HomeMy WebLinkAboutORDINANCES-1989-099-O-89•• W•
AN ORDINANCE
DELETING EXISTING TITLE 4, CHAPTER 16 OF THE CITY
CODE AND ENACTING A NEW TITLE 4, CHAPTER 16,
TITLED "REGULATING DEVELOPMENT IN SPECIAL
FLOOD HAZARD AREAS"
• WHEREAS, the City must enact an ordinance meeting the
minimum requirements of the Federal Emergency Management Agency
in order to maintain its eligibility in the National Flood
Insurance Program; and
WHEREAS, the City must enact an ordinance meeting the
requirements of the Illinois Department of Transportation,
Division of Water Resources, concerning development affecting
floodways; and
NOW, THEREFORE, BE IT ORDAINED BY THE CITY COUNCIL OF
THE CITY OF EVANSTON, COOK COUNTY, ILLINOIS:
SECTION 1: That existing, Title 4, Chapter 16 of
the City Code, "Development in Flood
Hazard Areas", be deleted in its entirety, and replaced by a new
•
Title
4, Chapter 16, "Regulating
Development in Special Flood
Plain
Areas", reading
as follows:
4-16-1 PURPOSE: This Ordinance is enacted pursuant to the
police powers granted to the City of Evanston by Ill. Rev.
Stat., (1987) Chapter 24, sections 1-2-1, 11-12-12, 11-30-2, 11-
30-8, and 11-31-2, in order to accomplish the following
purposes:
(A) To prevent unwise developments from :increasing the flood or
drainage hazards to others;
(B) To meet the requirements of Chapter 19, paragraph 52 et seq.
of the Ill. Rev. Stat., "An Act in Relation to the
Regulation of the Rivers, Lakes and Streams of the State of
Illinois," approved June 10, 1911, as amended.
(C) To assure that new development does not increase the flood
• or drainage hazards to others, or creating unstable
conditions susceptible to erosion;
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(D) To protect new buildings and major improvements to buildings
from flood damage;
(E) To protect human life and health from the hazards of
flooding;
(F) 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
(G) To make federally -subsidized flood insurance available for
property in the City, by fulfilling the requirements of the
National Flood Insurance Program.
(H) To comply with the rules and regulations of the National
Flood Insurance Program codified as 44 CFR 59-79, as
amended.
4-16-2 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", Ill.
Rev. Stat. 1987, ch. 19, par. 52 et seq.
•
"Applicant":
Any person, firm, corporation or agency
which submits an application.
"Appropriate Use":
Only uses of the regulatory floodway
that are permissible and will be
considered for permit issuance. The
only uses that will be allowed are as
specified in Section 4-16-8.
"Base Flood":
The flood having a one -percent •
probability of being equalled or exceeded in any given
year. The base flood is also known as the 100- year
K
frequency flood event. Application of the base flood
elevation at any location is as defined in Section 4-
16-5 of this Ordinance.
"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.
"Compensatory Storage":
An artificially excavated, hydraulically equivalent
volume of storage within the SFHA used to balance the
loss of natural flood storage within the flood plain.
The uncompensated loss of natural flood plain storage
can increase off -site flood water elevations and flows.
• "Conditional Approval of a Regulatory Floodway Map
Change":
Preconstruction approval by DWR and the
Federal Emergency Management Agency of a
proposed change to the floodway map. This
preconstruction 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 (CLOMAR)": '
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
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Hazard Boundary Map or Flood Insurance Rate Map, once
the as -built plans are submitted and approved.
"Dam":
All obstructions, wall embankments or barriers,
together with their abutments and appurtenant works,
any, constructed for the purpose of storing or
diverting water or creating a pool. Underground water
storage tanks are not included.
"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.
(c) Drilling, mining, installing utilities,
construction of roads, bridges, or similar
projects.
(d) Construction or erection of levees,
walls, fences, dams, or culverts;
channel modification; filling, dredging,
grading, excavating, paving, or other
non-agricultural alterations of the
ground surface; storage of materials;
deposit of solid or liquid waste; •
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(e) 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, or similar agricultural practices that
do not involve filling, grading, or construction of levees.
"DWR":
Illinois Department of Transportation, Division of
Water Resources.
"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.
"Exempt Organization":
Organizations which are exempt from this Ordinance
per the Ill. Rev. Stat.including state, federal or
local units of government.
"FEMA":
Federal Emergency Management Agency and its
regulations at 44 CFR 59-79 effective as of October 1,
1986. This incorporation does not include any later
editions or amendments.
"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
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rapid accumulation or runoff of surface waters from
any source.
"Flood Fringe":
That portion of the flood plain outside of the
regulatory 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 flood plains and may or may
not depict floodways.
"Flood Plain":
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. Flood
plains may also include detached Special Flood Hazard
Areas, ponding areas, etc. The flood plain is also •
known as the Special Flood Hazard Area (SFHA). The
flood plains are those lands within the jurisdiction
of the City, that are subject to inundation by the
base flood or 100-year frequency flood. The SFHA's of
the City are generally identified as such on the
Flood Insurance Rate Map of the City, prepared by the
Federal Emergency Management Agency (or the U.S.
Department of Housing and Urban Development) and dated
November 26, 1982. The SFHA's of the City are
designated as the shores of Lake Michigan and the
shores of the Chicago Water Reclamation District
Channel.
"Floodproofing" :
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•
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.
"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, unknown localized
conditions, wave actions and unpredictable effects
such as those caused by ice or debris jams.
"Hydrologic and Hydraulic Calculations":
Engineering analyses which determine expected flood
flows and flood elevations based on land
characteristics and rainfall events.
"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 or FIRM. I
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"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.
E
"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
connected to the required utilities. The term
manufactured homes also includes park trailers, travel
trailers and other similar vehicles placed on -site for
more than 180 consecutive days.
"Manufactured Home Park or Subdivision":
A parcel (or contiguous parcels) of land divided into
two or more manufactured home lots for rent or sale.
