantiall im roved structures:
a.Fully enclosed areas below the "lowest floor"(not including basements)that are subject to
flooding shall be designed to automatically equalize hydrostatic flood forces on exterior
walls by allowing for the entry and exit of floodwaters.Designs for meeting this
requirement must either be certified by a registered professional engineer or meet or exceed
the following minimum criteria:
(1)A minimum of two (2)openings,with positioning on at least two (2)walls,
having a total net area of not less than one square inch for every square foot of
enclosed area subject to flooding shall be provided.
(2)The bottom of all openings shall be no higher than one foot above grade.
(3)Openings may be equipped with screens,louvers,valves,or other coverings or devices
provided they permit the automatic entry and exit of floodwaters.
Such areas shall be used solely for parking of vehicles,building access and low damage
potential storage.
b.New and substantially improved structures must be designed (or modified)and adequately
anchored to prevent flotation,collapse,or lateral movement of the structure resulting from
hydrodynamic and hydrostatic loads,including the effects of buoyancy.
c.New and substantially improved structures shall be constructed with electrical,heating,
ventilation,plumbing,air conditioning equipment and other service facilities elevated or
floodproofed to a minimum of one (1)foot above the base flood elevation).
5.Factor -built homes:
a.All factory-built homes,including those placed in existing factory-built home parks or
subdivisions,shall be elevated on a permanent foundation such that the lowest floor of the
structure is a minimum of one (I)foot above the 100-year flood level.
b.All factory-built homes,including those placed in existing factory-built home parks or
subdivisions,shall be anchored to resist flotation,collapse,or lateral movement.Methods
of anchoring may include,but are not limited to,use of over-the-top or frame ties to ground
anchors.Anchorage systems may include,but are not limited to,use of over-the-top or
frame ties to ground anchors as required by the State Building Code.
6.Utilit and Sanitar S stems:
a.On-site waste disposal and water supply systems shall be located or designed to avoid
impairment to the system or contamination from the system during flooding.
b.All new and replacement sanitary sewage systems shall be designed to minimize or
eliminate infiltration of flood waters into the system as well as the discharge of effluent into
flood waters.Wastewater treatment facilities (other than on-site systems)shall be provided
with a level of flood protection equal to or greater than one (I)foot above the 100-year
flood elevation.
c.New or replacement water supply systems shall be designed to minimize or eliminate
infiltration of flood waters into the system.Water supply treatment facilities (other than
on-site systems)shall be provided with a level of protection equal to or greater than one (I)
foot above the 100-year flood elevation.
d.Utilities such as gas or electrical systems shall be located and constructed to minimize or
eliminate flood damage to the system and the risk associated with such flood damaged or
impaired systems.
7.Stora e of materials and e ui ment that are flammable,explosive or injurious to human,
animal or plant life is prohibited unless elevated a minimum of one (I)foot above the base
flood elevation.Other material and equipment must either be similarly elevated or (i)not be
subject to major flood damage and be anchored to prevent movement due to flood waters or (ii)
be readily removable from the area within the time available after flood warning.
8.Flood control structural works such as levees,flood walls,etc.shall provide,at a minimum,
protection from the base flood with a minimum of three (3)fl.of design freeboard and shall
provide for adequate interior drainage.In addition,the Department of Natural Resources shall
approve structural flood control works.
9.Watercourse alterations or relocations must be designed to maintain the flood carrying capacity
within the altered or relocated portion.In addition,the Department of Natural Resources must
approve such alterations or relocations.
10.Subdivisions (including factory-built home parks and subdivisions)shall be consistent with the
need to minimize flood damages and shall have adequate drainage provided to reduce exposure
to flood damage.Development associated with subdivision proposals (including the
installation of public utilities)shall meet the applicable performance standards of this
Ordinance.Subdivision proposals intended for residential use shall provide all lots with a
means of access which will be passable by wheeled vehicles during the base flood.Proposals
for subdivisions greater than five (5)acres or My (50)lots (whichever is less)shall include
base flood elevation data for those areas located within the Floodplain (Overlay)District.
