O-92-38SMB07774A3081192
ORDINANCE NO. 0 -92 -38
AN ORDINANCE PROVIDING FOR THE ADOPTION OF
THE VILLAGE OF DEERFIELD STORMWATER MANAGEMENT CODE
Published in pamphlet form this
17th day of August , 1992
by the President and Board of Trustees
of Deerfield.
ORDINANCE NO. 0 -92 -38
AN ORDINANCE PROVIDING FOR THE ADOPTION OF
THE VILLAGE OF DEERFIELD STORMWATER MANAGEMENT CODE
WHEREAS, the Lake County Stormwater Management Commission
adopted the Lake County Comprehensive Stormwater Management Plan
on June 11, 1990; and
WHEREAS, the Lake County Stormwater Management Commission
has determined that uniform and consistent enforcement of
stormwater management will be enhanced by municipalities adopting
the standards of the Lake County Comprehensive Stormwater
Management Plan; and
WHEREAS, the President and Board of Trustees of the Village
of Deerfield have determined that the best interests of the
Village will be served by the adoption of a stormwater management
code encompassing the Lake County stormwater management
standards.
NOW, THEREFORE, BE IT ORDAINED BY THE PRESIDENT AND BOARD OF
TRUSTEES OF THE VILLAGE OF DEERFIELD, LAKE AND COOK COUNTIES,
ILLINOIS AS FOLLOWS:
SECTION That there is hereby adopted by the President and
ONE: Board of Trustees for the purpose of establishing
stormwater management standards, that certain Code
attached hereto and made a part hereof to be known as the
"Village of Deerfield Stormwater Management Code," of which not
less than three copies have been and are now filed in the Office
of the Village Manager and the same are hereby adopted and
incorporated as fully as if set out in length herein, and from
the date on which this ordinance shall take effect, the
provisions hereof shall be controlling within the corporate
limits of the Village of Deerfield.
SECTION That the Village of Deerfield Stormwater
TWO: Management Code shall be enforced by the Village
Manager.
SECTION That nothing in the V
THREE: Stormwater Management
shall be construed to
proceeding now pending in any court,
liability incurred, nor any cause or
existing, under any act or ordinance
any right or remedy of any character
affected by this ordinance.
illage of Deerfield
Code, as hereby adopted
affect any suit or
or any rights acquired, or
causes of actions accrued or
repealed hereby, nor shall
be lost, impaired or
ORDINANCE NO. 0 -92 -38
AN ORDINANCE PROVIDING FOR THE ADOPTION OF
THE VILLAGE OF DEERFIELD STORMWATER MANAGEMENT CODE
SECTION That the invalidity of any section or provision of
FOUR: the Village of Deerfield Stormwater Management
Code, as hereby adopted shall not invalidate other
sections or provisions thereof.
SECTION That Chapter 20 of the Municipal Code of the
FIVE: Village of Deerfield, as amended, be and the same
is hereby further amended by adding at the end
thereof the following:
That there is hereby adopted by the President and
Board of Trustees for the purpose of establishing
stormwater management standards, that certain Code
attached hereto and made a part hereof to be known
as the "Village of Deerfield Stormwater Management
Code," of which not less than three copies have
been and are now filed in the Office of the
Village Manager and the same are hereby adopted
and incorporated as fully as if set out in length
herein, and from the date on which this ordinance
shall take effect, the provisions hereof shall be
controlling within the corporate limits of the
Village of Deerfield.
SECTION That the Village Clerk is hereby directed to
SIX: publish this Ordinance in pamphlet form.'
SECTION That this Ordinance shall be in full force and
SEVEN: effect from and after its passage, approval and
publication, as provided by law.
AYES: Ehlers, Rosenthal, -Seidman, Swartz (4)
NAYS: None (0)
ABSENT: Marovitz, Swanson (2)
PASSED this 17th day of August A.D., 1992.