•
"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.
"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
A
flood control project by persons or parties who are
not public agencies.
"Publicly Navigable Waters":
All streams and lakes capable of being navigated by
• watercraft.
"Registered Land Surveyor":
A land surveyor registered in the State of Illinois,
under The Illinois Land Surveyors Act (Ill. Rev. Stat.
1987, ch. 111, pars. 3201-3234).
"Registered Professional Engineer":
An engineer registered in the State of Illinois, under
The Illinois Professional Engineering Act (Ill. Rev.
Stat. 1987, ch.111, pars. 5101-5137).
"Regulatory Floodway":
The channel, including on -stream lakes, and that
portion of the flood plain adjacent to a stream or
watercourse as designated by DWR, which is needed to
store and convey the existing and anticipated future
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% increase
in velocities. Where interpretation is needed to
determine the exact location of the regulatory floodway
boundary, the Division should be contacted for the
interpretation.
"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.
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"Riverine SFHA":
Any SFHA subject to flooding from a river, creek,
intermittent steam, ditch, on -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.
"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, or E.
"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 trailer on a
site for more than 180 days.
"Substantial Improvement":
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,
(a) before the improvement or repair is started, or (b)
if the structure has been damaged, and is being
restored, before the damage occurred. For the purposes
of this definition "substantial improvement" is
considered to occur when the first alteration of any
wall, ceiling, floor or other structural part of the
building commences, whether or not that alteration
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affects the external dimensions of the structure. The
term does not, however, include either (1) any project
for improvement of a structure to comply with existing
state or local health, sanitary, or safety code
specifications which are solely necessary to assure
• safe living conditions or (2) any alteration of a
structure listed on the National Register of Historic
Places or a State Inventory of Historic Places.
"Transition Section":
Reaches of the stream or floodway where water flows
from a narrow cross-section to a wide cross-section or vice
versa.
Section 4-16-3: HOW TO USE THIS ORDINANCE
The Director of Building and
Zoning shall be responsible for fulfilling all of the duties
listed in Section 4-16-4.
• To fulfill those duties, the Director of Building and Zoning
first should use the criteria listed in Section 4-16-5 Base
Flood Elevations, to determine whether the development site is
located within a floodplan. Once it has been determined that a
site is located within a flood plain, the Director of Building
and Zoning must determine whether the development site is within
a flood fringe, a regulatory floodway, or within a SFHA or floor
plain on which no floodway has been identified. If the site is
within a flood fringe, the Director of Building and Zoning shall
require that the minimum requirement of Section 4-16-6 be that
if the site is within a floodway, the Director of Building and
Zoning shall require that the minimum requirement of Section 4-
16-7 be met. If the site is located within a SFHA or flood
plain for which no detailed study has been completed and
approved, the Director of Building and Zoning shall require that
the minimum requirements of Section 4-16-8 be met.
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In addition, the general requirement of Section 4-16-9 shall be
met for all developments meeting the requirements of Section 4-
16-6, 4-16-7, or 4-16-8. The Director of Building and Zoning
shall assure that all subdivision proposals shall meet the
requirements of Section 4-16-12.
•
If a variance is to be granted for a proposal, the Director of
Building and Zoning shall review the requirements of Section 4-
6-16 to make sure they are met. In addition, the Director of
Building and Zoning shall complete all notification
requirements.
In order to assure that property owners obtain permits as
required in this Ordinance, the Director of Building and Zoning
shall complete all notification requirements.
In order to assure that property owners obtain permits as
required in this Ordinance, the Director of Building and Zoning
may take any and all actions as outlined in Section 4-16-15. •
Section 4-16-4 DUTIES OF THE ENFORCEMENT
OFFICIAL(S): The Director of
Building and Zoning shall be responsible for the general
administration and enforcement of this Ordinance which shall
include the following:
Section 4-16-4-1: Determining the Flood Plain Designation.
Check all new development sites to determine
whether they are in a Special Flood Hazard Area (SFHA). If they
are in a SFHA, determine whether they are in a floodway, flood
fringe or in a flood plain on which a detailed study has not
been conducted which drains more than one (1) square mile.
0
Section 4-16-4-2: Professional Engineer Review.
If the development site is
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within a floodway or in a flood plain on which a detailed study
has not been conducted 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
City for review to ensure that the development meets the
• requirements of Section 4-16-7. In the case of an Appropriate
Use, the P.E. shall state in writing that the development meets
the requirements of Section 4-16-7.
Section 4-16-4-3: Dam Safety Requirements.
Ensure that a DWR Dam Safety
permit is required, if the proposed development activity
includes construction of a dam as defined in Section 4-16-2.
Regulated dams may include weirs, restrictive culverts or
impoundment structures.
Section 4-16-4-4: Other permit requirements.
Ensure that any and all
required federal, state and local permits are received prior to
• the issuance of a flood plain development permit.
Section 4-16-4-5: Plan Review and Permit
Issuance. Ensure that
all development activities within the SFHAs of the jurisdiction
of the City, meet the requirements of this Ordinance and issue a
flood plain development permit in accordance with the provisions
of this Ordinance and other regulations of this community when
the development meets the conditions of this Ordinance.
Section 4-16-4-6: Inspection Review. Inspect
all development projects before,
during and after construction to assure proper elevation of the
. structure and to ensure they comply with the provisions of this
Ordinance.
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Section 4-16-4-7: Elevation and Floodproofing
Certificates. Maintain in the
permit files an Elevation Certificate certifying the elevation
of the lowest floor (including basement) of a residential or
non-residential building or the elevation to which a non-
residential building has been
floodproofed,
using a
•
Floodproofing Certificate, for
all buildings
subject
to Section
4-16-9 of this Ordinance for public inspection and provide
copies of same;
Section 4-16-4-8: 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 or elevation and
floodproofing certificates for all buildings constructed subject
to this Ordinance.