11.Accessor Structures to Residential Uses
a.Detached garages,sheds,and similar structures that are incidental to a residential use are
exempt from the base flood elevation requirements where the following criteria are
satisfied.
(1)The structure shall be designed to have low flood damage potential.Its size shall not
exceed 600 sq.ft.in size.Those portions of the structure located less than I foot
above the BFE must be constructed of flood-resistant materials.
(2)The structure shall be used solely for low flood damage potential purposes such as
vehicle parking and limited storage.The structure shall not be used for human
habitation.
(3)The structure shall be constructed and placed on the building site so as to offer
minimum resistance to the flow of floodwaters.
(4)The structure shall be firmly anchored to resist flotation,collapse and lateral
movement.
(5)The structure's service facilities such as electrical and heating equipment shall be
elevated or floodproofed to at least one foot above the base flood elevation.
(6)The structure's walls shall include openings that satisfy the provisions of Section
306.7 (B)4a of this Ordinance.
b.Exemption from the 100-year flood elevation requirements for such a structure may result
in increased premium rates for flood insurance coverage of the structure and its contents.
12.Recreational Vehicles
a.Recreational vehicles are exempt from the requirements of Section 306.7 (B)5 of this
Ordinance regarding anchoring and elevation of factory-built homes when the following
criteria are satisfied.
(1)The recreational vehicle shall be located on the site for less than 180 consecutive days,
and,
(2)The recreational vehicle must be fully licensed and ready for highway use.A
recreational vehicle is ready for highway use if it is on its wheels or jacking system
and is attached to the site only by quick disconnect type utilities and security devices
and has no permanently attached additions.
b.Recreational vehicles that are located on the site for more than 180 consecutive days or are
not ready for highway use must satisfy requirements of Section 306.7(B)5 of this Ordinance
regarding anchoring and elevation of factory-built homes.
13.Pi eline river and stream crossin s shall be buried in the streambed and banks,or otherwise
sufficiently protected to prevent rupture due to channel degradation and meandering.
14.Maximum Dama e Potential Uses —All new or substantially improved maximum damage
potential uses shall have the lowest floor (including basement)elevated a minimum of one (1)
foot above the elevation of the 500-year flood,or together with attendant utility and sanitary
systems,be floodproofed to such a level.When floodproofing is utilized,a professional
engineer registered in the State of Iowa shall certify that the floodproofing methods used are
adequate to withstand the flood depths,pressures,velocities,impact and uplifl forces and other
factors associated with the 0.2'lo annual chance flood;and that the structure,below the 0.2'/o
annual chance flood elevation is watertight with walls substantially impermeable to the passage
of water.A record of the certification indicating the specific elevation (in relation to North
American Vertical Datum 1988 to which any structures are floodproofed shall be maintained
by the Administrator.Where 0.2'lo chance flood elevation data has not been provided in the
Flood Insurance Study,the Iowa Department of Natural Resources shall be contacted to
compute such data.The applicant will be responsible for providing the Department of Natural
Resources with sufficient technical information to make such determinations.
$306.8.General Floodplain (Overlay)District FP
A.Permitted Uses
l.All uses within the General Floodplain District shall be permitted to the extent that they are
not prohibited by any other ordinance (or underlying zoning district)and provided they meet the
applicable performance standards of the General Floodplain District.
2.Any uses which involve placement of structures,factory-built homes,fill or other obstructions,
storage of materials or equipment,excavation or alteration of a watercourse shall be reviewed by
the Department of Natural Resources to determine (i)whether the land involved is either wholly or
partly within the floodway or floodway fringe and (ii)the base flood elevation.The applicant shall
be responsible for providing the Department of Natural Resources with sufficient technical
information to make the determination.
3.Review by the Iowa Department of Natural Resources is not required for the proposed
construction of new or replacement bridges or culverts where:
a.The bridge or culvert is located on a stream that drains less than one hundred (100)square
miles,and
b.The bridge or culvert is not associated with a channel modification that constitutes a
channel change as specified in 567-71.2(I)b,Iowa Administrative Code.