APPROVED this 17th day of August , A.D., 1992
VfrLAGE PRESIDENT
ATTEST:
VrMAGE CLERK
Village of Deerfield Stormwater Management Code
AUGUST 1992
INTRODUCTION
The Village of Deerfield Stormwater Management Code (the "Code ")
sets forth the minimum requirements for stormwater management for
new developments in the Village of Deerfield, Illinois. The
standards for stormwater management set forth in this Code
reflect the standards set forth in the Lake County Comprehensive
Stormwater Management Plan, adopted by ordinance in Lake County
on June 11, 1990. By incorporating these standards, the Code is
part of a unified county -wide structure of stormwater management
which provides for a uniform system of enforcement of stormwater
management standards. This Code is intended to supersede and
replace any stormwater management guidelines contained in the
Village of Deerfield Municipal Code which conflict with the
provisions of this Code.
Article I: AUTHORITY AND PURPOSE
A. AUTHORITY
This Code is enacted pursuant to the home rule powers
granted to the Village by Section 6 of Article VII of
the Illinois Constitution of 1970.
B. PURPOSE
The purpose of this Code is to establish reasonable
rules and regulations for development in order to:
1. Prevent additional harm due to periodic flooding
including loss of life and property and threats
and inconveniences to public health, safety and
welfare; and
2. Assure that new development does not increase
flood and drainage hazards to others, or create
unstable conditions susceptible to erosion; and
3. Create no new financial burden on the taxpayer for
flood control projects, repairs to flood damaged
public facilities and utilities, and for flood
rescue and relief operations; and
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Village of Deerfield
4. Protect, conserve and promote the orderly
development of land and water resources; and
5. Protect buildings and improvements to buildings
from flood damage to the greatest extent possible;
and
6. Conserve the natural hydrologic, hydraulic, water
quality and other beneficial functions of
watercourses, floodplains and wetlands; and
7. Prevent additional disruption of the economy and
governmental services due to stormwater and flood
drainage; and
8. Maintain eligibility for the Village of Deerfield
in the National Flood Insurance Program by
equalling or exceeding its requirements and thus
make federally subsidized flood insurance
available at reduced rates.
Article II: CODE ENFORCEMENT
A. The Village Manager shall be the Enforcement Officer of
the Code. One of the primary duties of the Enforcement
Officer shall be to review all watershed development
applications to assure development sites will be
reasonably free from flooding.
B. Adopted Basin Plans will be the basis for more specific
regulations, if necessary and appropriate. These
additional or more specific regulations will apply only
in the specific study area of the Basin Plan and
supersede those of this Code only upon amendment to the
Watershed Development Code.
C. The Enforcement Officer may require deed restrictions,
performance bonds or sureties, as -built certification
or maintenance guarantees to assure projects are built
according to permitted plans.
Article IV: WATERSHED DEVELOPMENT PERMITS
A. GENERAL
1. Regulated Development
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Village of Deerfield
No person, firm, corporation or governmental
agency, unless specifically exempted, shall
commence any development regulated by this Code on
any lot or parcel of land without first obtaining
a Watershed Development Permit from the Village
Manager. A permit shall be issued if the proposed
development meets the requirements of this Code or
its certified community equivalent. A Watershed
Development Permit is required for any
development, including finalization of a plat,
replat, lot - split, Planned Unit Development (PUD)
or Manufactured Home Park site plan, which:
a. Is located in a Regulatory Floodplain,
including all 100 -year frequency floodplains
draining greater than 100 acres and all
depressional storage areas with a surface
area greater than 1/4 acre at the 100 -year
frequency event, or
b. Disturbs a cumulative total of one (1) or
more acres of wetlands, or
C. Modifies a watercourse where the tributary
drainage area is twenty (20) or more acres,
or
d. The land area of an undeveloped ownership
parcel, or the undeveloped land area of an
ownership parcel developed prior to the
effective date of this Code and consists of:
(1) Single family detached residential
developments with five (5) or more
units; or
(2) Multi- family, non - residential, and other
developments of three (3) acres or more
in size, or which will result in an
impervious surface area of 50% or more
of the development site; or
(3) Any public
resulting i
(1.5) acres
surface per
more than o
impervious
project.