•
Section 4-16-4-9: State Permits. Ensure that
construction authorization has
been granted by the Illinois Division of Water Resources, for
all development projects subject to Section 4-16-7 and 4-16-8 of
this Ordinance, unless enforcement responsibility has been
delegated to the City. Upon acceptance of this Ordinance by DWR
and FEMA, responsibility is hereby delegated to the City as per
92 Ill. Adm. Code 708 for construction in the regulatory
floodway and flood plain when floodways have not been defined in
Sections 4-16-7 and 4-16-8 of this Ordinance. However, the
following review approvals are not delegated to the City and
shall require review or permits from DWR:
a. Organizations which are exempt from this •
Ordinance, as per the Illinois Revised Statutes;
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b. Department of Transportation projects, dams or
impoundment structures as defined in Section 4-16-
2 and all other state, federal or local unit of
government projects, including projects of the
City and County, except for those projects meeting
• the requirement of Section 4-16-7-5;
C. 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
Section 4-16-7-1(e);
d. An engineer's analysis of the flood profile due to
Section 4-16-7-1(d);
e. Alternative transition sections and hydraulically
equivalent compensatory storage as indicated in Section
4-16-7-1 (a) , (b) , and (h) .
f. Permit issuance of structures within or over publicly
navigable rivers, lakes, and streams;
g. Any changes in the Base Flood Elevation or floodway
locations; and,
• h. Base Flood Elevation determinations where none now
exist.
Section 4-16-4-10: Cooperation with Other
Agencies. Cooperate with state
and federal flood plain management agencies to improve base
flood or 100-year frequency flood and floodway data and to
improve the administration of this Ordinance. Submit data to
DWR and the Federal Emergency Management Agency (FEMA) for
proposed revisions of a regulatory map. Submit reports as
required for the National Flood Insurance Program. Notify FEMA
of any proposed amendments to this Ordinance.
• Section 4-16-4-11: Promulgate Regulations.
Promulgate rules and
regulations as necessary to administer and enforce the
15
provisions of this Ordinance, subject however to the review and
approval of DWR and FEMA for any Ordinance changes.
Section 4-16-5: Base Flood Elevation. This
Ordinance's protection -
standard is based on the Flood Insurance Study for the City.
a base flood elevation or 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. 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 DWR
and FEMA.
Section 4-16-5-1: The base flood or 100-year
frequency flood elevation for
each of the remaining SFHAs delineated as an "A Zone" on the
Flood Insurance Rate Map of the City shall be according to the
best existing data available in the Illinois State Water Survey*
Flood Plain Information Repository. When no base flood or 100-
year frequency flood elevation exists, the base flood or 100-
year frequency food elevation for a riverine SFHA, shall be
determined from a backwater model, such as HEC-11, WSP-2, or a
dynamic model such as HIP. 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. Flood flows should be based
on anticipated future land use conditions in the watershed as
determined from adopted local and regional land use plans.
Along any watercourses draining more than one (1) square mile,
the above analysis shall be submitted to DWR for approval; once•
approved it must be submitted to the Illinois State Water Survey
Floodplain Information Repository for filing. For a non-
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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 the Illinois State Water
Survey.
0 Section 4-16-6: 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 provisions of this
Ordinance are met. No use will be permitted which adversely
affects the capacity of drainage facilities or systems.
Developments located within the flood fringe shall meet the
requirements of this section, along with the requirements of
Section 4-16-9.
Section 4-16-6-1: Development Permit. 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 Building and Zoning.
Section 4-16-6-2: Application for a development
permit shall be made on a form
provided by the Director of Building and Zoning. 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. 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
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development will be subject to the requirements of Section 4-16-
9 of this Ordinance.
Section 4-16-6-3: Upon receipt of a development
permit.application, the
Director of Building and Zoning shall compare the elevation o0
the site to the base flood or 100-year frequency flood
elevation. Any development located on land that can be shown to
have been higher than the base flood elevation as of the site's
first Flood Insurance Rate Map identification is not in the SFHA
and, therefore, not subject to the requirements of this
Ordinance. The Building Official 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 I-nsurance Rate Map
identification.
Section 4-16-6-4: The Director of Building and
Zoning 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 Building and Zoning shall not issue a permit unless
all other local, state and federal permits have been obtained.
Section 4-16-6-5: Preventing Increased Damages.
No development in the flood
fringe shall create a threat to public health and safety.
Section 4-16-6-6: 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
(LOMR) from FEMA for the purpose of removing the site from th�
flood plain.
,$
•
•
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Section 4-16-6-7: Compensatory Storage. Whenever
any portion of a flood plain
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. The excavation volume shall be
at least equal to 1.5 times the volume of storage lost due to
the fill or structure. In the case of streams and watercourses,
such excavation shall be made opposite or adjacent to the areas
so filled or occupied. All flood plain storage lost below the
existing ten-year flood elevation shall be replaced below the
proposed ten-year flood elevation. All such excavations shall
be constructed to drain freely and openly to the watercourse.
Section 4-16-7: Occupation and Use of
Identified Floodways. This
section applies to proposed development, redevelopment, site
modification or building modification within a regulatory
floodway. The Regulatory Floor Plan is defined in 4-16-2. 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 purpose of the project.
The development shall also meet the requirements of Section 4-
16-9.
Section 4-16-7-1: Development Permit. No person,
firm, corporation or govern-
mental body not exempted by state law shall commence any
development in a floodway without first obtaining a development
permit from the Director of Building and Zoning.
