HomeMy WebLinkAboutORDINANCE - 2785 - 10/24/2000 - FLOOD HAZARD AREAS, SPECIAL (Rescinding Ord. 2219)ORDINANCE NO. 2785
AN ORDINANCE ADOPTING REGULATIONS FOR DEVELOPMENT IN SPECIAL
FLOOD HAZARD AREAS AND RESCINDING ORDINANCE NO. 2219 WHICH
ESTABLISHED AND AMENDED THE FLOODPLAIN REGULATIONS OF THE
VILLAGE OF ELK GROVE VILLAGE
NOW, THEREFORE, BE IT ORDAINED by the President and Board of Trustees
of the Village of Elk Grove Village, Cook and DuPage Counties, Illinois:
Section 1: That Ordinance No. 2219, Regulations for Development in
Special Flood Hazard Areas, duly passed and approved by the President and
Board of Trustees on March 10, 1992 is hereby repealed:
Section 2: That Regulations for Development in Special Flood Hazard
Areas of the Village of Elk Grove Village be adopted as follows:
SECTION
8-11- 1:
PURPOSE
8-11- 2:
DEFINITIONS
8-11- 3:
HOW TO USE THIS ORDINANCE
8-11- 4:
DUTIES OF THE ENFORCEMENT OFFICIAL
8-11- 5:
BASE FLOOD ELEVATION
8-11- 6:
OCCUPATION AND USE OF FLOOD FRINGE AREAS
8-11- 7:
OCCUPATION AND USE OF DESIGNATED FLOODWAYS
8-11- 8:
OCCUPATION AND USE OF SPECIAL FLOOD HAZARD AREA
WHERE FLOODWAYS ARE NOT IDENTIFIED
8-11- 9:
PERMITTING REQUIREMENTS APPLICABLE TO ALL FLOOD
PLAIN AREAS AND PROTECTION OF BUILDING
8-11-10:
OTHER DEVELOPMENT REQUIREMENTS
8-11-11:
VARIANCES
8-11-12:
DISCLAIMER OF LIABILITY
8-11-13:
PENALTY
8-11-14:
ABROGATION AND GREATER RESTRICTIONS
8-11-15:
SEPARABILITY
8-11-16:
EFFECTIVE DATE
PURPOSE: This Ordinance is enacted pursuant to the police powers
granted to the Village of Elk Grove Village by 65 ILLS 5/1-2-1, 5/11-12-12,
5/11-30-2, 5/11-30-8, and 5/11-31-2 (1994). The purpose of this Ordinance
is to maintain Elk Grove Village's eligibility in the National Flood
Insurance Program; to minimize potential losses due to periodic, flooding
including loss of life, loss of 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
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welfare; and to preserve and enhance the quality of surface waters,
conserve economic and natural value and provide for the wise utilization of
water and related land resources. This Ordinance is adopted in order to
accomplish the following specific purposes:
A. To meet the requirements of 615 ILCS 5/18g Rivers, Lakes and
Streams Act.
B. To assure that new development does not increase the flood or drainage
hazards to others, or create conditions susceptible to erosion;
C. To protect new buildings and major improvements to buildings from flood
damage;
D. To protect human life and health from the hazards of flooding;
E. To lessen the burden on the taxpayer for flood control projects,
repairs to flood -damaged public facilities and utilities, and flood
rescue and relief operations; and
F. To make federally subsidized flood insurance available for property in
the Village by fulfilling the requirements of the National Flood
Insurance Program.
G. To comply with the rules and regulations of the National Flood
Insurance Program codified as 44 CFR 59-79, as amended.
H. To protect, conserve, and promote the orderly development of land and
water resources;
I. To preserve the natural characteristics and function of watercourses
and floodplains in order to moderate flood and stormwater impacts,
improve water quality, reduce soil erosion, protect aquatic and
riparian habitat, provide recreational opportunities, provide aesthetic
benefits and enhance community and economic development.
8-11-2:
DEFINITIONS: For the purposes of this Ordinance, the following
definitions are adopted:
ACT: "An act in relation to the regulation of the rivers, lakes and streams
of the State of Illinois", 615 ILLS 5/5 et seq.
APPLICANT: Any person, firm, corporation or agency which submits an
application.
APPROPRIATE USE: Only uses of the designated floodway that are permissible
and will be considered for permit issuance. The only uses that will be
allowed are as specified in subsection 8-11-7B of this chapter.
BASE FLOOD: The flood having a one -percent probability of being equaled or
exceeded in any given year. The base flood is also known as the 100 -year
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frequency flood event. Application of base flood elevation at any location
is as defined in Section 8-11-5 of this chapter.
BUILDING: A structure that is principally above ground and is enclosed by
walls and a roof. The term includes a gas or liquid storage tank, a
manufactured home, mobile home or a prefabricated building. This term also
includes recreational vehicles and travel trailers to be installed on a
site for more than 180 days unless fully licensed and ready for highway
use.
CHANNEL: Any river, stream, creek, brook, branch, natural or artificial
depression, ponded area, flowage, slough, ditch, conduit, culvert, gully,
ravine, wash, or natural or man-made drainageway, which has a definite bed
and banks or shoreline, in or into which surface or groundwater flows,
either perennially or intermittently.
CHANNEL MODIFICATION: Alteration of a channel by changing the physical
dimensions or materials of its bed or banks. Channel modification includes
damming, rip -rapping or other armoring, widening, deepening, straightening,
relocating, lining and significant removal of native vegetation from the
bottom or banks. Channel modification does not include the clearing of dead
or dying vegetation, debris, or trash from the channel. Channelization is
a severe form of channel modification involving a significant change in the
channel cross-section and typically involving relocation of the existing
channel (e.g.straightening).
COMPENSATORY STORAGE: An artificially excavated, hydraulically equivalent
volume of storage within the SFHA used to balance the loss of natural flood
storage capacity when artificial fill or structures are placed within the
flood plain. The uncompensated loss of natural flood plain storage can
increase off-site floodwater elevations and flows.
CONDITIONAL APPROVAL OF A DESIGNATED FLOODWAY MAP CHANGE: Pre -construction
approval by IDNR/OWR and the Federal Emergency Management Agency of a
proposed change to the floodway map. This pre -construction approval,
pursuant to this part, gives assurances to the property owner that once an
Appropriate Use is constructed according to permitted plans; the floodway
map can be changed, as previously agreed, upon review and acceptance of as -
built plans.
CONDITIONAL LETTER OF MAP REVISION (CLOMR): A letter which indicates that
the Federal Emergency Management Agency will revise base flood elevations,
flood insurance rate zones, flood boundaries or floodway as shown on an
effective Flood Hazard Boundary Map or Flood Insurance Rate Map, once the
as -built plats are submitted and approved.
CONTROL STRUCTURE: A structure designed to control the rate of flow that
passes through the structure, given a specific upstream and downstream
water surface elevation.
DAM: All obstructions, wall embankments or barriers, together with their
abutments and appurtenant works, if any, constructed for the purpose of
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storing or diverting water or creating a pool. Underground water storage
tanks are not included.
DESIGNATED FLOODWAY: The channel, including on -stream lakes, and that
portion of the floodplain adjacent to a stream or watercourse as designated
by IDNR/OWR, which is needed to store and convey the existing 100 -year
frequency flood discharge with no more than a 0.1 foot increase in stage
due to the loss of flood conveyance or storage, and no more than a 10
percent increase in velocities.
A. The floodways are designated for Salt Creek, the Elk Grove
Boulevard Drainage Ditch, the Unnamed Creek, the West Branch of
Salt Creek and the Tributary to the West Branch of Salt Creek on
the following map number 01731C and panels 0189F, 0193F, 0194F,
0211F, 0213F, 0214F, 0218F, 0330F, 0331F, 0332F, 0351F dated
November 6, 2000 respectively, of the countywide Flood Insurance
Rate Map for Cook County prepared by the Federal Emergency
Management Agency. The floodways within the Village limits in
DuPage County are designated on the Flood Boundary & Floodway
Map for DuPage County prepared by FEMA and dated 10/18/88 and on
the Regulatory Floodplain Map prepared by IDNR/OWR and dated
7/1/79. When two floodway maps exist for a waterway, the more
restrictive floodway limits shall prevail.
B. The floodways for those parts of unincorporated Cook and DuPage
Counties that are within the one and half mile extraterritorial
jurisdiction of the Village of Elk Grove Village and may be
annexed into the Village are designated for tributary to Salt
Creek within Cook County on the following map number 01731C and
panels 0192F and 0352F dated November 6, 2000, respectively, of
the countywide Flood Insurance Rate Map for Cook County prepared
by the Federal Emergency Management Agency and for Salt Creek
within DuPage County on the Flood Boundary & Floodway Map
prepared by FEMA and dated 10/18/88 and on the Regulatory
Floodplain Map prepared by IDNR/OWR and dated 7/1/79. When two
floodways exist for a waterway, the more restrictive floodway
limit shall prevail.
C. To locate the designated floodway boundary on any site, the
designated floodway boundary should be scaled off the designated
floodway map and located on a site plan, using reference marks
common to both maps. Where interpretation is needed to
determine the exact location of the designated floodway
boundary, IDNR/OWR should be contacted for the interpretation.
DEVELOPMENT: Any man-made change to real estate, including:
A. Construction, reconstruction, repair, or placement of a
building or any addition to a building.
B. Installing a manufactured home on a site, preparing a site for
a manufactured home, or installing a travel trailer on a site
for more than 180 days. If the travel trailer or recreational
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vehicle is on site for less than 180 days, it must be fully
licensed and ready for highway use.
C. Drilling, mining, installing utilities, construction of roads,
bridges, or similar projects.
D. Demolition of a structure or redevelopment of a site.
E. Clearing of land as an adjunct of construction.
F. Construction or erection of levees, walls, fences, dams, or
culverts; channel modifications; filling, dredging, grading,
excavating, paving, or other non-agricultural alterations of
the ground surface; storage of materials; deposit or solid or
liquid waste;
G. Any other activity of man that might change the direction,
height, or velocity of flood or surface water, including
extensive vegetation removal;
Development does not include maintenance of existing buildings
and facilities such as re -roofing or re -surfacing of roads when
there is no increase in elevation, or gardening, plowing, and
similar agricultural practices that do not involve filling,
grading, or construction of levees.
ELEVATION CERTIFICATES: A form published by the Federal Emergency
Management Agency that is used to certify the elevation to which a building
has been elevated.
EROSION: The general process whereby soils are moved by flowing water or
wave action.
EXEMPT ORGANIZATIONS: Organizations which are exempt from this Ordinance
per the Illinois Compiled statutes (ILCS) including State, Federal or local
units of government.
EXISTING MANUFACTURED HOME PARK OR SUBDIVISION: A manufactured home park or
subdivision for which the construction of facilities for servicing the lots
on which the manufactured 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) has been completed
before April 1, 1990.
EXPANSION TO AN EXISTING MANUFACTURED HOME PARK OR SUBDIVISION: The
preparation of additional sites by the construction of facilities for
servicing the lots on which the manufactured homes are to be affixed
(including the installation of utilities, the construction of streets, and
either final site grading or the pouring of concrete pads).
FEMA: Federal Emergency Management Agency and its regulations at 44CFR 59-
79 effective as of September 29, 1989. This incorporation does not include
any later editions or amendments.
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FLOOD: A general and temporary condition of partial or complete inundation
of normally dry land areas from overflow of inland or tidal waves, or the
unusual and rapid accumulation or runoff of surface waters from any source.