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road construction project
n more than one and one half
of additional impervious
mile on linear projects, or
ne (1) acre of additional
surface per nonlinear
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Village of Deerfield
2. Exempted Development
No Watershed Development Permit is required for
any development for which there exists, prior to
the effective date of the Code:
a. An approved building permit, or
b. An (1) approved preliminary plat or (2)
annexation agreement or (3) in the case of
industrial or commercial subdivision
replatting, no increase in the approved floor
area ratio or impervious surface area for
developments without a previously approved
floor area ratio, from the Village of
Deerfield; that includes an engineering study
with a drainage component consistent with
Article IV Section B.2.b(5); however in this
case the proposed development is not exempt
from meeting the Floodplain Development
Standards of Article IV, Section C, or
C. In the case of a public road development
project,
(1) An awarded construction contract, or
(2) An approved preliminary engineering plan
consistent with the applicable
ordinances or regulations of an
appropriate jurisdictional authority.
However in this case the proposed development
is not exempt from meeting the Floodway
Standards in Article IV, Sections C.3 and C.4
of this Code.
3. Development Classification
All activities requiring a Watershed Development
Permit shall be classified as a minor, major, or
public road development. The definition for each
classification follows:
a. Minor Development
A minor development is defined as any
development that:
(1) is not located in depressional storage
area larger than 0.5 acre -feet or is not
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Village of Deerfield
located in any other portion of a
Regulatory Floodplain, or
(2) does not disturb a cumulative total of
one (1) or more acres of wetlands, or
(3) modifies a watercourse less than 100
acres, or
(4) consists of:
(a) Single family detached residential
development of less than ten (10)
acres; or
(b) Single family detached residential
development of ten (10) acres or
more with a gross density of less
than .5 unit per acre, and an
impervious cover area of less than
fifteen (15) percent; or
(c) Multi- family, non - residential and
other developments of less than
three (3) acres requiring a
Watershed Development Permit.
b. Public Road Development
A public road development is defined as any
development activity which takes place in a
highway right -of -way or part thereof that is
administered and funded by a public agency
under its respective highway jurisdiction.
Rehabilitative maintenance and in -kind
replacement are not considered to be a public
road development and do not require a permit,
unless located in a regulatory floodway.
C. Major Development
A major development is defined as all other
development.
4. Approvals Prior to Permitting
Prior to the issuance of a watershed development
permit, the applicant may request a Conditional
Approval or an Earth Change Approval.
a. Conditional Approval
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Village of Deerfield
Conditional approval of the regulatory
floodplain and floodway delineation, flood
conveyance path, wetland delineation, runoff
volume reduction hierarchy, and the
detention and bypass computations for a
development may be granted by the Enforcement
Officer. The conditional approval will be
based on conformance with the performance
standards, and the submittal of the
appropriate application requirements as
listed in Article IV, Section B, C, D and E.
A letter will be sent to the applicant
stating the results of the review and the
conditions placed on any approvals.
b. Earth Change Approval
If all the performance standards and
application requirements in Article IV,
Section B, C, D and E have been met, except
for obtaining all the required local, state
and federal approvals, a request for the
commencement of grading activities may be
made on a site prior to the issuance of a
Watershed Development Permit. The proposed
grading activity may commence with written
approval from the Enforcement Officer at the
Enforcement Officer's discretion. The
written approval will state the conditions
and limitations of the proposed grading
activities. No development activity may
occur in those portions of the site for which
state and federal permits are required,
except for IEPA sewer and water extension
permits.
5. Permit Fees and Application Review Times
A fee schedule shall be developed and implemented
by Village of Deerfield. Permit applications
shall be reviewed within 30 days of receipt so as
to determine whether they are complete. Once this
determination has been made, the permit
applications will be reviewed within 60 days,
unless the Enforcement Officer informs the
applicant of the need and cause for an extension.
Two 30 day extensions may be used by the
Enforcement Officer to complete the application
review. If the Enforcement Officer has not denied
the permit application for cause after these time
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Village of Deerfield
periods have elapsed, the application shall be
deemed approved.
6. Contiguous Property
In order to preclude inappropriate phasing of
developments to circumvent the intent of this
Code, when a proposed development activity will
occur on a lot or parcel of land that has
contiguous lots or parcels of lands owned by the
same property owner, then the criteria as defined
in this section will be applied to the total land
area compiled from aggregate ownership parcels.