Section 4-16-7-2:
Application for a development
permit shall be made on a
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form provided by the Director of Building and Zoning. 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 regulatory 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;
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
lines, names of roads in the vicinity of the
site, graphic or numerical scale, and north
arrow;
(11) A plan view of the project and engineering •
study reach showing existing and proposed
conditions including principal dimensions of
PO
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
0 navigation channel (when the proposed
construction is near a commercially navigable
body of water), regulatory floodway limit,
flood plain limit, location and orientation
of cross-section, north arrow, and a graphic
or numerical scale;
(111) Cross-section views of the project and
engineering study reach showing existing plan
proposed conditions including principal
dimensions of the work as shown in plan
view, existing and proposed elevations,
normal water elevation, ten-year frequency
flood elevation, 100-year frequency flood
• elevation, and graphic or numerical scales
(horizontal and vertical);
(IV) A copy of the regulatory floodway map, marked
to reflect any proposed change in the
regulatory 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 data shall
be submitted showing that the proposed work will
meet the permit criteria of Section 4-16-8.
o. If the regulatory 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 DWR has indicated
conditional approval of the regulatory floodway
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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
4-16-9 of this Ordinance.
Section 4-16-7-3: The Director of Building
and Zoning 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. The Director of Building
and Zoning shall not issue the development permit unless all
required federal and state permits have been obtained. A
Registered Professional Engineer, under the employ or contract
of the City, shall review and approve applications reviewed
under this Section.
Section 4-16-8: Preventing Increased Damages and
a List of Appropriate Uses. The
only developments 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 •
public health and safety and welfare. Only those Appropriate
Uses listed in 92 Ill. Adm. Code 708 will be allowed.
22
Appropriate uses do not include the construction or placement of
any new structures, fill, building additions, buildings on
stilts, 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 outfalls;
d. Underground and overhead utilities;
e. Recreational facilities such as playing field 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;
f. Detached garages, storage sheds, or other non -
habitable accessory structures without toilet
facilities to existing buildings that will not
block flood flows, nor reduce floodway storage;
g. Bridges, culverts, roadways, sidewalks, railways,
runways and taxiways and any modification thereto;
h. Parking lots and any modifications thereto (where
depth of flooding at the 100 year -frequency flood
event will not exceed 1.0') and aircraft parking
• aprons built at or below ground elevation;
i. Regulatory floodway regrading, without fill, to
23
create a positive non -erosive slope toward a
watercourse.
j. Flood -proofing 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. In the case of damaged or replacement buildings,
reconstruction or repairs made to a building that
are valued at less than 50% of the market value
of the building before it was damaged or replaced,
and which do not increase the outside dimensions
of the building.
1. Additions to existing buildings above the BFE that
do not increase the building's foot print and a�
valued at less than 50% of the market value of the
building.
Section 4-16-8-1: Within the regulatory floodway
as identified on the regulatory
floodway maps designated by DWR, the construction of an
Appropriate Use will be considered permissible
provided that the proposed project meets the following
engineering 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 4-16-9 of
this Ordinance. •
a. Preservation of Flood Conveyance, so as Not
to Increase Flood Stages Upstream. For
24
•
Ll
•
Appropriate Uses other than bridge or culvert
crossings, on -stream structures or dams, all
effective regulatory 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.regulatory floodway conveyance, the
following factors shall be taken into
consideration:
(1) Regulatory floodway conveyance,
2/3
"K" = 1.486 AR
n
where "n" is Manning's roughness factor,
"A" is the effective area of the cross-
section, and "R" is the ratio of the
area to the wetted perimeter.)
(11) 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.
(111) Transition sections shall be provided
and used in calculations of effective
regulatory floodway conveyance. The
following expansion and contraction
ratios shall be used unless an
applicant's engineer can prove to DWR
through engineering calculations or
model tests that more abrupt transitions
may be used with the same efficiency:
25
(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
1. (See Open Channel Hydraulics, Ven Te Chow, 1959, McGraw-Hill
Book Company, New York.
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 length.
(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 contra-
tions and when meeting the regula-
ory floodway delineation on adja-
cent properties.
(e) All cross -sections used in the
calculations shall be located
perpendicular to flood flows.
b. Preservation of Floodway Storage so as Not •
Increase Downstream Flooding. Compensatory
storage shall be provided for any regulatory
92
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. Compensatory storage for
fill or structures shall be equal to at least
• the volume of flood plain storage lost.
Artificially created storage lost due to a
reduction in head loss behind a bridge shall
not be required to be replaced. The
compensatory regulatory floodway storage
shall be placed between the proposed normal
water elevation and the proposed 100-year
flood elevation. All regulatory floodway
storage lost below the existing ten-year
flood elevation shall be replaced below the
proposed ten-year flood elevation. All
regulatory floodway storage lost above the
existing ten-year flood elevation shall be
replaced above the proposed ten-year flood
elevation. All such excavations shall be
constructed to drain freely and openly to the
watercourse. If the compensatory storage
will not be placed at the location of the
proposed construction, the applicant's
engineer shall demonstrate to DWR through a
determination of flood discharges and water
surface elevations that the compensatory
storage is hydraulically equivalent.
Finally, there shall be no reduction in
floodway surface area as a result of a
floodway modification, unless such
modification is necessary to reduce flooding
iat an existing structure.
C. Preservation of Floodway Velocities so as Not
to Increase Stream Erosion or Flood Heights.
27
For all Appropriate Uses, except bridges or
culverts or on -stream structures, the pro-
posed work will not result in an increase in
the average channel or regulatory floodway
velocities. However, in the case of bridges
or culverts or on -stream structures built
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 rip -rap or other design measures.
d. Construction of New Bridges or Culvert
Crossing and Roadway Approaches. 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 wit
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. If the
proposed construction will increase upstream
flood stages greater than 0.1 feet, the
developer must contact DWR, Dam Safety
Section for a Dam Safety permit or waiver.
(1) The engineering analysis of
upstream floodstages must be
calculated using the flood study
flows, and corresponding flood
elevations for tailwater conditi�
for the flood study specified in
Section 4-16-5 of this Ordinance.
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 Adminis-
• tation Hydraulics of Bridge Water-
ways calculation procedures.
(11) Lost floodway storage must be
compensated for per Section 4-16-8-
-1 (b) .