FLOOD FREQUENCY: A period of years, based on a statistical analysis, during
which a flood of a stated magnitude may be expected to be equaled or
exceeded.
FLOOD FRINGE: That portion of the flood plain outside of the designated
floodway.
FLOOD INSURANCE RATE MAPS (FIRM): A map prepared by the Federal
Emergency Management Agency that depicts the special flood hazard area
(SFHA) within a community. This map includes insurance rate zones and
floodplains and may or may not depict floodways.
FLOODPLAIN: That land typically adjacent to a body of water with ground
surface elevations at or below the base flood or the 100 -year frequency
flood elevation. Floodplains may also include detached Special Flood
Hazard Areas, ponding areas, etc. The floodplain is also known as the
Special Flood Hazard Area (SFHA).
A. The floodplains are those lands within the jurisdiction of the
Village of Elk Grove Village that are subject to inundation by
the base flood or 100 -year frequency flood. The SFHA's of the
Village are generally identified as such on the following map
number 01731C and panels 0189F, 0193F, 0194F, 0211F, 0213F,
0214F, 0218F, 0331F, 0332F, 0351F dated November 6, 2000,
respectively, of the countywide Flood Insurance Rate Map for
Cook County and on the FIRM for DuPage County dated 10/18/88
prepared by the Federal Emergency Management Agency.
B. The SFHA's for those parts of unincorporated Cook County that
are within the one and half mile extraterritorial jurisdiction
of the Village and may be annexed into the village are
designated for tributary to Salt Creek on the following map
number 17031C and panels 0192F, 0352F dated November 6, 2000,
respectively, of the countywide Flood Insurance Rate Map for
Cook County and on the FIRM for DuPage County dated 10/18/88
prepared by the Federal Emergency Management Agency.
FLOODPROOFING: Any combination of structural and non-structural additions,
changes or adjustments to structures which reduce or eliminate flood damage
to real estate or improved real property, water and sanitary facilities,
structures and their contents.
FLOODPROOFING CERTIFICATE: A form published by the Federal Emergency
Management Agency that is used to certify that a building has been designed
and constructed to be structurally dry floodproofed to the flood protection
elevation.
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FLOOD PROTECTION ELEVATION (FPE): The elevation of the base flood or 100
year frequency flood plus one foot of freeboard at any given location in
the SFHA.
FREEBOARD: An increment of elevation added to the base flood elevation to
provide a factor of safety for uncertainties in calculations, future
watershed developments, unknown localized conditions, wave actions and
unpredictable effects such as those caused by ice or debris jams.
HISTORIC STRUCTURE" - Any structure that is:
A. Listed individually in the National Register of Historic Places
or preliminary determined by the Secretary of the Interior as
meeting the requirements for individual listing on the National
Register;
B. Certified or preliminary determined by the Secretary of the
Interior as contributing to the historic district or a district
preliminary determined by the Secretary to qualify as a
registered historic district;
C. Individually listed on the State inventory of historic places by
the Illinois Historic Preservation Agency;
D. Individually listed on a local inventory of historic places that
has been certified by the Illinois Historic Preservation Agency.
HYDROLOGIC AND HYDRAULIC CALCULATIONS: Engineering analysis which determine
expected flood flows and flood elevations based on land characteristics and
rainfall events.
IDNR/OWR: Illinois Department of Natural Resources, Office of Water
Resources.
LETTER OF MAP AMENDMENT (LOMA): Official determination by FEMA that a
specific structure is not in a 100 -year flood zone; amends the effective
Flood Hazard Boundary Map, FHBM or FIRM.
LETTER OF MAP REVISION (LOMR): Letter that revises base flood or 100 -year
frequency flood elevations, flood insurance rate zones, flood boundaries or
floodways as shown on an effective FHBM or FIRM.
MANUFACTURED HOME: A structure, transportable in one or more sections,
which is built on a permanent chassis and is designated for use with or
without a permanent foundation when attached to the required utilities.
The term manufactured homes also includes park trailers, travel trailers
and other similar vehicles placed on site for more than 160 consecutive
days. The term "manufactured home" does not include a "recreational
vehicle".
MANUFACTURED HOME PARK OR SUBDIVISION: A parcel(or contiguous parcels) of
land divided into two or more manufactured home lots for rent or sale.
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MITIGATION: Mitigation includes those measures necessary to minimize the
negative effects which floodplain development activities might have on the
public health, safety and welfare. Examples of mitigation include
compensatory storage, soil erosion and sedimentation control, and channel
restoration. Mitigation may also include those activities taken to reduce
a structure's susceptibility to flooding.
NEW MANUFACTURED HOME PARK OR SUBDIVISION: Manufactured home park or
subdivision for which the construction of facilities for servicing the lots
on which the manufactured 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) has been completed on
or after April 1, 1990.
NGVD: National Geodetic Vertical Datum of 1929. Reference surface set by
the National Geodetic Survey deduced from a continental adjustment of all
existing adjustments in 1929.
NATURAL: When used in reference to channels means those channels formed by
the existing surface topography of the earth prior to changes made by man.
A natural stream tends to follow a meandering path; its floodplain is not
constrained by levees; the area near the bank has not been cleared, mowed
or cultivated; the stream flows over soil and geologic materials typical of
the area with no substantial alteration of the course or cross-section of
the stream caused by filling or excavating. A modified channel may regain
some natural characteristics over time as the channel meanders and
vegetation is re-established. Similarly, a modified channel may be
restored to more natural conditions by man through regrading
and revegetation.
ORDINARY HIGH WATER MARK (OHWM): The point on the bank or shore up to which
the presence and action of surface water is so continuous so as to leave a
distinctive mark such as by erosion, destruction or prevention of
terrestrial vegetation, predominance of aquatic vegetation or other easily
recognized characteristics.
PUBLIC FLOOD CONTROL PROJECT: A flood control project which will be
operated and maintained by a public agency to reduce flood damages to
existing buildings and structures which includes a hydrologic and hydraulic
study of the existing and proposed conditions of the watershed. Nothing in
this definition shall preclude the design, engineering, construction or
financing, in whole or in part, of a flood control project by persons or
parties who are not public agencies.
PUBLIC BODIES OF WATERS: All open public streams and lakes capable of being
navigated by watercraft, in whole or in part, for commercial uses and
purposes, and all lakes, rivers, and streams which in their natural
condition were capable of being improved and made navigable, or that are
connected with or discharge their waters into navigable lakes or rivers
within, or upon the borders of the State of Illinois, together with all
bayous, sloughs, backwaters, and submerged lands that are open to the main
channel or body of water directly accessible thereto.
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RECREATIONAL VEHICLE OR TRAVEL TRAILER: A vehicle which is:
A. Built on a single chassis;
B. 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.
REGISTERED LAND SURVEYOR: A land surveyor registered in the State of
Illinois, under the Illinois Land Surveyors Act (225 ILCS 330/1, et seq.).
REGISTERED PROFESSIONAL ENGINEER: An engineer registered in the State of
Illinois, under The Illinois Professional Engineering Practice Act (225
ILCS 325/1, et seq.).
REPAIR, REMODELING OR MAINTENANCE: Development activities which do not
result in any increases in the outside dimensions of a building or any
changes to the dimensions of a structure.
RETENTION/DETENTION FACILITY: A retention facility stores stormwater runoff
without a gravity release. A detention facility provides for storage of
stormwater runoff and controlled release of this runoff during and after a
floor or storm.
RIVERINE SFHA: Any SFHA subject to flooding from a river, creek,
intermittent stream, ditch, or stream lake system or any other identified
channel. This term does not include areas subject to flooding from lakes,
ponding areas, areas of sheet flow, or other areas not subject to overbank
flooding.
RUNOFF: The water derived from melting snow or rain falling on the land
surface, flowing over the ground or collected in channels or conduits.
SEDIMENTATION: The processes that deposit soils, debris, and other
materials either on other ground surfaces or in bodies of water or
watercourses.
SPECIAL FLOOD HAZARD AREA (SFHA): Any base flood area subject to flooding
from a river, creek, intermittent stream, ditch, or any other identified
channel or ponding and shown on a Flood Hazard
Boundary Map or Flood Insurance Rate Map as Zone A, AO, Al -30, AE, A99, AH,
VO, V30, VE, V, M, E, D, or X.
STRUCTURE: The results of a man-made change to the land constructed on or
below the ground, including the construction, reconstruction or placement
of a building or any addition to a building; installing a manufactured home
on a site; preparing a site for a manufactured home or installing a travel
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trailer on a site for more than 180 days unless they are fully licensed and
ready for highway use.
SUBSTANTIAL DAMAGE: A building is considered substantially damaged when it
sustains damage from any cause (fire, flood, earthquake, etc.) whereby the
cost of fully restoring the structure would equal or exceed 50 percent of
the pre -damage market value of the structure, regardless of the actual
repair work performed.
SUBSTANTIAL IMPROVEMENT
A. 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.
B. 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.
C. 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 "historic structure", provided that the
alteration will not preclude the structure's continued
designation as a historic structure.
TRANSITION SECTION: Reaches of the stream or floodway where water flows
from a narrow cross-section to a wide cross-section or vice versa.
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HOW TO USE THIS ORDINANCE: The Director of Engineering and Community
Development shall be responsible for fulfilling all of the duties listed in
Section 8-11-4 of this chapter.
To fulfill those duties, the Director of Engineering and Community
Development first shall use criteria listed in Section 8-11-5, "Base Flood
Elevations", to determine whether the development site is located within a
floodplain.
Once it has been determined that a site is located within a floodplain, the
Director of Engineering and Community Development must determine whether
the development site is within a flood fringe, a designated floodway, or
within a SFHA or floodplain for which no floodway has been identified.
If the site is within a flood fringe, the Director of Engineering and
Community Development shall require that the minimum requirements of
Section 8-11-6 of this chapter be met.
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If the site is within a floodway, the Director of Engineering and Community
Development shall require that the minimum requirements of Section 8-11-7
be met.
If the site is located within a SFHA or floodplain for which no detailed
study has been completed and approved, the Director of Engineering and
Community Development shall require that the minimum requirements of
Section 8-11-8 be met.
In addition, the general requirements of Section e-11-9 shall be met for
all developments meeting the requirements of Section 8-11-6, 8-11-7, or 8-
11-8.
The Director of Engineering and Community Development shall assure that all
subdivision proposals shall meet the requirements of Section 8-11-10.
If a variance is to be granted for a proposal, the Director of Engineering
and Community Development shall review the requirements of Section 8-11-11
to make sure they are met. In addition, the Director of Engineering and
Community Development shall complete all notification requirements.
In order to assure that property owners obtain permits as required in this
Ordinance, the Director of Engineering and Community Development may take
any and all actions as outlined in Section 8-11-13.
8-11-4:
DUTIES OF THE ENFORCEMENT OFFICIAL(S): The Director of Engineering and
Community Development shall be responsible for the general administration
and enforcement of this Ordinance which shall include the following:
A. DETERMINING THE FLOODPLAIN DESIGNATION:
1. Check all new development sites to determine whether they are
in a Special Flood Hazard Area (SFHA).
2. If they are in a SFHA, determine whether they are in a
floodway, flood fringe or in a floodplain on which a detailed
study has not been conducted and which drains more than one (1)
square mile.
3. Check whether the development is potentially within an extended
SFHA (with a drainage area less than one square mile),
indicating that the development would have adverse impacts
regarding storage, conveyance, or inundation which would be the
basis for the applicant being required to delineate the
floodplain and floodway and be subject to the remaining
Sections of this Ordinance.