B.Performance Standards
All uses,or portions thereof,to be located in the floodway as determined by the Department of
Natural Resources shall meet the applicable provisions and standards of the Floodway
(Overlay)District Section 306.7.
All uses,or portions thereof,to be located in the floodway fringe as determined by the
Department of Natural Resources shall meet the applicable provisions and standards of the
Floodway Fringe (Overlay)District Section 306.7
5306.9.Appointment and Duties of Board of Adjustment
A.Appointment and Duties of Board of Adjustment —A Board of Adjustment is hereby
established which shall hear and decide (i)appeals and (ii)requests for variances to the
provisions of this ordinance,and shall take any other action which is required of the Board.
B.Appeals -Where it is alleged there is any error in any order,requirement,decision,or
determination made by an administrative official in the enforcement of this ordinance,the
aggrieved party may appeal such action.The notice of appeal shall be filed with the Board of
Adjustment and with the official from whom the appeal is taken and shall set forth the specific
reason for the appeal.The official from whom the appeal is taken shall transmit to the Board of
Adjustment all the documents constituting the record upon which the action appealed from was
taken.
C.Variance -The Board of Adjustment may authorize upon request in specific cases such
variances from the terms of this Ordinance that will not be contrary to the public interest where,
owing to special conditions,a literal enforcement of the provisions of this Ordinance will result
in unnecessary hardship.Variances granted must meet the following applicable standards.
1.Variances shall only be granted 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 deterinination that the granting of the variance will not result in
increased flood heights,additional threats to public safety,extraordinary public expense,
create nuisances,cause fraud on or victimization of the public or conflict with existing local
codes or ordinances.
2.Variances shall not be issued within any designated floodway if any increase in flood levels
during the 100-year flood would result.Consideration of the effects of any development on
flood levels shall be based upon the assumption that an equal degree of development would
be allowed for similarly situated lands.
3.Variances shall only be granted upon a determination that the variance is the minimum
necessary,considering the flood hazard,to afford relief.
4.In cases where the variance involves a lower level of flood protection for buildings than
what is ordinarily required by this Ordinance,the applicant shall be notified in writing over
the signature of the Administrator that:(i)the issuance of a variance will result in increased
premium rates for flood insurance up to amounts as high as $25 for $100 of insurance
coverage and (ii)such construction increases risks to life and property.
5.All variances granted shall have the concurrence or approval of the Department of Natural
Resources.
D.Hearings and Decisions of the Board of Adjustment
1.Hearings.Upon the filing with the Board of Adjustment of an Appeal or a request for a
Variance,the Board shall hold a public hearing.The Board shall fix a reasonable time for
the hearing and give public notice thereof,as well as due notice to parties in interest.At the
hearing,any party may appear in person or by agent or attorney and present written or oral
evidence.The board may require the appellant or applicant to provide such information as
is reasonably deemed necessary and may request the technical assistance and/or evaluation
of a professional engineer or other expert person or agency,including the Department of
Natural Resources.
2.Decisions.The Board shall arrive at a decision on an Appeal or Variance within a
reasonable time.In passing upon an Appeal,the Board may,so long as such action is in
conformity with the provisions of this ordinance,reverse or affirm,wholly or in part,or
modify the order,requirement,decision,or determination appealed from,and it shall make
its decision in writin settin forth the findin s of fact and the reasons for its decision.In
granting a Variance,the board shall consider such factors as contained in this section and
all other relevant sections of this ordinance and may prescribe such conditions as contained
in Section 306.9 (D)2 (B).
A.Factors Upon Which the Decision of the Board of Adjustment Shall be Based.In
passing upon applications for Variances,the Board shall consider all relevant factors
specified in other sections of this Ordinance and:
1.The danger to life and property due to increased flood heights or velocities
caused by encroachments.
2.The danger that materials may be swept on to other land or downstream to the
injury of others.
3.The proposed water supply and sanitation systems and the ability of these
systems to prevent disease,contamination and unsanitary conditions.
4.The susceptibility of the proposed facility and its contents to flood damage and
the effect of such damage on the individual owner.
The importance of the services provided by the proposed facility to the City.