(111) Velocity increases must be miti-
gated per Section 4-16-8-1(c)
(iv) If the crossing is proposed over a
public water that is used for
recreational or commercial
navigation, a Department of
Transportation permit must be
received.
(v) The hydraulic analysis for the
is backwater caused by the bridge
showing the existing condition and
proposed regulatory profile must be
submitted to DWR for concurrence
that a CLOMR is not required by
Section 4-16-8.
(vi) All excavations for the construc-
tion of the crossing shall be
designed per Section 4-16-8-1(h).
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
29
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. •
(11) 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.
(111) The determination as to whether or
not the existing crossing is a
source of flood damage and should
therefore be redesigned must be
prepared in accordance with the
Department of Transportation Rules
92 Ill. Adm. Code 708 (Floodway
Construction in Northeastern
Illinois) and submitted to the
Division for review and
concurrence before a permit is
issued.
f. On -Stream Structures Built for the
Purpose of Backing Up Water. Any
increase in upstream flood stages
greater than 0.0 foot, when compared
the existing conditions, for all flood
events up to and including the 100-year
30
n
LJ
n
U
•
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. A permit or letter
indicating a permit is not required must
be obtained from DWR, Dam Safety
Section, for a Dam Safety permit or
waiver for any structure built for the
purpose of backing up water in the
stream during normal or flood flow. All
dams and impoundment structures as
defined in Section 4-16-2 shall meet the
permitting requirements of 92 Ill. Adm.
Code 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
than:
(1) The impoundment is determined to be
in the public interest by providing
flood control, public recreation,
or regional stormwater detention;
(11) 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;
(111) The impoundment will not cause or
contribute to degraded water
quality or habitat conditions.
31
Impoundment design should include
gradual bank slopes, appropriate
bank stabilization measures, and a
pre -sedimentation basin.
(iv) 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 coordinate with
upstream municipalities to ensure
comprehensive watershed control;
(v) The project otherwise complies with
the requirements of Section 4-16-7.
g. Flood -Proofing of Existing Habitable, •
Residential and Commercial Structures. 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
ten feet from the outside of the building.
Compensation of lost storage and conveyance
will not be required for floodproofing
activities.
h. Excavation in the Floodway. 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
convenience for other Appropriate Uses,
32
transition sections shall be provided for the
excavation. The following expansion and
contraction ratios shall be used unless an
applicant's engineer can prove to DWR through
engineering calculations or model tests that
• more abrupt transitions may be used with the
same efficiency:
(1) 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;
(11) 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; and
• (111) 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.
(iv) Erosion/scour protection shall be
provided inland upstream and downstream
of the transition sections.
i. Seeding and Stabilization Plan. For all
activities located in a floodway, a seeding
and stabilization plan shall be submitted by
the applicant.
j. Public Flood Control Projects. For public
is
flood control
projects, the
permitting
requirements
of this section
will be
considered met if the applicant can
33
demonstrate to DWR 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.
k. General Criteria for Analysis of Flood
Elevations.
(1) The flood profiles, flows and floodway
data in the regulatory floodway study,
referenced in Section 4-16-5, must be
used for analysis of the base
conditions. If the study data appear to
be in error or conditions have changed,
DWR shall be contacted for approval and
concurrence on the appropriate base
conditions data to use.
(11) If the 100-year regulatory 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 the
requirements of this section for the
100-year frequency flood elevations of
the regulatory floodway conditions and
conditions with the receiving stream at
normal water elevations.
(111) If the applicant learns from DWR, .Local
governments, or a private owner that a
downstream restrictive bridge or culvert
is scheduled to be removed, reconstru�
ted, modified, or a regional flood
control project is scheduled to be
34
built, removed, constructed or modified
within the next five years, the proposed
construction shall be analyzed and shown
to meet the requirements of this section
for both the existing conditions and the
. expected flood profile conditions when
the bridge, culvert or flood control
project is built.
1. Conditional Letter of Map Revision. If the
Appropriate Use would result in a change in
the regulatory floodway location or the 100-
year frequency flood elevation, the applicant
shall submit to DWR and to FEMA all the
information, calculations, and documents
necessary to be issued a.conditional
regulatory floodway map revision and receive
from DWR a conditional approval of the
regulatory floodway change before a permit is
issued. However, the final regulatory
• floodway map will not be changed by DWR until
as -built plans or record drawings are
submitted and accepted by FEMA and DWR. In
the case of non -government projects, the
municipality in incorporated areas and the
county in unincorporated areas shall concur
with the proposed conditional regulatory
floodway map revision before DWR approval can
be given. No filling, grading, dredging or
excavating shall take place until a
conditional approval is issued. No further
development activities shall take place until
a final LOMR is issued by FEMA and DWR.
• M. Professional Engineer's Supervision. All
engineering analyses shall be performed by or
35
under the supervision of a registered
professional engineer.
n. 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 hiqh water
mark of the channel.
(11) Where it is impossible to protect
this buffer strip during
construction of an Appropriate Use,
a vegetated buffer strip shall be
established upon completion of
construction.
(111) The use of native riparian
vegetation is preferred in the
buffer strip. Access through this
buffer strip shall be provided, "
when necessary, for stream main- •
tenance purposes.
After receipt of conditional approval of
the regulatory floodway change and
issuance of a permit and a Conditional
LOMR, construction as necessary to
change the regulatory floodway
designation may proceed but no building
or structures or other construction that
is not an Appropriate Use may be placed
in that area until the regulatory
floodway map is changed and a final
LOMR is received. The regulatory
floodway map will be revised upon •
acceptance and concurrence by DWR and
FEMA of the "as- built" plans.
36
Section 4-16-8-2: State Review. For those
projects listed below located
in a regulatory floodway, the following criteria shall be
submitted to DWR for their review and concurrence prior to the
issuance of a permit:
• a. DWR will review an engineer's analysis of the
flood profile due to a proposed bridge
pursuant to Section 4-16-8-1(d).
b. DWR will review 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 4-16-8-1(e).