B. PROFESSIONAL ENGINEER REVIEW:
1. If the development site is within a floodway or in a floodplain
on which a detailed study has not been conducted and which
drains more than one (1) square mile then the permit shall be
referred to a registered professional engineer (P.E.) under the
employ or contract of the Village for review to ensure that the
development meets the requirements of Section 8-11-7 of this
chapter.
2. In the case of an Appropriate Use, the P.E. shall state in
writing that the development meets the requirements of said
Section 8-11-7.
C. DAM SAFETY REQUIREMENTS:
1. Ensure that an IDNR/OWR permit has been issued or a letter
indicating no permit is required, if the proposed
development activity includes construction of a dam as defined
in Section 8-11-2 "dam".
2. Regulated dams may include weirs, restrictive culverts or
impoundment structures.
D. OTHER PERMIT REQUIREMENTS:
Ensure that any and all required federal, state and local permits
are received prior to the issuance of a floodplain development
permit.
E. PLAN REVIEW AND PERMIT ISSUANCE:
1. Ensure that all development activities within the SFHA's of the
jurisdiction of the Village of Elk grove Village meet the
requirements of this chapter.
2. Issue a floodplain development permit in accordance with the
provisions of this Ordinance and other regulations of this
community when the development meets the conditions of this
chapter.
F. INSPECTION REVIEW:
Inspect all development projects before, during and after
construction to assure proper elevation of the structure and to
ensure compliance with the provisions of this chapter.
G. ELEVATION AND FLOODPROOFING CERTIFICATES:
Maintain permit files including:
1. An Elevation certificate certifying the elevation of the lowest
floor (including basement) of a residential or non-residential
building subject to Section 8-11-9 of this chapter for public
inspection and provide copies of the same.
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2. The elevation to which a non-residential building has been
floodproofed, using a Floodproofing Certificate, for all
buildings subject to Section 8-11-9 of this chapter.
H. RECORDS FOR PUBLIC INSPECTION:
Maintain for public inspection and furnish upon request base flood
data, SFHA and regulatory floodway maps, copies of federal or
state permit documents, variance documentation, Conditional Letter
of Map Revision, Letter of Map Revision, Letter of Map Amendment
and "as built" elevation and floodproofing and/or elevation
certificates for all buildings constructed subject to this
chapter.
I. STATE PERMITS.
Ensure that construction authorization has been granted by
IDNR/OWR for all development projects subject to sections 8-11-7
and 8-11-8 of this chapter, unless enforcement responsibility has
been delegated to the Village of Elk Grove Village. However, the
following review approvals are not delegated to the Village of Elk
Grove Village and shall require review or permits from IDNR/OWR.
1. Organizations which are exempt from this Ordinance, as per the
Illinois Compiled Statutes;
2. IDNR/OWR projects, dams or impoundment structures as defined in
Section 8-11-2 and all other state, federal or local unit of
government projects, including projects of the Village of Elk
Grove village and County except for those projects meeting the
requirements of subsection 8-11-7B7 of this chapter;
3. An engineer's determination that an existing bridge or culvert
crossing is not a source of flood damage and the analysis
indicating the proposed flood profile, per subsection 8-11-
7133e;
4. An engineer's analysis of the flood profile due to subsection
8-11-7B3d;
5. Alternative transition sections and hydraulically equivalent
compensatory storage as indicated in subsections 8-11-7B3 (a,
b, and h).
6. Permit issuance of structures within, under or over publicly
navigable rivers, lakes and streams;
7. Any changes in the Base Flood Elevation or floodway locations;
and,
8. Base Flood Elevation determinations where none now exist.
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J. COOPERATION WITH OTHER AGENCIES:
1. Cooperate with State and Federal floodplain management agencies
to improve base flood or 100 -year frequency flood and floodway
data and to improve the administration of this Ordinance.
2. Submit data to IDNR/OWR and the Federal Emergency Management
Agency for proposed revisions of a regulatory map.
3. Submit reports as required for the National Flood Insurance
Program; and
4. Notify the Federal Emergency Management Agency of any proposed
amendments to this Ordinance.
K. PROMULGATE REGULATIONS:
Promulgate rules and regulations as necessary to administer and
enforce the provisions of this Ordinance, subject however to the
review and approval of IDNR/OWR and FEMA for any Ordinance
changes.
8-11-5:
BASE FLOOD ELEVATION: This Ordinance's protection standard is based on the
Flood Insurance Study for the Village of Elk Grove Village. If a base
flood elevation of 100 -year frequency flood elevation is not available for
a particular site, then the protection standard shall be according to the
best existing data available in the Illinois State Water Survey's Flood
Plain Information Repository that has been approved by IDNR/OWR and FEMA.
When a party disagrees with the best available data, he/she may finance the
detailed engineering study needed to replace existing data with better data
and submit it to IDNR/OWR and FEMA.
A.The base flood or 100 -year frequency flood elevation for the
SFHA's of Salt Creek, the Elk Grove Boulevard Drainage Ditch, the
Unnamed Creek, the West Branch of Salt Creek, and the Tributary to
the West Branch of Salt Creek shall be as delineated on the 100 -
year flood profiles in the Flood Insurance Study of the Village of
Elk Grove Village prepared by FEMA and dated November 6, 2000 and
for the DuPage County portions of the Village, the 100 -year
profiles are shown in the DuPage County FIS dated 10/8/88 and such
amendments to such study and maps as may be prepared from time to
time.
B.The base flood or 100 -year frequency flood elevation for the SFHA's
of those parts of unincorporated Cook County that are within the
one and half mile extraterritorial jurisdiction of the Village of
Elk Grove Village or that may be annexed into the Village shall be
as delineated on the 100 -year flood profiles in the countywide
Flood Insurance Study for Cook County prepared by FEMA and dated
November 6, 2000 and in the Flood Insurance Study for DuPage County
prepared by FEMA and dated October 18, 1988 and such amendments or
- 14
revisions to such study and maps as may be prepared from time to
time.
C.The base flood or 100 -year frequency flood elevation for each SFHA
delineated as an "AH Zone" or "AO Zone" shall be that elevation (or
depth) delineated on the Flood Insurance Rate Map of the Village of
Elk Grove Village.
D.The base flood or 100 -year frequency flood elevation for each of
the remaining SFHA's delineated as an "A Zone" on the Flood
Insurance Rate Map of the Village of Elk Grove Village shall
be according to the best existing data available in the Illinois
State Water Survey Floodplain Information Repository.
1. When no base flood or 100 -year frequency flood elevation
exists, the base flood or 100 -year frequency flood elevation for
a riverine SFHA shall be determined from a backwater model such
as HEC -II, WSP-2, or a dynamic model such as HIP.
2. The flood flows used in the hydraulic models shall be obtained
from a hydrologic model such as HEC -1 TR -20, or HIP, or by
techniques presented in various publications prepared by the
United States Geological Survey for estimating peak flood
discharges.
3. Along any watercourses draining more than one (1) square mile,
the above analyses shall be submitted to IDNR/OWR for approval.
Once approved it must be submitted to the Illinois State Water
survey Floodplain Information Repository for filling.
4. For a non-riverine SFHA, the Base Flood Elevation shall be the
historic Flood of Record plus three feet, unless calculated by a
detailed engineering study and approved by IDNR/OWR for drainage
areas greater than one square mile.
5. For an unmapped extended SFHA (with a drainage area less than
one square mile) which has been identified by the Director of
Engineering & Community Development pursuant to subsection 8-11-
4A3, the base flood elevation shall be determined by the
applicant utilizing a method as approved in section 8-11-5, with
concurrence of the Director of Engineering & Community
Development.
8-11-6
OCCUPATION AND USE OF FLOOD FRINGE AREAS: Development in and/or filling of
the flood fringe will be permitted if protection is provided against the
base flood or 100 -year frequency flood by proper elevation, and
compensatory storage, and other applicable provisions of this Ordinance.
No use will be permitted which adversely affects the capacity of drainage
facilities or systems. Development located within the flood fringe shall
meet the requirements of this Section, along with the requirements of 8-11-
9.
- 15 -
A. Development Permit:
1. No person, firm, corporation, or governmental body not exempted
by state law shall commence any development in the SFHA without
first obtaining a development permit from the Director of
Engineering and Community Development.
2. Application for a development permit shall be made on a form
provided by the Director of Engineering and Community
Development.
a) The application shall be accompanied by drawings of the
site, drawn to scale, showing property line dimensions and
legal description for the property and sealed by a licensed
engineer, architect or land surveyor; existing grade
elevations in M.S.L., 1929 adj. Datum or N.G.V.D. and all
changes in grade resulting from excavation or filling; the
location and dimensions of all buildings and additions to
buildings.
b) For all proposed buildings, the elevation of the lowest
floor (including basement) and lowest adjacent grade shall
be shown on the submitted plans and the development will be
subject to the requirements of Section 8-11-9 of this
chapter.
3. Upon receipt of a development permit application, the Director of
Engineering and Community Development shall compare the elevation
of the site to the base flood or 100 -year frequency flood
elevation.
a) Any development located on land that can be shown to be
higher than the base flood elevation of the current Flood
Insurance Rate Map and which has not been filled after the
date of the site's first Flood Insurance Rate Map without a
permit, as required by this ordinance, is not in the SFHA
and, therefore, not subject to the requirements of this
chapter.
b) The Director of Engineering & Community Development shall
maintain documentation of the existing ground elevation at
the development site and certification that this ground
elevation existed prior to the date of the site's first
Flood Insurance Rate Map identification.
4. A soil erosion and sedimentation control plan for disturbed areas
shall be submitted. This plan shall include a description of the
sequence of grading activities and the temporary sediment and
erosion control measures to be implemented to mitigate their
effects. This plan shall also include a description of final
stabilization and revegetation measures, and the identification
of a responsible party to ensure post -construction maintenance.
- 16 -
5. The Director of Engineering and Community Development shall be
responsible for obtaining from the applicant, copies of all other
local, state and federal permits, approvals or permit -not -
required letters that may be required for this type of activity.
The Director of Engineering and Community Development shall not
issue a permit unless all other local, state, and federal permits
have been obtained.
B. Preventing increased Damages. No development in the flood fringe
shall create a threat to public health and safety.
1. If fill is being used to elevate the site above the base flood or
100 -year frequency flood elevation, the applicant shall submit
sufficient data and obtain a letter of map revision (LOMB) from
FEMA for the purpose of removing the site from the floodplain.
2. Compensatory Storage:
a) Whenever any portion of a floodplain is authorized for use,
the volume of space which will be occupied by the authorized
fill or structure below the base flood or 100 -year frequency
flood elevation shall be compensated for and balanced by a
hydraulically equivalent volume of excavation taken from
below the base flood or 100 -year frequency flood elevation.
b) The excavation volume shall be at least equal to 1.5 times
the volume of storage lost due to the fill or structure.
c) In the case of streams and watercourses, such excavation
shall be made opposite or adjacent to the areas so filled or
occupied.
d) All floodplain storage lost below the existing 10 -year flood
elevation shall be replaced below the proposed 10 -year flood
elevation. All floodplain storage lost above the existing
10 -year flood elevation shall be replaced above the proposed
10 -year flood elevation.
e) All such excavations shall be constructed to drain freely
and openly to the watercourse.