The requirements of the facility for a floodplain location.
The availability of alternative locations not subject to flooding for the proposed
use.
The compatibility of the proposed use with existing development and
development anticipated in the foreseeable future.
The relationship of the proposed use to the comprehensive plan and floodplain
management program for the area.
I O.The safety of access to the property in times of flood for ordinary and emergency
vehicles.
The expected heights,velocity,duration,rate of rise and sediment transport of the
flood water expected at the site.
12.The cost of providing governmental services during and after flood conditions,
including maintenance and repair of public utilities (sewer,gas,electrical and
water systems),facilities,streets and bridges.
13.Such other factors which are relevant to the purpose of this Ordinance.
B Conditions Attached to Variances -Upon consideration of the factors listed above,the
Board of Adjustment may attach such conditions to the granting of variances as it
deems necessary to further the purpose of this Ordinance.Such conditions may
include,but not necessarily be limited to:
Modification of waste disposal and water supply facilities.
Limitation of periods of use and operation.
Imposition of operational controls,sureties,and deed restrictions.
Requirements for construction of channel modifications,dikes,levees,and other
protective measures,provided such are approved by the Department of Natural
Resources and are deemed the only practical alternative to achieving the purpose
of this Ordinance.
Floodproofing measures shall be designed consistent with the flood protection
elevation for the particular area,flood velocities,duration,rate of rise,
hydrostatic and hydrodynamic forces,and other factors associated with the
regulatory flood.The Board of Adjustment shall 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
elevation and associated flood factors for the particular area.
E.Appeals to the Court -Any person or persons,jointly or severally,aggrieved by any decision
of the (BOARD OF APPEALS)may present to a court of record a petition,duly verified,
setting forth that such decision is illegal,in whole or in part,specifying the grounds of the
illegality.Such petition shall be presented to the court within thirty days after the filing of
the decision in the office of the Board.
$306.10.Nonconforming Uses
A.A structure or the use of a structure or premises which was lawful before the passage or
amendment of this Ordinance,but which is not in conformity with the provisions of this Ordinance,
may be continued subject to the following conditions:
l.If such use is discontinued for six (6)consecutive months,any future use of the building
premises shall conform to this Ordinance.
2.Uses or adjuncts thereof that are or become nuisances shall not be entitled to continue as
nonconforming uses.
3.If any nonconforming use or structure is destroyed by any means,including flood,it shall not
be reconstructed if the cost is more than fifty (50)percent of the market value of the structure
before the damage occurred,unless it is reconstructed in conformity with the provisions of this
Ordinance.
B.Except as provided in Section 306.10 A 2 any use which has been permitted as a Variance shall
be considered a conforming use
5306.11.Penalties for Violation
Violations of the provisions of this Ordinance or failure to comply with any of the requirements
(including violations of conditions and safeguards established in connection with grants of Variances)
shall constitute a misdemeanor.Any person who violates this Ordinance or fails to comply with any of
its requirements shall upon conviction thereof be fined not more than $500.00 (five hundred dollars)or
imprisoned for not more than thirty (30)days.Each day such violation continues shall be considered a
separate offense.Nothing herein contained shall prevent the City of Waukee from taking such other
lawful action as is necessary to prevent or remedy violation.
5306.12.Amendments
The regulations and standards set forth in this Ordinance may from time to time be amended,
supplemented,changed,or repealed.No amendment,supplement,change,or modification shall be
undertaken without prior approval of the Department of Natural Resources.
Section 2.~Re ealer.All ordinances or parts of ordinances in conflict with the provisions
of this ordinance are hereby repealed.
Section 3.Severabilit Clause.If any section,provision or part of this ordinance shall be
adjudged invalid or unconstitutional,such adjudication shall not affect the validity of the ordinance as
a whole or any section,provision,or part thereof not adjudged invalid or unconstitutional.
Section 4.Effective Date.This ordinance shall be in effect upon its final passage,approval
and publication as provided by law.
Passed by the Council this 5'"day of November,2018,and approved this 5'"day of November,2018.
Attest:
e d,yoi'
Rebecca D.Schuett,City Clerk