C. The DWR will review alternative transition
sections and hydraulically equivalent storage
pursuant to Section 4-16-8-1.
d. The DWR will review and approve prior to the
start of construction any Department
projects, dams (as defined in Section 8-16-2)
• and all other state, federal or local units
of government projects, including projects
of the municipality or county.
Section 4-16-8-3: Other Permits. 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 DWR, issued pursuant to Illinois Revised Statutes, Chapter
19, Section 52 et seq. No permit from DWR shall be required if
the Division has delegated this responsibility to the City.
Section 4-16-8-4: Dam Safety Permits. Any work
involving the construction,
modification or removal of a dam as defined in Section 4-16-2
37
per 92 Ill. Adm. Code 702 (Rules for Construction of Dams) shall
obtain an Illinois Division of Water Resources Dam Safety permit
prior to the start of construction of a dam. If the Director of
Building and Zoning finds a dam that does not have a DWR,the
Director of Building and Zoning shall immediately notify the Dam
Safety Section in Springfield and the Illinois Emergency •
Services and Disaster Agency (ESDA).
Section 4-16-8-5: 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
(11) Require the placement of above ground
structures in the floodway, or
(111) In the case of underground stream
1. crossings, the top of the pipe or •
encasement is buried a minimum of 3'
below the existing stream bed, and
(iv) In the case of overhead utilities, no
supporting towers are placed in the
watercourse and such overhead utilities
are designed in such a fashion as not to
catch debris.
b. Storm and sanitary sewer outfalls that:
(1) Do not extend riverward or lakeward of
the existing adjacent natural bank
slope, and
(11) Do not result in an increase in ground
elevation, and 0
(111) Are designed so as not to cause stream
erosion at the outfall location.
38
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.
(11) Materials are not placed higher than
the existing top of bank.
(111) Materials are placed so as not to reduce
the cross -sectional area of the stream
channel or bank of the lake.
e. Temporary stream crossings in which:
(1) The approach roads will be 0.5' (1/2
foot) or less above natural grade.
(11) 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 invent.
(111) 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 rip -rap or gravel.
(iv) All disturbed steam banks will be seeded
or otherwise stabilized as soon as
possible upon installation and again
upon removal of construction.
(v) The access road and temporary crossings
will be removed within one year after
authorization.
Section 4-16-9: Occupation and Use of SFHA
• Area Where Floodways Are Not
Identified. In SFHA or flood plains, where no floodways have
been identified and no base flood or 100-year frequency flood
39
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 100-10
year frequency flood elevation.
Section 4-16-9-1: Development Permit. No
person, firm, corporation, or
governmental body, not exempted by state law, shall commence any
development in a SFHA or flood plan without first obtaining a
development permit from the Director of Building and Zoning.
Application for a development permit shall be made on a form
provided by the Director of Building and Zoning. 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, architect, or surveyor;
the location and dimensions of all buildings and additions too
building; and the elevator at the lowest floor (including
basement) of all proposed buildings subject to the requirements
of Section 4-16-10 of this Ordinance.
The application for a development permit shall also include the
following information:
a. A detailed description of the proposed
activity, its purpose, and intended use;
b. Site location (including legal description)
of the property, drawn to scale, on the
regulatory floodway maps, indicating whether
it is proposed to be in an incorporated or
unincorporated area; 0
C. Anticipated dates of initiation and
completion of activity;
.R
d. 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
lines, names of roads in the vicinity of
• the site, graphic or numerical scale,
and north arrow;
(11) 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), flood plain
• limit, location and orientation of
cross -sections, north arrow, and a
graphical or numerical scale;
(111) 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, ten-year frequency flood
elevation, 100-year frequency flood
elevation, and graphical or numerical
scales (horizontal and vertical); and
• e. Engineering calculations and supporting data
shall be submitted showing that the proposed
41
work will meet the criteria of Section 4-16-
9-4.
f. Any and all other local, state and federal
permits or approvals that may be required for
this type of development.
•
Section 4-16-9-2: Based on the best available
existing data according to the
Illinois State Water Survey's Flood Plain Information Repos-
itory, the Director of Building and Zoning shall compare the
elevation of.the site to the base flood or 100-Year frequency
flood elevation. Should no elevation information exist for the
site, the developer's engineer shall calculate the elevation
according to Section 4-16-5-4. Any development located on land
that can be shown to have been higher than the base flood
elevation as of the site's first Flood Insurance Rate Map
Identification is not in the SFHA and, therefore, not subject to
the requirements of this Ordinance. The Building Official 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.
Section 4-16-9-3: The Director of Building and
Zoning 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 Building and Zoning shall not issue the development
permit unless all required local, state and federal permits have
been obtained.
Section 4-16-9-4: Preventing Increased Damage
No development in the SFHA,
where a floodway has not been determined, shall create a
42
damaging or potentially damaging increase in flood heights or
velocity or threat to public health.
Section 4-16-9-5: 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
1
engineering requirements of Section 4-16-8-
i
1 (a) through (1) for the entire flood plain
as calculated under the provisions of Section
4-16-5-4 of this Ordinance. As an
alternative, the developer should have an
engineering study performed to determine a
floodway and submit that engineering study to
DWR for acceptance as a regulatory floodway.
Upon acceptance of their floodway by the
• Department, the developer shall then
demonstrate that the project meets the
requirements of Section 4-16-7 for the
regulatory floodway. The floodway shall be
defined according to the definition in
Section 4-16-2 of this Ordinance.
b. A development permit shall not be issued
unless the applicant first obtains a permit
from DWR or written documentation that a
permit is not required from DWR.