8-11-7:
OCCUPATION AND USE OF IDENTIFIED FLOODWAYS: This section applies to
proposed development, redevelopment, site modification or building
modification within a regulatory floodway. The compensatory floodway for
Salt Creek, the Elk Grove Boulevard Drainage Ditch, the Unnamed Creek, the
West Branch of Salt Creek, and the Tributary to the west Branch of Salt
Creek shall be as delineated on the designated floodway maps designated by
IDNR/OWR according to and referenced in Section 8-11-2. Only those uses and
structures will be permitted which meet the criteria in this section. All
floodway modifications shall be the minimum necessary to accomplish the
- 17 -
purpose of the project. The development shall also meet the requirements
of Section 8-11-9.
A. Development Permit. No person, firm, corporation or
governmental body not exempted by state law shall commence any
development in a floodway without first obtaining a development
permit from the Director of Engineering and Community
Development and IDNR/OWR.
1. Application for a development permit shall be made on a form
provided by the Director of Engineering and Community
Development. The application shall include the following
information:
a) Name and address of applicant;
b) Site location (including legal description) of the
property, drawn to scale, on the designated floodway map,
indicating whether it is proposed to be in an
incorporated or unincorporated area;
c) Name of stream or body of water affected;
d) Description of proposed activity;
e) Statement of purpose of proposed activity;
f) Anticipated dates of initiation and completion
of activity;
g) Name and mailing address of the owner of the subject
property if different from the applicant;
h) Signature of applicant or the applicant's agent;
i) If the applicant is a corporation, the president or other
authorized officer shall sign the application form;
j) If the applicant is a partnership, each partner shall
sign the application form; and
k) If the applicant is a land trust, the trust officer shall
sign the name of the trustee by him (her) as trust
officer. A disclosure affidavit shall be filed with the
application, identifying each beneficiary of the trust by
name and address and defining the respective interests
therein.
1). Plans of the proposed activity shall be provided which include
as a minimum:
(1) A vicinity map showing the site of the
activity, name of the waterway, boundary
- 18
lines, names of roads in the vicinity of
the site, graphic or numerical scale,
and north arrow;
(2) A plan view of the project and engineering
study reach showing existing and proposed
conditions including principal dimensions
of the structure of work, elevations in
mean sea lever (1929 adjustment) datum or
N.G.V.C., adjacent property lines and ownership,
drainage and flood control easements, location
of any channels and any existing or future access
roads, distance between proposed activity and
navigation channel (when the proposed construction
is near a commercially navigable body of water),
designated floodway limit, flood plain limit,
specifications and dimensions of any proposed channel
modifications, location and orientation of
cross-sections, north arrow, and a graphic or numerical
scale;
(3) Cross section views of the project and engineering study
reach showing existing and proposed conditions including
principal dimensions of the work as shown in plan
view, existing and proposed elevations, normal water
elevation, 10 -year frequency flood elevation, 100 -year
frequency flood elevation, and graphic or numerical scales
(horizontal and vertical);
(4) A soil erosion and sedimentation control plan for
disturbed areas. This plan shall include a description of
the sequence of grading activities and the temporary
sediment and erosion control measures to be implemented to
mitigate their effects. This plan shall also include a
description of final stabilization and revegetation
measures, and the identification of a responsible party to
ensure post -construction maintenance.
(5) A copy of the designated floodway map, marked to reflect
any proposed change in the designated floodway location.
M. Any and all other local, state and federal permits or approval
letters that may be required for this type of development.
n. Engineering calculations and supporting date shall be submitted
showing that the proposed work will meet the permit criteria of
subsection B of this section.
o. If the designated floodway delineation, base flood or 100 -year
frequency flood elevation will change due to the proposed
project, the application will not be considered complete until
IDNR/OWR has indicated conditional approval of the designated
- 19 -
floodway map change. No structures may be built until a Letter
of Map Revision has been approved by FEMA.
P. The application for a structure shall be accompanied by
drawings of the site, drawn to scale showing property line
dimensions and existing ground elevations and all changes in
grade resulting from any proposed excavation or filling, and
flood plain and floodway limits; sealed by a registered
professional engineer, licensed architect or registered land
surveyor; the location and dimensions of all buildings and
additions to buildings; and the elevation of the lowest floor
(including basement) of all proposed buildings subject to the
requirements of Section 8-11-9 of this chapter.
q. If the proposed project involves a channel modification, the
Applicant shall submit the following information:
(1) A discussion of the purpose of and need for the proposed
work;
(2) A discussion of the feasibility of using alternative
locations or methods (see 8-11-7B3A) to accomplish the
purpose of the proposed work;
(3) An analysis of the extent and permanence of the impacts
each feasible alternative identified in 8-11-7B3A. Of this
section would have on the physical and biological
conditions of the body of water affected; and
(4) An analysis of the impacts of the proposed project,
considering cumulative effects on the physical and
biological conditions of the body of water affected.
2. The Director of Engineering and Community Development shall be
responsible for obtaining from the applicant copies of all
other local, state, and federal permits and approvals that may
be required for this type of activity.
a) The Director of Engineering and Community Development shall
not issue the development permit unless all required Federal
and State permits have been obtained.
b) A Registered Professional Engineer, under the employ or
contract of the Village of Elk Grove Village shall review
and approve applications reviewed under this Section.
B. Preventing increased Damages and a list of Appropriate Uses:
1. The only development in a floodway which will be allowed are
Appropriate Uses, which will not cause a rise in the base flood
elevation, and which will not create a damaging or potentially
damaging increase in flood heights or velocity or be a threat
to public health and safety and welfare or impair the natural
20 -
hydrologic and hydraulic functions of the floodway or channel,
or permanently impair existing water quality or aquatic
habitat. Construction impacts shall be minimized by
appropriate mitigation methods as called for in this Ordinance.
Only those Appropriate Uses listed in 92 Ill. Adm. Code 708
will be allowed. Appropriate uses do not include the
construction or placement of any new structures, fill, building
additions, buildings on stilts, excavation or channel
modifications done to accommodate otherwise nonappropriate uses
in the floodway, fencing (including landscaping or planting
designed to act as a fence) and storage of materials except as
specifically defined above as an Appropriate Use. The approved
Appropriate Uses are as follows:
a) Flood control structures, dikes, dams and other
public works or private improvements relating to
the control of drainage, flooding, erosion, or
water quality or habitat for fish and wildlife.
b) Structures or facilities relating to the use
of, or requiring access to, the water or
shoreline, such as pumping and treatment
facilities, and facilities and improvements
related to recreational boating, commercial
shipping and other functionally water dependent
uses.
c) Storm and sanitary sewer relief outfalls.
d) Underground and overhead utilities.
e) Recreational facilities such as playing fields
and trail systems including any related fencing
(at least 50% open when viewed from any one
direction) built parallel to the direction of
flood flows, and including open-air pavilions and toilet
facilities (4 -stall maximum) that will not block flood
flows not reduce floodway storage.
f) Detached garages, storage sheds, or other non -
habitable accessory structures that will not
block flood flows, nor reduces floodway storage.
g) Bridges, culverts, roadways, sidewalks, railways,
runways and taxiways and any modification thereto.
h) Parking lots built at or below existing grade where
either .
(1) The depth of flooding at the 100 -year
frequency flood event will not exceed 1.0 foot;
or
- 21 -
(2) The applicant of a short-term recreational use
facility parking lot, formally agrees to restrict
access during overbank flooding events and accepts
liability for all damage caused by vehicular access
during all overbank flooding events.
i) Designated floodway regrading, without fill, to create a
positive non-erosive slope toward a watercourse.
j) Floodproofing activities to protect previously existing
lawful structures including the construction of water
tight window wells, elevating structures, or construction
of floodwalls around residential, commercial or industrial
principal structures where the outside toe of the
floodwall shall be no more than ten (10)feet away from the
exterior wall of the existing structure, and, which are not
considered substantial improvements to the structure.
k) The replacement, reconstruction, or repair of a damaged
building, provided that the outside dimensions are not
increased, and if the building was damaged to 50 percent or
more of the market value before the damage occurred, the
building will be protected from flooding to the flood
protection elevation.
1) Modifications to an existing building that would not
increase the enclosed floor area of the building below the
100 -year frequency flood elevation, and which will not
block flood flows including but not limited to, fireplaces,
bay windows, decks, patios, and second story additions. If
the building improved to 50 percent or more of the market
value before the modification occurred (i.e., a substantial
improvement), the building will be protected from flooding
to the flood protection elevation.
2. Appropriate uses do not include the construction or
placement of any new structures, fill, building additions,
buildings on stilts, excavation or channel modifications
done to accommodate otherwise non -appropriate uses in the
floodway, fencing (including landscaping or planting
designated to act as a fence) and storage of materials
except as specifically defined as an Appropriate Use.
3. Within the designated floodway as identified on the floodway
maps designated by IDNR/OWR, the construction of an
Appropriate Use, will be considered permissible provided
that the proposed project meets the following engineering
and mitigation criteria and is so stated in writing with
supporting plans, calculations and data by a registered
professional engineer and provided that any structure meets
the protection requirements of Section 8-11-9 of this
chapter:
�40M
a) Preservation of Flood Conveyance, so as Not to Increase
Flood Stages Upstream. For appropriate uses other than
bridge or culvert crossings, on -stream structures or
dams, all effective designated floodway conveyance lost
due to the project will be replaced for all flood events
up to and including the 100 -year frequency flood. In
calculating effective designated floodway conveyance, the
following factors shall be taken into consideration:
(1) Designated floodway conveyance,
"K" = 1.486 A R"'
n
where "n" is Mannings roughness factor,
"A" is the effective flow area of the
cross-section, and "R" is the ratio of
the area to the wetted perimeter. (see
Open Channel Hydraulics, Ven Te chow,
1959, McGraw-Hill Book Company, New York)
(2) The same Manning's "n" value shall be used
for both existing and proposed conditions
unless a recorded maintenance agreement
with a federal, state, or local unit of
government can assure the proposed
conditions will be maintained or the land
cover is changing from a vegetative to a
non -vegetative land cover.
(3) Transition sections shall be provided
and used in calculations of effective
designated floodway conveyance. The
following expansion and contraction ratios
shall be used unless an applicant's
engineer can prove to IDNR/OWR through
engineering calculations or model tests
that more abrupt transition may be used
with the same efficiency:
A. When water is flowing from a narrow
Section to a wider section, the water
should be assumed to expand no faster
than at a rate of one foot horizontal
for every four feet of the flooded
stream's length.
B. When water is flowing from a wide
section to a narrow section, the water
should be assumed to contract no faster
than at a rate of one foot horizontal
for every one foot of the flooded
stream's length.
- 23 -
C. When expanding or contracting flows in
a vertical direction, a minimum of one
foot vertical transition for every ten
feet of stream length shall be used.
D. Transition sections shall be provided
between cross-sections with rapid
expansions and contractions and when
meeting the designated floodway
delineation on adjacent properties.
E. All cross-sections used in the
calculations shall be located
perpendicular to flood flows.
b. Preservation of Floodway Storage so as Not to Increase
Downstream Flooding.
(1) Compensatory storage shall be provided for any
designated floodway storage lost due to the
proposed work from the volume of fill or structures
placed and the impact of any related flood control
projects.
(2) Compensatory storage for fill or structures shall
be equal to at least 1.5 times the volume of flood
plain storage lost.
(3) Artificially created storage lost due to a
reduction in head loss behind a bridge shall not be
required to be replaced.
(4) The compensatory designated floodway storage shall
be placed between the proposed normal water
elevation and the proposed 100 -year flood
elevation. All designated floodway storage lost
below the existing 10 -year flood elevation shall be
replaced below the proposed 10 -year flood
elevation. All designated floodway storage lost
above the existing 10 -year flood elevation shall be
replaced above the proposed 10 -year flood
elevation. All such excavations shall be
constructed to drain freely and openly to the
watercourse.