If this aggregate ownership land area is greater
than the minimum area requirements defined in
Article IV Section A.1, then a Watershed
Development Permit will be required.
7. Permit Extensions and Terminations
Among the causes for terminating a permit during
its term or for denying a permit extension
include, but are not limited to the following:
a. Noncompliance with any condition of the
permit, or
b. The permittee's failure to disclose fully all
relevant facts in the application process or
the permittee's misrepresentation of any
relevant facts at any time, or
C. If the authorized work is not commenced
within three years after issuance of the
permit or, if the authorized work is
suspended or abandoned, for a period of
twelve months after the time of commencing
the work, unless an extension has been
granted in writing by the Enforcement
Officer. The extension should be requested
of the Enforcement Officer in writing no
sooner than 90 days prior to the termination
of the permit.
B. ALL DEVELOPMENT
The following performance standards, application
requirements and other provisions apply to all
development requiring a permit. Subsequent sections
include additional provisions for development in a
floodplain, wetlands and public roads.
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Village of Deerfield
1. Performance Standards
a. Plats and Site Plans
(1) The performance standards for all
development (Article IV) shall be
considered in site planning and
appropriately addressed in the drainage
plan component of plats, replats,
manufactured home parks and Planned Unit
Developments.
(2) In addressing Article IV, Section B.l.d
"Runoff Volume Reduction Hierarchy"
streets, blocks, lots, easements, parks
and other public grounds shall be
located and lined out in such a manner
as to preserve and utilize natural
streams and channels whenever possible.
(3) Plats, replats, manufactured home parks
and PUDs shall show the Base Flood
Elevation (BFE) and floodway limits.
The plats, replats, manufactured home
parks, PUDS's, or engineering plans and
studies shall include a signed statement
by a Registered Professional Engineer
that accounts for changes in the
drainage of surface waters in accordance
with the Plat Act.
(4) All plats and subdivisions which border
on or include public bodies of water as
defined by IDOT /DWR shall be submitted
to IDOT /DWR for review and approval.
(5) Stormwater facilities shall be
functional before building permits are
issued for residential and non-
residential subdivisions.
(6) Stormwater facilities shall be
functional where practicable for single
parcel developments before general
construction begins.
b. Runoff Calculations
(1) For areas 100 acres or greater, and for
the determination of detention storage
requirements, an SMC approved
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Village of Deerfield
hydrograph - producing runoff calculation
method shall be used.
(2) The Rational Method may be used to
calculate discharges for areas of less
than 100 acres. The Rational Method
shall not be used to determine detention
storage requirements.
(3) "Frequency Distributions and
Hydroclimatic Characteristics of Heavy
Rainstorms in Illinois ", Bulletin 70,
1989 (Table 13), prepared by the
Illinois State Water Survey shall be
used in determining design rainfall.
(4) Runoff calculations for all tributary
land shall be based on anticipated
future land use conditions or existing
land use conditions, whichever yields
the greater runoff. Anticipated future
land use conditions will be based on
future land use and existing storage
facilities. Future detention facilities
may be used for anticipated future land
use conditions if approved by the SMC
Chief Engineer or for tributary drainage
areas less than 100 acres the
Enforcement Officer. Existing land use
conditions will be based on existing
land use and existing storage
facilities. For each storm event,
runoff calculations will be based on the
critical duration.
(5) Existing depressional storage volume
will be maintained and the volume of
detention storage provided to meet the
requirements of this Code shall be in
addition to the existing storage.
(6) Where in SMC's opinion, fee -in -lieu of
on -site detention is an option, the SMC
will fund the cost to upgrade existing
or future conveyance systems if the
upgrade is consistent with an approved
SMC Basin Plan.
C. Release Rates and Discharges
(1) Unless otherwise specified in an SMC -
adopted Basin Plan, release rates shall
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Village of Deerfield
not exceed 0.04 cubic feet per second
per acre for the 2 -year, 24 -hour storm
event nor 0.15 cubic feet per second per
acre for the 100 -year, 24 -hour storm
event. The release rate requirement
shall apply to the entire ownership
parcel unless otherwise approved by the
Enforcement Officer. The release rate
requirements shall only apply to
developments listed in Article IV,
Section A.1.d.