C. No permit from DWR shall be required if the
Division has delegated permit responsibility
to
the City per
92 Ill. Adm. Code,
Part 708
for
regulatory
floodways, per DWR
Statewide
Permit entitled "Construction in Flood Plains
43
with No Designated Floodways in Northeastern
Illinois".
d. Dam Safety Permits. Any work involving the
construction, modification or removal of a
dam or an on -stream structure to impound
water as defined in Section 4-16-2 shall •
obtain an Illinois Division of Water
Resources Dam Safety permit or letter
indicating a permit is not required prior to
the start of construction of a dam. If the
Director of Building and Zoning finds a dam
that does not have an DWR permit, the
Director of Building and Zoning shall
immediately notify the owner of the dam, the
Illinois ESDA, and the DWR, Dam Safety
Section, in Springfield.
e. The following activities may be permitted
without a Registered Professional Engineer's
review or calculation of a base flood
elevation and regulatory floodway. Such •
activities shall still meet the other
requirements of this Ordinance:
(1) Underground and overhead utilities that:
(a) Do not result in any increase in
existing ground elevations, or
(b) Require the placement of above-
ground structures in the floodway,
or
(c) 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 0
(d) In the case of overhead utilities,
no supporting towers are placed in
' 44
the watercourse and such utilities
are designed in such a fashion as
not to catch debris.
(11) Storm and sanitary sewer outfalls that:
(a) Do not extend riverward or lakeward
• of the existing adjacent natural
bank slope, and
(b) Do not result in an increase in
ground elevation, and
(c) Are designed so as not to cause
stream bank erosion at the outfall
location.
(111) Construction of shoreline and streambed
protection that:
(a) Does not exceed 1000 feet in length
or 2 cubic yards per lineal foot
of streambed.
(b) Materials are not placed higher
than the existing top of bank.
• (c) Materials are placed so as not to
reduce the cross -sectional area of
the stream channel by more than
10%.
(iv) Temporary stream crossings in which:
a) The approach roads will be 0.5'
(1/2 foot) or less above natural
grade.
(b) 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.
• (c) The top of the roadway fill in the
channel will be at least 2' below
the top of the lowest bank. Any
45
fill in the channel shall be non -
erosive material, such as rip -rap
or gravel.
(d) All disturbed stream banks will be
seeded or otherwise stabilized as
soon as possible upon installatiis
and again upon removal of
construction.
(e) The access road and temporary
crossing will be removed within one
year after authorization.
(v) The construction of light poles, sign
posts and similar structures;
(vi) The construction of sidewalks,
driveways, athletic fields (excluding
fences), patios and similar surfaces
which are built at grade;
(vii) The construction of properly anchored,
unwalled, open structures such as
playground equipment, pavilions, and •
carports build at or below existing
grade that would not obstruct the flow
of flood waters;
(viii) 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 tools sheds);
(ix) 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 building, and which do
extend beyond the sides of the existing
46
building that are parallel to the flow
of flood waters;
(x) Minor maintenance dredging of a stream
channel where:
(a) The affected length of stream is
• less than 1000 feet.
(b) The work is confined to
reestablishing flows in natural
stream channels, or
(c) The cross -sectional area of the
dredged channel conforms to that of
the natural channel upstream and
downstream of the site.
f. The flood -carrying capacity within any
altered or relocated watercourse shall be
maintained.
Section 4-16-9-6: Compensatory Storage. When-
ever any portion of a flood
• plain 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. The excavation volume shall be at
least equal to the volume of storage lost due to the fill or
structure. In the case of streams and watercourses, such
excavation shall be made opposite or adjacent to the areas so
filled or occupied. All flood plain -storage lost below the
existing ten-year flood elevation shall be replaced below the
proposed ten-year flood elevation. All flood plain storage lost
above the existing ten-year flood
elevation shall
be replaced
•
above the proposed ten-year flood
elevation. All
such
excavations shall be constructed
to drain freely
and openly to
the watercourse.
47
Section 4-16-10: Permitting Requirements Appli-
cable to All Flood Plain
Areas. In addition to the requirements found in Sections 4-16-
6, 4-16-7 and 4-16-8 for development in flood fringes, •
regulatory floodways, and SFHA or flood plains where no
floodways have been identified (Zones A, AO, AH, AE, Al-A30,
A99, VO, V1-30, VE, V, M or E), the following requirements shall
be met.
Section 4-6-10-1: Public Health Standards
Section 4-6-10-2: 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 FPE.
Section 4-6-10-3: New and replacement water •
supply systems, wells,
sanitary sewer lines and on -site waste disposal systems may be
permitted provided that all manholes or other above ground
opening located below the FPE were watertight.
Section 4-16-10-4: Carrying Capacity and
Notification. For all
projects involving channel modification, fill, or stream
maintenance (including levees), the flood -carrying capacity of
the water course shall be maintained. In addition, the City
shall notify adjacent communities in writing 30 days prior to
the issuance of a permit for the alteration or relocation of the
watercourse. 0
0
OM
Section 4-16-10-5: Protecting Buildings. All
buildings located within a 100-year
flood plain, also known as a SFHA, shall be protected from flood
damage below the flood protection elevation. However, existings
building located within a regulatory floodway shall also meet
• the more restrictive Appropriate Use standards included in
Section 4-16-7. These building protection criteria apply 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% or the building's
market value by more than 50%;
C. Installing a manufactured home on a new site
or a new manufactured home on an existing
site. This building protection requirement
may be met by one of the following methods.
Section 4-16-10-5-1: 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. The 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. 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
49
hydrostatic pressures. The fill shall be
protected against erosion and scour. The
fill shall not adversely affect the flow or
surface drainage from or onto neighboring
properties.
Section 4-16-10-5-2: 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 grade, and consist 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.
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. 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
50
flood protection elevation. Water and sewer
pipes, electrical and telephone lines,
submersible pumps, and other waterproofed
service facilities may be located below the
flood protection elevation.
. d. No area below the flood protection elevation
shall be used for storage of items or
materials.
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.
• Section 4-16-10-5-3: Only a non-residential
building may be structurally
floodproofed (in lieu of elevation) provided that 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. 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. 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) .