(5) If the compensatory storage will not be placed at
the location of the proposed construction, the
applicant's engineer shall demonstrate to IDNR/OWR
through a determination of flood discharges and
water surface elevations that the compensatory
storage is hydraulically equivalent.
24 -
(6) There shall be no reduction in floodway surface
area as a result of a floodway modification, unless
such modification is necessary to reduce flooding
at existing structure.
c. Preservation of Floodway Velocities so as Not to Increase Stream
Erosion or Flood Heights.
(1) For all Appropriate Uses, except bridges or
culverts or on stream structures, the proposed work
will not result in an increase in the average
channel or designated floodway velocities or stage
for all flood events up to and including the 100 -
year frequency event.
(2)In the case of bridges or culverts or on stream
structures built for the purpose of backing up
water in the stream during normal or flood flows,
velocities may be increased at the structure site
if scour, erosion and sedimentation will be avoided
by the use of riprap or other design measures.
d. Construction of New Bridges or Culvert Crossings and Roadway
Approaches.
(1)The proposed structure shall not result in an
increase of upstream flood stages greater than 0.1
foot when compared to the existing conditions for
all flood events up to and including the 100 -year
frequency event; or the upstream flood stage
increases will be contained within the channel
banks (or within existing vertical extensions of
the channel banks) such as within the design
protection grade of existing levees or flood walls
or within recorded flood easements.
(2)If the proposed construction will increase upstream
flood stages greater than 0.1 feet, the developer
must contact IDNR/OWR to obtain a permit for a dam
or waiver.
A. The engineering analysis of upstream
flood stages must be calculated using the
flood study flows, and corresponding
flood elevations for tailwater
conditions for the flood study specified
in Section 8-11-5 of this chapter.
Culverts must be analyzed using the U.S.
DOT, FHWA Hydraulic Chart for the
Selection of Highway Culverts. Bridges
must be analyzed using the U.S. DOT/
Federal Highway Administration
Hydraulics of Bridge Waterways
- 25 -
calculation procedures.
B. Lost floodway storage must be
compensated for per subsection B36 of
this section.
C. velocity increases must be mitigated per
subsection B3c of this section.
D. If the crossing is proposed over a public
water that is used for recreational or
commercial navigations, an IDNR/OWR
permit must be received.
E. The hydraulic analysis for the backwater
caused by the bridge showing the existing
condition and proposed regulatory profile
must be submitted to IDNR/OWR for
concurrence that a CLOMR is not required
by subsecton B1 of this section.
F. All excavations for the construction of
the crossing shall be designed per
subsection B3h of this section.
e. Reconstruction or Modification of Existing
Bridges, Culverts, and Approach Roads.
(1) The bridge or culvert and roadway approach
reconstruction or modification shall be
constructed with no more than 0.1 foot
increase in backwater over the existing
flood profile for all flood frequencies up
to and including the 100 -year event, if
the existing structure is not a source of
flood damage.
(2) If the existing bridge or culvert and
roadway approach is a source of flood
damage to buildings or structures in the
upstream flood plain, the applicant's
engineer shall evaluate the feasibility of
redesigning the structure to reduce the
existing backwater, taking into consideration the
effects on flood stages on upstream and downstream
properties.
(3) The determination as to whether or not
the existing crossing is a source of flood
damage and should be redesigned must be
prepared in accordance with the Department
of Transportation Rules 92 Ill. Adm. Code 708
(Floodway Construction in Northeastern Illinois)
�X-�
and submitted to IDNR/OWR for review and concurrence
before a permit is issued.
f. On -Stream Structures Built for the Purpose of Backing Up Water.
1)Any increase in upstream flood stages greater than 0.0
foot when compared to the existing conditions, for
all flood events up to and including the 100 -year
frequency event shall be contained within the channel
banks (or within existing vertical extensions of the
channel banks) such as within the design protection
grade of existing levees or flood walls or within
recorded flood easements.
(2) A permit or letter indicating a permit is not
required must be obtained from IDNR/OWR for any
structure built for the purpose of backing up water
in the stream during normal or flood flow.
(3) All dams and impoundment structures as defined in
Section 8-11-2 shall meet the permitting requirements
of 92 Ill. Adm. Code Part 702 (Construction and
Maintenance of Dams). If the proposed activity
involves a modification of the channel or floodway to
accommodate an impoundment, it shall be demonstrated
that:
(A) The impoundment is determined to be in
the public interest by providing flood
control, public recreation, or regional
stormwater detention;
(B) The impoundment will not prevent the
migration of indigenous fish species, which
require access to upstream areas as part of
their life cycle, such as for spawning;
(C) The impoundment will not cause or contribute
to degraded water quality or habitat
conditions. Impoundment design
should include gradual bank slopes,
appropriate bank stabilization measures,
and a pre -sedimentation basin.
(D) A non -point source control plan has been
implemented in the upstream watershed to
control the effects of sediment runoff as
well as minimize the input of nutrients, oil
and grease, metals, and other pollutants. If
there is more than one municipality in the
upstream watershed, the municipality in which
the impoundment is constructed should
- 27 -
coordinate with upstream municipalities to
ensure comprehensive watershed control;
(E) The project otherwise complies with the
requirements of Section 6-11-7.
g. Flood Proofing of Existing Habitable, Residential and Commercial
Structures.
(1) If construction is required beyond the outside
dimensions of the existing building, the outside
perimeter of the floodproofing construction shall be
placed no further than 10 feet from the outside of
the building.
(2) Compensation of lost storage and conveyance will not
be required for floodproofing activities.
h. Excavation in the Floodway.
(1)When excavation is proposed in the design of bridges
and culvert openings, including the modifications to
and replacement of existing bridge and culvert
structures, or to compensate for lost conveyance for
other Appropriate Uses, transition sections shall be
provided for the excavation.
(2)The following expansion and contraction ratios shall
be used unless an applicant's engineer can prove to
IDNR/OWR through engineering calculations or model
tests that more abrupt transitions may be used with
the same efficiency:
(A) When water is flowing from a narrow section
to a wider section, the water should be
assumed to expand no faster than at a rate of
one foot horizontal for every four feet of
the flooded stream's length;
(B) When water is flowing from a wide section to
a narrow section, the water should be assumed
to contract no faster than at a rate of one
foot horizontal for ever one foot of the
flooded stream's length; and
(C) When expanding or contracting flows in a
vertical direction, a minimum of one foot
vertical transition for every ten feet of
stream length shall be used.
(D) Erosion/scour protection shall be provided
inland, upstream and downstream of the
transition sections.
- 28 -
i. If the proposed activity involves a channel modification,
it shall be demonstrated that:
(1) There are no practicable alternatives to the
activity which would accomplish its purpose
with less impact to the natural conditions of
the body of water affected. Possible
alternatives include levees, bank
stabilization, floodproofing of existing
structures, removal of structures from the
floodplain, clearing the channel, high flow
channel, or the establishment of a stream side
buffer strip or green belt. Channel
modification is acceptable if the purpose is
to restore natural conditions and improve
water quality and fish and wildlife habitat;
(2) water quality, habitat, and other natural
functions would be significantly improved by
the modifications and no significant habitat
area may be destroyed, or the impacts are
offset by the replacement of any equivalent
degree of natural resource values;
(3) The activity has been planned and designed and
will be constructed in a way which will
minimize its adverse impacts on the natural
conditions of the body of water affected,
consistent with the following criteria:
(A)The physical characteristics of the
modified channel shall match as closely as
possible those of the existing channel in
length, cross section, slope and
sinuosity. If the existing channel has
been previously modified, restoration of
more natural physical conditions should be
incorporated into channel modification
design, where practical.
(B)Hydraulically effective transitions shall
be provided at both the upstream and
downstream ends of the project, designed
such that they will prevent erosion.
(C)One-sided construction of a channel shall
be used when feasible. Removal of
streamside (riparian) vegetation should be
limited to one side of the channel, where
possible, to preserve the shading and
stabilization effects of the vegetation.
- 29 -
(D)Clearing of stabilizing vegetation shall
be limited to that which is essential for
construction of the channel.
(E)Channel banks shall be constructed with a
side slope no steeper than 3:1 horizontal
to vertical, wherever practicable. Native
vegetation and gradual side slopes are the
preferred methods for bank stabilization.
Where high velocities or sharp bends
necessitate the use of alternative
stabilization measures, soil
bioengineering techniques, natural rock or
riprap are preferred approaches.
Artificial materials such as concrete,
gabions, or construction rubble should be
avoided unless there are no practicable
alternatives.
(F)All disturbed areas associated with the
modification shall be seeded or otherwise
stabilized as soon as possible upon
completion of construction. Erosion
blanket or an equivalent material shall be
required to stabilize disturbed channel
banks prior to establishment of the
vegetative cover.
(G)If the existing channel contains
considerable bottom diversity such as deep
pools, riffles, and other similar
features, such features shall be provided
in the new channel. Spawning and nesting
areas and flow characteristics compatible
with fish habitat shall also be
established, where appropriate.
(H)A sediment basin shall be installed at the
downstream end of the modification to
reduce sedimentation and degradation of
downstream water quality.
(I)New or relocated channels should be built
in the dry and all items of construction,
including vegetation, should be completed
prior to diversion of water into the new
channel.
(J)There shall be no increases in stage or
velocity as the channel enters or leaves
the project site for any frequency flood
unless necessitated by a public flood
control project or unless such an increase
- 30 -
is justified as part of a habitat
improvement or erosion control project.
(K)Unless the modification is for a public
flood control project, there shall be no
reduction in the volume of floodwater
storage outside the floodway as a result
of the modification; and
(4) The project otherwise complies with the
requirements of Section 8-11-7.
j. Seeding and Stabilization Plan.
For all activities located in a floodway, a seeding and
stabilization plan shall be submitted by the applicant.
k. Soil Erosion and Sedimentation Measures.
For all activities in the floodway, including grading,
filling, and excavation, in which there is potential for
erosion of exposed soil, soil erosion and sedimentation
control measures shall be employed consistent with the
following criteria:
(1) The construction area shall be minimized
to preserve the maximum vegetation
possible. construction shall be scheduled
to minimize the time soil is exposed and
unprotected. In no case shall the
existing natural vegetation be destroyed,
removed, or disturbed more than 15 days
prior to the initiation of improvements.
(2) Temporary and/or permanent soil stabilization shall
be applied to denuded areas as soon as possible.
As a minimum, soil stabilization shall be provided
within 15 days after final grade is reached on any
portion of the site, and within 15 days to denuded
areas which may not be at final grade but will
remain undisturbed for longer than 60 days.
(3) Sedimentation control measures shall be installed
before any significant grading or filling is
initiated on the site to prevent the movement of
eroded sediments off site or into the channel.
Potential sediment control devices include filter
fences, straw bale fences, check dams, diversion
ditches, and sediment traps and basins.
(4) A vegetated buffer strip of at least 25 feet in
width shall be preserved and/or re-established,
where possible, along existing channels (See 8-11-
- 31 -
7B3P. Construction vehicle use of channels shall
be minimized. Temporary stream crossings shall be
constructed, where necessary, to minimize erosion.
Necessary construction in or along channels shall
be reestablished immediately.
(5) Soil erosion and sedimentation control measures
shall be designed and implemented consistent with
"Procedures and Standards for Urban Soil Erosion
and Sedimentation Control in Illinois" (1988) also
known as the "Green Book" and "The Illinois Urban
Manual" (NRCS, 1995).