51
Section 4-16-10-5-4: Non -conforming structures
located in a regulatory
floodway may remain in use, but may not be enlarged, replaced or
structurally altered. A non -conforming structure damaged by
flood, fire, wind or other natural or man-made disaster may be
restored unless the damage exceeds fifty percent (50%) of its•
market value before it .was damaged, in which case it shall
conform to this Ordinance.
Section 4-16-11: Other Development Requirements
The City Council shall take
into account flood hazards, to the extent that they are known,
in all official actions related to land management, use, and
development.
Section 4-16-11-1: New subdivisions, manufactured
home parks, annexation
agreements, and Planned Unit Developments (PUDs) within the
SFHA shall be reviewed to assure that the proposed
developments are consistent with Sections 4-16-6, 4-16-7,�
16-8, 4-16-9 of this Ordinance and the need to minimize
flood damage. Plats or plans for new subdivisions, mobile
home parks, and PUDs 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 (Ill. Rev. Stat., Ch. 109, Sec.
2) .
Section 4-16-11-2: Proposals for new sub-
divisions, manufactured home
parks, travel trailer parks, planned unit developments PUDs
and additions to manufactured home parks and additions to
subdivisions shall include base flood or 100-year frequency •
flood elevation data and floodway delineations. Where this
information is not available from an existing study filed with
52
the Illinois State Water Survey, the applicant's engineer shall
be responsible for calculating the base flood or 100-year
frequency flood elevation per Section 4-16-5-4 and the floodway
delineation per the definition in Section 4-16-2 and submitting
it to the State Water Survey and DWR for review and approval as
is
best available regulatory data.
•
Section 4-16-11-3: 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.
Section 4-16-11-4: The City Council shall not
approve any PUD or plat of
subdivision located outside the corporate limits unless such
agreement or plat is in accordance with the provisions of this
Ordinance.
Section 4-16-12: Variances. No variances shall
be granted to any
development located in a regulatory floodway as defined in
Section 4-16-2. However, when a development proposal is located
outside of a regulatory floodway, and whenever the standards of
this Ordinance place undue hardship on a specific development
proposal, the applicant may apply'to the Director of Building
and Zoning for a variance. The Director of Building and Zoning
shall review the applicant's request for a variance and shall
submit its recommendation to the City Council.
Section 4-16-12-1: No variance shall be granted
• unless the applicant demon-
strates that:
53
a. The development activity cannot be located
outside the SFHA;
b. An exceptional hardship would result if the
variance were not granted;
C. The relief requested is the minimum
necessary; •
d. There will be no additional threat to public
health, safety, beneficial stream uses and
functions, especially aquatic habitat, or
creation of a nuisance;
e. There will be no additional public expense
for flood protection;
f. The provisions of Section 4-16-6-6 and 4-16-
9-4 of this Ordinance shall still be met;
g. The activity is not in a regulatory floodway;
Section 4-16-12-2: The Director of Building and
Zoning shall notify an
applicant in writing that a variance from the requirements of
Section 4-16-10 that would lessen the degree of protection to
building will:
a. Result in increased premium rates for
flood insurance up to amounts as high as $25
for $100 of insurance coverage;
b. Increase the risk to life and property; and
C. Require that the applicant proceed with
knowledge of these risks and that he will
acknowledge in writing that he assumes the
risk and liability.
Section 4-16-12-3: Variances requested in
connection with restoration of
a site or building listed on the National Register of Histori*
Places or documented as worthy of preservation by the Illinois
Historic Preservation Agency may be granted using criteria more
54
Historic Preservation Agency may be granted using criteria more
permissive than the requirements of Section 4-6-11-1 and
4-6-11-2.
Section 4-16-13: Disclaimer of Liability. The
degree of flood protection
0 required by this Ordinance is considered reasonable for
regulatory purposes and is based on available information
derived from engineering and scientific methods of study.
Larger floods may occur or flood heights may be increased by
man-made or natural causes. This Ordinance does not imply that
development,.either inside or outside of the SFHA, will be free
from flooding or damage. This Ordinance does not create
liability on the part of the City or any officer or employee
thereof for any flood damage that results form reliance on this
Ordinance or any administrative decision made lawfully,
thereunder.
Section 4-16-14: 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 Building and Zoning may determine that a violation
of the minimum standards of this Ordinance exists. The Director
of Building and Zoning shall notify the owner in writing of such
violation.
Section 4-16-14-1: If such owner fails after ten
days' notice to correct the
violation:
a. The City 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 the Ordinance.
55
b. 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.
C. . A separate offense shall be deemed committee
upon each day during or on which a violation
occurs or continues.
d. The City may record a notice of violation on
the title to the property.
Section 4-16-14-2: The Director of Building and
Zoning 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.
Section 4-16-14-3: Nothing herein shall prevent
the City from taking such
other lawful action to prevent or remedy any violations. All •
costs connected therewith shall accrue to the person or persons
responsible.
Section 4-16-15: Abrogation and Greater
Restrictions. This Ordinance
is not intended to repeal, abrogate or impair any existing
easements, covenants, or deed restrictions. Where this
Ordinance and other ordinances, easements, covenants, or deed
restrictions conflict or overlap, whichever imposes the more
stringent restrictions shall prevail. This Ordinance is
intended to repeal the original ordinance or resolution which
was adopted to meet the National Flood Insurance Proqram
regulations, but is not intended to repeal the resolution whic
the City passed in order to establish initial eligibility for
the program.
56
•
•
Section 4-16-16: 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 4-16-17: Effective Date. This
Ordinance shall be in full force and effect from and after its
passage and approval and publication, as required by law.
Section 2: All ordinances or parts of
ordinances in conflict herewith are
hereby repealed.
Section 3: This ordinance shall be in full
force and effect from and after its
passage, approval and publication in the manner provided by law.
Introduced: , 1990
Adopted: � ��► 1990
Appro e G/G%� �2 GLI �7` 1990
Mayor
ATTEST:
City Clerk
ved asaCounse
orpora
57
d