1. Public Flood Control Projects. For public flood control
projects, the permitting requirements of this section will be
considered met if the applicant can demonstrate to IDNR/OWR
through hydraulic and hydrologic calculations that the proposed
project will not singularly or cumulatively result in increased
flood heights outside the project right-of-way or easements for
all flood events up to and including the 100 -year frequency
event.
M. General Criteria for Analysis of Flood Elevations.
(1) The flood profiles, flows and floodway data in the
designated floodway study, referenced in Section 8-
11-5, must be used for analysis of the base
conditions. If the study data appears to be in
error or conditions have changed, IDNR/OWR shall be
contacted for approval and concurrence on the
appropriate base conditions data to use.
(2) If the 100 -year designated floodway elevation at the
site of the proposed construction is affected by
backwater from a downstream receiving stream with a
larger drainage area; the proposed construction
shall be shown to meet:
(A)The requirements of this section for the 100 -year
frequency flood elevations of the designated
floodway conditions, and
(B)Conditions with the receiving stream at normal
water elevations.
(3) If the applicant learns from IDNR/OWR, local
governments, or a private owner that a downstream
restrictive bridge or culvert is scheduled to be
removed, reconstructed, modified, or a regional
flood control project is scheduled to be built,
removed, constructed or modified within the next
five years, the proposed construction shall be
analyzed and shown to meet the requirements of this
- 32
section for both the existing conditions and the
expected flood profile conditions when the bridge,
culvert or flood control project is built.
n. Conditional Letter of Map Revision.
(1) If the Appropriate Use would result in a change in
the designated floodway location or the 100 -year
frequency flood elevation, the applicant shall
submit to IDNR/OWR and to FEMA all the information,
calculations and documents necessary to be issued a
conditional designated floodway map revision and
receive from IDNR/OWR a conditional concurrence of
the designated floodway change before a permit is
issued.
(2) The final regulatory floodway map will not be
changed by FEMA until as -built plans or record
drawings of initial filling, grading, dredging, or
excavating activities are submitted and accepted by
FEMA and IDNR/OWR.
(3) In the case of non-government projects, the
municipality in incorporated areas and the county
in unincorporated areas shall concur with the
proposed conditional designated floodway map
revision before IDNR/OWR approval can be given.
(4) No filling, grading, dredging or excavating shall
take place until a conditional approval is issued.
(5) After initial filling, grading, dredging or
excavating, no activities shall take place until a
final Letter of Map Revision (LOMR) is issued by
FEMA with concurrence from IDNR/OWR.
o. Professional Engineer's Supervision. All engineering analyses
shall be performed by or under the supervision of a Registered
Professional Engineer.
p. For all activities in the floodway involving construction
within 25 feet of the channel, the following criteria shall be
met:
1. A natural vegetation buffer strip shall be
preserved within at least 25 feet of the ordinary
high water mark of the channel.
2. Where it is impossible to protect this buffer strip
during the construction of an Appropriate Use, a
vegetated buffer strip shall be established upon
completion of construction.
- 33 -
q. After receipt of conditional approval of the designated
floodway change and issuance of a permit and a Conditional
Letter of Map Revision, construction as necessary to change the
floodway designation may proceed but no buildings or structures
or other construction that is not an Appropriate Use may be
placed in that area until the designated floodway map is
changed and a final Letter of Map Revision is received. The
designated floodway map will be revised upon acceptance and
concurrence by IDNR/OWR and FEMA of the "as built" plans.
4. Development Activities in Delegated Communities Requiring State
Review.
For those projects listed below located in a designated floodway,
the following criteria shall be submitted to IDNR/OWR for their
review and concurrence prior to the issuance of a permit by a
community or county delegated state permitting authority in the
floodway.
a) An engineer's analysis of the flood profile due to a
proposed bridge pursuant to Section 8-11-7B3d.
b) An engineer's determination that an existing bridge or
culvert crossing is not a source of flood damage and the
analysis indicating the proposed flood profile, pursuant
to Section 8-11-7B3e.
c) Alternative transition sections and hydraulically
equivalent storage pursuant to Section 8-11-7B3 (a, b and
h) .
d) The construction of any IDNR/OWR projects, dams (as
defined in Section 6-11-2 and all other state, federal,
or local units of government projects, including projects
of the municipality or county.
e) An engineer's determination that a proposed bridge
affected by backwater from a downstream receiving stream
may be built with a smaller opening.
f) Projects which revise or establish the floodway and/or
flood profiles.
g) Projects in public bodies of water.
5. Other Permits.
a) In addition to the other requirements of this Ordinance,
a development permit for a site located in a floodway
shall not be issued unless the applicant first obtains a
permit or written documentation that a permit is not
required from IDNR/OWR, issued pursuant to 615 ILLS 5/5
et seq.
- 34
b) No permit from IDNR/OWR shall be required if IDNR/OWR has
delegated this responsibility to the Village of Elk Grove
Village.
6. Permits for Dams.
a) Any work involving the construction, modification or
removal of a dam as defined on Section 8-11-2 per 92 Ill.
Adm. Code 702 (Rules for Construction of Dams) shall
obtain an IDNR/OWR permit prior to the start of
construction of a dam.
b) If the Director of Engineering and Community Development
finds a dam that does not have an IDNR/OWR permit the
Director of Engineering and Community Development shall
immediately notify the IDNR/OWR Schaumburg office.
c) If the Director or Engineering and Community Development
finds a dam which is believed to be in unsafe condition,
the Director of Engineering and Community Development
shall immediately notify the owner of the dam, the
IDNR/OWR Schaumburg office, and the Illinois Emergency
Management Agency (IEMA).
7. Activities That Do Not Require a Registered Professional Engineer's
Review. The following activities may be permitted without a
Registered Professional Engineer's review. Such activities
shall still meet the other requirements of this Ordinance,
including the mitigation requirements.
a) Underground and overhead utilities that:
(1) Do not result in any increase in existing
ground elevations, or
(2) Do not require the placement of above
ground structures in the floodway, or
(3) In the case of underground stream
crossings, the top of the pipe or
encasement is buried a minimum of 3'
below the existing stream bed, and
(4) Overhead utility lines shall be constructed above
the estimated 100 -year frequency flood elevation or
attached above the low chord of an existing bridge
(with the permission of the bridge owner). No
supporting towers shall be placed in the
watercourse and shall be designed so as to not
catch debris.
�36�
(5) Disturbance of streamside vegetation shall be kept
to minimum during construction to prevent erosion
and sedimentation. All disturbed floodway areas,
including the streambanks shall be restored to
their original contours and seeded or otherwise
stabilized upon completion of construction.
(6) A utility crossing carrying material which may
cause water pollution as defined by the
Environmental Protection Act 415 ILCS 5 (1992 State
Bar Edition) shall be provided with shut-off valves
on each side of the body of water to be crossed.
(7) All Illinois Commerce Commission, National Electric
Safety Codes, and federal requirements for
clearance must be met.
b. Storm and sanitary sewer outfalls that:
(1) Do not extend riverward or lakeward of
the existing adjacent natural bank slope,
and
(2) Do not result in an increase in ground
elevation, and
(3) Are designed so as not to cause stream
erosion at the outfall location.
C. Construction of sidewalks, athletic fields (excluding fences),
properly anchored playground equipment and patios at grade.
d. Construction of shoreline and streambank protection that:
(1) Does not exceed 1000 feet in length.
(2) Materials are not placed higher than the
existing top of bank.
(3) Materials are placed so as not to reduce
the cross-sectional area of the stream
channel or bank of the lake.
(4) Stabilization utilizing native vegetation and
gradual side slopes are the preferred mitigation
methods for existing erosion problems.
Where high channel velocities, sharp bends
or wave action necessitate the use of
alternative stabilization measures, soil
bioengineering techniques, natural rock or riprap
are preferred materials. Artificial materials such
as concrete, construction rubble, and gabions
should be avoided unless there are no
- 36 -
practicable alternatives.
e. Temporary stream crossings in which:
(1) The approach roads will be 0.5' (1/2
foot) or less above natural grade.
(2) The crossing will allow stream flow to
pass without backing up the water above
the streambank vegetation line or above
any drainage tile or outfall invert.
(3) The top of the roadway fill in the channel
will be at least 2' below the top of the
lowest bank. Any fill in the channel
shall be non-erosive material, such as
riprap or gravel.
(4) All disturbed streambanks will be seeded
or otherwise stabilized as soon as
possible upon installation and again upon
removal of construction.
(5) The access road and temporary crossings
will be removed within one year after
authorization.
8-11-8:
OCCUPATION AND USE OF SFHA AREAS WHERE FLOODWAYS ARE NOT IDENTIFIED:
In SFHA or floodplains (including AE, AH, AO and Unnumbered A Zones) where
no floodways have been identified and no base flood or 100 -year frequency
flood elevations have been established by FEMA, and draining more than a
square mile, no development shall be permitted unless the cumulative effect
of the proposals, when combined with all other existing and anticipated
uses and structures, shall not significantly impede or increase the flow
and passage of the floodwaters nor significantly increase the base flood or
100 -year frequency flood elevation.
A. Development Permit.
1. No person, firm, corporation, or governmental body, not exempted by
state law, shall commence any development in a SFHA or floodplain
without first obtaining a development permit from the Director of
Engineering and Community Development.
2. Application for a development permit shall be made on a form provided
by the Director of Engineering and Community Development.
a) The application shall be accompanied by drawings of the
site, drawn to scale showing property line dimensions; and
existing grade elevations and all changes in grade resulting
from excavation or filling, sealed by a licensed engineer,
37 -
architect or surveyor; the location and dimensions of all
buildings and additions to buildings; and the elevations of
the lowest floor (including basement)of all proposed
buildings subject to the requirements of Section 9-11-9 of
this chapter.
b) The application for a development permit shall also include
the following information:
(1) A detailed description of the proposed activity,
its purpose, and intended use;
(2) Site location (including legal description) of
the property, drawn to scale, on the designated
floodway maps, indicating whether it is proposed to
be in an incorporated or unincorporated area;
(3) Anticipated dates of initiation and completion
of activity;
(4) Plans of the proposed activity shall be provided
which include as a minimum:
(A) A vicinity map showing the site of the
activity, name of the waterway, boundary
lines, names of roads in the vicinity of
of the site, graphic or numerical scale,
and north arrow:
(B) A plan view of the project and engineering
study reach showing existing and proposed
conditions including principal dimensions
of the structure or work, elevations in
mean sea level (1929 adjustment) datum or
N.G.V.D., adjacent property lines and
ownership, drainage and flood control
easements, distance between proposed
activity and navigation channel (when the
proposed construction is near a
commercially navigable body of water),
floodplain limit, location and
orientation of cross-sections, north
arrow, and a graphical or numerical scale;
(C) Cross-section views of the project
perpendicular to the flow of floodwater and
engineering study reach showing existing
and proposed conditions including
principal dimensions of the work as shown
in plan view, existing and proposed
elevations, normal water elevation, 10 -year
frequency flood elevation, 100 -year
frequency flood elevation, and graphical
- 38 -
or numerical scales (horizontal and
vertical); and
(D) A soil erosion and sedimentation control
plan for disturbed areas. This plan shall
include a description of the sequence of
grading activities and the temporary
sediment and erosion control measures
to be implemented to mitigate their effect.
This plan shall also include a description
of final stabilization and revegetation
measures, and the identification of a
responsible party to ensure post -
construction maintenance.
C. Engineering calculations and supporting data shall be submitted
showing that the proposed work will meet the criteria of
subsection B of this Section.
d. Any and all other local, state and federal permits or approvals
that maybe required for this type of development.
3. Based on the best available existing data according to the Illinois
State Water Survey's Flood Plain Information Repository, the Director
of Engineering and Community Development shall compare the elevation
of the site to the base flood or 100 -year frequency flood elevation.
a. Should no elevation information exist for the site, the
developer's engineer shall calculate the elevation according to
subsection 8-11-51) of this chapter.
b. Any development located on land that can be shown to have been
higher than the base flood elevation as of the current Flood
Insurance Rate Map identification is not in the SFHA and,
therefore, not subject to the requirements of this Ordinance.
c. The Director of Engineering & Community Development shall
maintain documentation of the existing ground elevation at the
development site and certification that this ground elevation
existed prior to the date of the site's first Flood Insurance
Rate Map identification.
4. The Director of Engineering and Community Development shall be
responsible for obtaining from the applicant copies of all other
local, state, and federal permits, approvals or permit -not -required
letters that may be required for this type of activity. The
Director of Engineering and Community Development shall not issue
the development permit unless all required local, state and federal
permits have been obtained.
- 39 -
B. Preventing increased Damages.
1. No development in the SFHA, where a floodway has not been
determined shall create a damaging or potentially damaging increase
in flood heights or velocity or threat to public health, safety and
welfare or impair the natural hydrologic and hydraulic functions of
the floodway or channel, or impair existing water quality or
aquatic habitat. Construction impacts shall be minimized by
appropriate mitigation methods as called for in this Ordinance.
2. Within all riverine SFHA's where the floodway has not been
determined, the following standards shall apply:
a. The developer shall have a Registered Professional Engineer
state in writing and show through supporting plans,
calculations, and data that the project meets the engineering
requirements of subsections 8-11-7B3a through B3L of this
chapter for the entire flood plain as calculated under the
provisions of subsection 8-11-5D of this chapter.
(1)As an alternative, the developer should have an
engineering study performed to determine a floodway
and submit that engineering study to IDNR/OWR for
acceptance as a designated floodway.
(2)Upon acceptance of their floodway by IDNR/OWR, the
developer shall then demonstrate that the project
meets the requirements of Section 8-11-7 for the
designated floodway. The floodway shall be defined
according to the definition in Section 8-11-2 of this
chapter.
b. A development permit shall not be issued unless the applicant
first obtains a permit from IDNR/OWR or written documentation
that a permit is not required from IDNR/OWR.
C. No permit from IDNR/OWR shall be required if the IDNR/OWR has
delegated permit responsibility to the Village of Elk Grove
Village per 92 Ill. Adm. Code, Part 708 for designated
floodways.
d. Permits for Dams.
(1) Any work involving the construction, modification or
removal of a dam as defined in Section 8-11-2 per 92
Ill., Adm. Code Part 702 (Rules for Construction of Dams)
shall obtain an IDNR/OWR permit or letter indicating a
permit is not required prior to the start of construction
of a dam.
(2) If the Director of Engineering and Community Development
finds a dam that does not have an IDNR/OWR permit, the
- 40 -
Director of Engineering and Community Development shall
immediately notify the IDNR/OWR Schaumburg Office.
(3) If the Director of Engineering & Community Development
finds a dam which is believed to be in unsafe condition,
the Director of Engineering & Community Development shall
immediately notify the owner of the dam, IDNR/OWR
Schaumburg Office and the Illinois Emergency Management
Agency (IEMA).
3. The following activities may be permitted without a Registered
Professional Engineer's review or calculation of a base flood
elevation and designated floodway. Such activities shall still
meet the other requirements of this Ordinance:
a) Underground and overhead utilities that:
(1) Do not result in any increase in existing ground
elevations, or
(2) Do not require the placement of above
ground structures in the floodway, or
(3) In the case of underground stream crossings, the top
of the pipe or encasement is buried a minimum of 3'
below the existing streambed, and
(4) overhead utility lines shall be constructed above the
estimated 100 -year frequency flood elevation or
attached above the low chord of an existing bridge
(with the permission of the bridge owner). No
supporting towers shall be placed in the watercourse
and shall be designed so as to not catch debris.
(5) Disturbance of streamside vegetation shall be kept to
a minimum during construction to prevent erosion and
sedimentation.
(6) A utility crossing carrying material which may cause
water pollution as defined by the Environmental
Protection Act 415 ILCS 5 (1992 State Bar Edition)
shall be provided with shut-off valves on each side of
the body of water to be crossed.
(7) All Illinois Commerce Commission, National Electric
Safety Codes, and federal requirements for clearance
must be met.
b. Storm and sanitary sewer outfalls that:
(1) Do not extend riverward or lakeward of the existing
adjacent natural bank slope, and
ifi
(2) Do not result in an increase in ground elevation, and
(3) Are designed so as not to cause stream bank erosion at
the outfall location.
C. Construction of shoreline and streambed
protection that:
(1) Does not exceed 1,000 feet in length.
(2) Materials are not placed higher than the existing top
of bank.
(3) Materials are placed so as not to reduce the cross-
sectional area of the stream channel by more than 108.
(4) Stabilization utilizing native vegetation and gradual
side slopes are the preferred mitigation methods for
existing erosion problems. Where high channel
velocities, sharp bends or wave action necessitate the
use of alternative stabilization measures, soil
bioengineering techniques, natural rock or riprap are
preferred materials. Artificial materials such as
concrete, construction rubble, and gabions should be
avoided unless there are no practicable alternatives.
d. Temporary stream crossings in which:
(1) The approach roads will be 1/2 foot or
less above natural grade.
(2) The crossing will allow stream flow to pass without
backing up the water above the stream bank vegetation
line or above any drainage tile or outfall invert.
(3) The top of the roadway fill in the channel will be at
least 21 below the top of the lowest bank. Any fill
in the channel shall be non-erosive material, such as
riprap or gravel.
(4) All disturbed stream banks will be seeded or otherwise
stabilized as soon as possible upon installation and
again upon removal of construction.
(5) The access road and temporary crossings will be
removed within one year after authorization.
e. The construction of light poles, sign posts and similar
structure;
f. The construction of sidewalks, driveways, athletic fields
(excluding fences), patios and similar surfaces which are
built at grade;
- 42 -
g. The construction of properly anchored, unwalled, open
structures such as playground equipment, pavilions, and
carports built at or below existing grade that would not
obstruct the flow of flood waters;
h. The placement of properly anchored buildings not exceeding
seventy (70) square feet in size, nor ten (10) feet in any
one dimension (e.g., animal shelters and tool sheds);
i. The construction of additions to existing buildings which
do not increase the first floor area by more than twenty
(20) percent, which are located on the upstream or
downstream side of the existing buildings, and which do
not extend beyond the sides of the existing building that
are parallel to the flow of flood waters;
j. Minor maintenance dredging of a stream channel where:
(1) The affected length of stream is less than 1,000 feet.
(2) The work is confined to reestablishing flows in
natural stream channels, or
(3) The cross-sectional area of the dredged channel
conforms to that of the natural channel upstream and
downstream of the site.
4. The flood carrying capacity within any altered or relocated
watercourse shall be maintained.
5. Compensatory Storage.
a. Whenever any portion of a floodplain is authorized for use,
the volume of space which will be occupied by the
authorized fill or structure below the base flood or 100 -
year frequency flood elevation shall be compensated for and
balanced by a hydraulically equivalent volume of excavation
taken from below the base flood or 100 -year frequency flood
elevation.
b. The excavation volume shall be at least equal to 1.5 times
the volume of storage lost due to the fill or structure.
C. In the case of streams and watercourses, such excavation
shall be made opposite or adjacent to the areas so filled
or occupied.
d. All floodplain storage lost below the existing 10 -year
flood elevation shall be replaced below the proposed 10 -
year flood elevation. All floodplain storage lost above
the existing 10 -year flood elevation shall be replaced
above the proposed 10 -year flood elevation. All such
- 43 -
excavations shall be constructed to drain freely and openly
to the watercourse.
8-11-9:
Permitting Requirements Applicable to All Floodplain Areas. In addition to
the requirements found in sections 8-11-6, 8-11-7 and 8-11-8 for
development in flood fringes, designated floodways, and SFHA or flood
plains where no floodways have been identified (Zones A, AO, AH, AE, A1 -
A30, A99, VO, V1-30, VE, V, M, E, D, or X), the following requirements
shall be met:
A. Public Health Standards:
1. No developments in the SFHA shall include locating or storing
chemicals, explosives, buoyant materials, animal wastes,
fertilizers, flammable liquids, pollutants, or other hazardous
or toxic materials below the flood protection elevation(FPE).
2. New and replacement water supply systems, wells, sanitary
sewer lines and on-site waste disposal systems may be permitted
providing all manholes or other above ground openings located
below the FPE are watertight.
B. Carrying Capacity and Notification:
1. For all projects involving channel modification, fill, or
stream maintenance (including levees), the Flood carrying
capacity of the watercourse shall be maintained.
2. In addition, the Village of Elk Grove Village shall notify
adjacent communities in writing 30 days prior to the issuance
of a permit for the alteration or relocation of the
watercourse.
C. Protecting buildings.
1. All buildings located within a 100 -year floodplain also known
as a SFHA shall be protected from flood damage below the flood
protection elevation. This building protection criteria
applies to the following situations:
a. Construction or placement of a new building.
b. A structural alteration to an existing building that
either increases the first floor area by more than 20
percent or is a substantial improvement (exceeding the
building's market value by more than 50 percent). This
alteration shall be figured cumulatively beginning with
any alteration which has taken place subsequent to April
1, 1990.
- 44
C. Installing a manufactured home on a new site or a new
manufactured home on an existing site. This building
protection requirements does not apply to returning a
mobile home to the same site it lawfully occupied before
it was removed to avoid flood damage; and
d. Installing a travel trailer on a site for more than 180
days.
This building protection requirement may be met by one of the
following methods.
2. A residential or non-residential building, when allowed, may be
constructed on permanent land fill in accordance with the
following:
a. The lowest floor, (including basement) shall be at or
above the flood protection elevation.
b. Fill Requirements.
(1) Fill shall be placed in layers no greater than one
(1) foot deep before compaction and should extend at
least ten (10) feet beyond the foundation of the
building before sloping below the flood protection
elevation.
(2) The top of the fill shall be above the flood
protection elevation. However, the ten (10) foot
minimum may be waived if a structural engineer
certifies an alternative method to protect the
building from damages due to hydrostatic pressures.
(3) The fill shall be protected against erosion and
scour.
(4) The fill shall not adversely effect the flow or
surface drainage from or onto neighboring properties.
3. A residential or non-residential building may be elevated in
accordance with the following:
a. The building or improvements shall be elevated on crawl space,
stilts, piles, walls, or other foundation that is permanently
open to flood waters and not subject to damage by hydrostatic
pressures of the base flood or 100 -year frequency flood. The
permanent openings shall be no more than one foot above
existing grade, and consists of a minimum of two openings.
The openings must have a total net area of not less than one
square inch for every one square foot of enclosed area subject
to flooding below the Base Flood Elevation.
- 45 -
b. The foundation and supporting members shall be anchored and
aligned in relation to flood flows and adjoining structures so
as to minimize exposure to known hydrodynamic forces such as
current, waves, ice and floating debris.
C. All areas below the flood protection elevation shall be
constructed of materials resistant to flood damage:
(1) The lowest floor (including basement) and all electrical,
heating, ventilating, plumbing, and air conditioning
equipment and utility meters shall be located at or above
the flood protection elevation.
(2) Water and sewer pipes electrical and telephone lines,
submersible pumps, and other waterproofed service
facilities may be located below the flood protection
elevation.
d. The area below the flood protection elevation may only be
used for the parking of vehicles, building access or storage
in an area other than a basement.
e. Manufactured homes and travel trailers to be installed on a
site for more than 180 days, shall be elevated to or above
the flood protection elevation; and, shall be anchored to
resist flotation, collapse, or lateral movement by being
tied down in accordance with the Rules and Regulations for
the Illinois Mobile Home Tie -Down Act issued pursuant to 77
Ill. Adm. Code 870. In addition, all manufactured homes
shall meet the following elevation requirements:
(1) In the case of manufactured homes placed or substantially
improved (1) outside of a manufactured home park or
subdivision, (2) in a new manufactured home park or
subdivision, (3) in an expansion to an existing
manufactured home park or subdivision, or (4) in an
existing manufactured home park or subdivision on which a
manufactured home has incurred substantial damage from a
flood, the top of the lowest floor shall be elevated to
or above the flood protection elevation.
(2) In the case of manufactured homes placed or substantially
improved in an existing manufactured home park or
subdivision, the manufactured home shall be elevated so
that either the top of the lowest floor is above the base
flood elevation or the chassis is at least 36 inches in
height above grade and supported by reinforced piers or
other foundations of equivalent strength, whichever is
less.
f. Recreational vehicles or travel trailers shall be required to
meet the elevation and anchoring requirements of Subsection 8-
11-9C3 above unless:
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(1) They are on site for fewer than 180 consecutive days; and
(2) They are fully licensed and ready for highway use. A
recreational vehicle is ready for highway use if it is on
its wheels or jacking system, is attached to the site only
by quick disconnect type utility and service devices, and
has no permanently attached additons.
4. Only a non-residential building may be structurally dry floodproofed
(in lieu of elevation) provided that:
a) A Registered Professional Engineer shall certify that the
building has been structurally dry floodproofed below the flood
protection elevation, the structure and attendant utility
facilities are watertight and capable of resisting the effects
of the base flood or 100 -year frequency flood.
b) The building design shall take into account flood velocities,
duration, rate of rise, hydrostatic and hydrodynamic forces,
the effects of buoyancy, and impacts from debris or ice.
c) Floodproofing measures shall be operable without human
intervention and without an outside source of electricity
(Levees, berms, floodwalls and similar works are not considered
floodproofing for the purpose of this subsection).
S. Tool sheds and detached garages on an existing single-family platted
lot, may be constructed with the lowest floor below the flood
protection elevation in accordance with the following:
a) The building is not used for human habitation.
b) All areas below the base floor or 100 -year frequency flood
elevation shall be constructed with waterproof material.
Structures located in a designated floodway shall be
constructed and placed on a building site so as not to block
the flow of floodwaters and shall also meet the Appropriate Use
criteria of Section 6-11-7. In addition, all other
requirements of Section 8-11-6, 8-11-7 and 8-11-8 must be met.
c) The structure shall be anchored to prevent flotation.
d) Service facilities such as electrical and heating equipment
shall be elevated or floodproofed to the flood protection
elevation.
e) The building shall be valued at less than $7,500 and be less
than 500 square feet in floor size.
f) The building shall be used only for the storage of vehicles or
tools and may not contain other rooms, workshops, greenhouses
or similar uses.
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g) The building shall meet the permanent opening criteria of
Section 8-11-9C3a.
6. Existing buildings located within a designated floodway shall also
meet the more restrictive Appropriate Use standards included in
Section 8-11-7. Non -conforming structures located in a designated
floodway may remain in use, but may not be enlarged, replaced or
structurally altered in accordance with Section 8-117B of this
chapter. A non -conforming structure damaged by flood, fire, wind
or other natural or made -made disaster may be restored unless the
damage exceeds fifty percent (508) of its market value before it
was damaged, in which case it shall conform to this Ordinance.
8-11-10:
OTHER DEVELOPMENT REQUIREMENTS: The President and Board of Trustees shall
take into account flood hazards, to the extent that they are known in all
official actions related to land management, use and development.
A. New subdivisions, manufactured home parks, annexation agreements, and
Planned Unit Developments (PUD's) within the SFHA shall be reviewed to
assure that the proposed developments are consistent with Sections 8-
11-6, 8-11-7, 8-11-8 and 8-11-9 of this chapter and the need to
minimize flood damage. Plats or plans for new subdivisions, mobile home
parks and Planned Unit Developments (PUD's)shall include a signed
statement by a Registered Professional Engineer that the plat or plans
account for changes in the drainage of surface waters in accordance
with the Plat Act (765 ILCS 205/2).
B. Proposals for new subdivisions, manufactured home parks, travel trailer
parks, Planned Unit Developments (PUD's) and additions to manufactured
home parks and additions to subdivisions shall include base flood or
100 -year frequency flood elevation data and floodway delineations.
1.Where this information is not available from an existing study filed
with the Illinois State water Survey, the applicant's engineer shall
be responsible for calculating the base flood or 100 -year frequency
flood elevation per subsection 8-11-5D of this chapter and the
floodway delineation per the definition in Section 8-11-2.
2.The applicant's engineer shall submit the data to IDNR/OWR for review
and approval as best available regulatory data and then send it to
the State Water Survey.
C. Streets, blocks, lots, parks and other public grounds shall be located
and laid out in such a manner as to preserve and utilize natural
streams and channels. Wherever possible, the flood plains
shall be included within parks or other public grounds.
D. The President and Board of Trustees shall not approve any Planned Unit
Development (PUD) or plat of subdivision located outside the corporate
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limits unless such agreement or plat is in accordance with the
provisions of this Ordinance.
8-11-11:
VARIANCES: No variances shall be granted to any development located in a
designated floodway as defined in Section 8-11-2 of this chapter. Whenever
the standards of this ordinance place undue hardship on a specific
development proposal, the applicant may apply to the Department of
Engineering and Community Development for a variance. The Department of
Engineering and Community Development shall review the applicant's request
for a variance and shall submit its recommendation to the President and
Board of Trustees.
A. No variance shall be granted unless the applicant demonstrates that:
1. The development activity cannot be located
outside the SFHA;
2. An exceptional hardship would result if the
variance were not granted;
3. The relief requested is the minimum necessary;
4. There will be no additional threat to public
health, safety, beneficial stream uses and
functions, especially aquatic habitat, or
creation of a nuisance;
S. There will be no additional public expense
for flood protection, lost environmental
stream uses and functions, rescue or relief
operations, policing, or repairs to stream
beds and banks, roads, utilities, or other
public facilities;
6. The provisions of Sections 8-11-6B and 8-11-8B of
this chapter shall still be met;
7. The activity is not in a designated floodway;
6. The applicant's circumstances are unique and
do not represent a general problem, and
9. The granting of the variance will not alter
the essential character of the area involved
including existing stream uses.
B. The Director of Engineering and Community Development shall notify an
applicant in writing that a variance from the requirements of Section
8-11-9 that would lessen the degree of protection
to a building will:
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1. Result in increased premium rates for flood
insurance up to amounts as high as $25 for
$100 of insurance coverage;
2. Increase the risks to life and property; and
3. Require that the applicant proceeds with knowledge of these
risks and that he will acknowledge in writing that he assumes
the risk and liability.
C. Variances requested in connection with restoration of a historic site
or historic structure as defined in Section 8-11-2 "Historic
Structures", may be granted using criteria more permissive than the
requirements of Sections 8-11-11A and B of this Section subject to the
conditions that:
1. The repair or rehabilitation is the minimum necessary to
preserve the historic character and design of the structure,
and,
2. The repair or rehabilitation will not result in the structure
being removed as a certified historic structure.
8-11-12:
DISCLAIMER OF LIABILITY:
A. The degree of flood protection required by this Ordinance is considered
reasonable for regulatory purposes and is based on available information
derived from engineering and scientific methods of study.
B. Larger floods may occur or flood heights may be increased by man-made or
natural causes.
C. This Ordinance does not imply that development, either inside or outside
of the SFHA, will be free from flooding or damage.
D. This Ordinance does not create liability on the part of the Village of
Elk Grove village or any officer or employee thereof for any flood
damage that results from reliance on this Ordinance or any
administrative decision made lawfully thereunder.
8-11-13:
PENALTY: Failure to comply with the requirements of a permit or conditions
of a variance resolution shall be deemed to be a violation of this
Ordinance. Upon due investigation, the Director of Engineering and
Community Development may determine that a violation of the minimum
standards of this Ordinance exist. The Director of Engineering and
Community Development shall notify the owner in writing of such violation.
A. If such owner fails after ten days notice to correct the violation:
X111=
1. The Village of Elk Grove Village may make application to the Circuit
Court for an injunction requiring conformance with this Ordinance or
make such other order as the Court deems necessary to secure
compliance with this Ordinance.
2. Any person who violates this ordinance shall, upon conviction
thereof, be fined not less than fifty dollars (50.00) or more than
one -thousand dollars ($1,000.00) for each offense.
3. A separate offense shall be deemed committed upon each day during or
on which a violation occurs or continues.
4. The Village of Elk Grove Village may record a notice of violation on
the title to the property.
B. The Director of Engineering and Community Development shall inform the
owner that any such violation is considered a willful act to increase
flood damages and, therefore, may cause coverage by a Standard Flood
Insurance Policy to be suspended.
1. The Director of Engineering & Community Development is authorized to
issue an order requiring the suspension of the subject development.
The stop -work order shall be in writing, shall indicate the reason
for the issuance, and shall order the action, if necessary, to
resolve the circumstances requiring the stop -work order. The stop -
work order constitutes a suspension of the permit.
2. No site development permit shall be permanently suspended or revoked
until a hearing is held by the (Board of Appeals). Written notice of
such hearing shall be served on the permittee and shall state: (1)
the grounds for compliant or reasons for suspension or revocation;
and (2) the time and place of the hearing. At such hearing, the
permittee shall be given an opportunity to present evidence on
his/her behalf. At the conclusion of the hearing, the (Board of
Appeals) shall determine whether the permit shall be suspended or
revoked.
C. Nothing herein shall prevent the Village of Elk Grove Village from
taking such other lawful action to prevent or remedy any violations.
All costs connected therewith shall accrue to the person or persons
responsible.
8-11-14
ABROGATION AND GREATER RESTRICTIONS:
A. This Ordinance is not intended to repeal, abrogate or impair any
existing easements, covenants, or deed restrictions.
B. Where this Ordinance and other ordinance, easements, covenants, or deed
restrictions conflict or overlap, whichever imposes the more
stringent restrictions shall prevail.
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C. This ordinance is intended to repeal the original ordinance or
resolution which was adopted to meet the National Flood Insurance
Program regulations, but is not intended to repeal the resolution which
the Village of Elk Grove Village passed in order to establish initial
eligibility for the program.
8-11-15
SEPARABILITY: The provisions and sections of this ordinance shall be deemed
separable and the invalidity of any portion of this ordinance shall not
affect the validity of the remainder.
Section 3: That the village Clerk is hereby authorized to publish this
Ordinance in Pamphlet Form.
EFFECTIVE DATE: That this ordinance shall be in full force and effect from
and after its passage and approval and publication as required by law.
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VOTE:
AYE:
6
NAY:
0 ABSENT: 0
PASSED
this
24th
day of
October 2000.
APPROVED
this
24th
day of
October 2000.
Craig B. Johnson
Mayor
ATTEST:
Ann I. Walsh
Village Clerk
PUBLISHED this 27th day of October , 2000, in pamphlet form.
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