(2) All concentrated stormwater discharges
leaving a site must be conveyed into a
well- defined receiving channel with
adequate downstream stormwater capacity.
(3) All areas of the development must be
provided an overland flow path that will
pass the 100 -year flow without damage to
structures or property.
(4) The design of stormwater drainage
systems shall not result in the
interbasin transfer of drainage, unless
no reasonable alternative exists and
there is no legal restraint preventing
such transfer.
d. Runoff Volume Reduction Hierarchy
(1) An applicant shall choose a strategy to
meet the release rate requirements that
minimizes the increase in runoff volumes
and rates from the development. The
applicant shall use the following
hierarchy in preparing a drainage plan:
1) Preservation of floodplains and
wetland areas; 2) Minimization of
impervious surfaces to be created on the
property; 3) Flow attenuation by use of
open vegetated swales and retention of
existing natural streams and channels;
4) Infiltration of runoff onsite; 5)
Stormwater retention structures; 6) Wet
detention structures; 7) Dry detention
structures; 8) Storm sewers.
e. Detention Facilities
(1) All stormwater infiltration, retention
and detention facilities shall be
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Village of Deerfield
provided with an emergency overflow
structure capable of passing the 100 -
year inflow rate without damages to
structures or property.
(2) Single pipe outlets shall have a minimum
inside diameter of 12 inches. If design
release rates call for smaller outlets,
structures such as perforated risers, or
flow control orifices shall be used.
(3) Stormwater infiltration, retention and
detention facilities required to meet a
development's discharge requirements
shall be designed to by -pass offsite
tributary flow from streams and channels
unless approved by the Enforcement
Officer.
(4) Any work involving the construction,
modification or removal of a dam as
defined in Article II per 92 III. Adm.
Code 702 (Rules for Construction of
Dams) shall obtain an Illinois Division
of Water Resources Dam Safety permit
prior to the start of such activity.
(5) Stormwater retention and detention
facilities shall not be constructed in a
regulatory floodplain unless approved by
the Enforcement Officer. If a retention
or detention facility is constructed in
a regulatory floodplain, lost floodplain
storage volume due to fill structures
and detention storage will be replaced
with compensatory storage.
f. Fee -in -Lieu of On -Site Detention
(1) The SMC may require, or the applicant
may request, the payment of a fee -in-
lieu of on -site detention to fulfill all
or part of the on -site detention
requirement for a development.
(2) The SMC may reject any request to use a
fee -in -lieu of on -site detention by the
applicant which the SMC determines does
not benefit the drainage system.
(3) Fee -in -lieu of on -site detention shall
be the lesser of: 1) the fee computed
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Village of Deerfield
for each acre foot of storage exempted
in accordance with the procedures and
schedules as approved by the SMC or 2)
the estimated cost, as verified by SMC
of the applicant's proposed and approved
on -site detention, including land costs
had the Village of Deerfield allowed its
construction.
(4) A fund will be maintained for each
watershed for the purpose of identifying
and controlling all revenues and
expenses derived from stormwater
drainage services resulting from fee -in-
lieu of on -site detention exemptions.
All fees -in -lieu of on -site detention
received from each watershed shall be
deposited in these funds. Disbursements
for costs to mitigate stormwater impacts
of developments shall be made from the
appropriate watershed fund.
(5) Criteria
The following requirements must be met
before a fee -in -lieu of on -site
detention will be utilized:
(a) The downstream drainage system has
adequate stormwater capacity; and
(b) The elimination of on -site
detention facilities will not
result in negative impacts to the
drainage system.
g. Conveyance System
(1) Storm Sewer and Swales
(a) The 10 -year design storm shall be
used as a minimum for the design of
storm sewers and appurtenances.
(b) Connections to sanitary sewers or
existing agricultural drainage
systems (tiles) will not be
permitted for new developments.
However, with the approval of the
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Village of Deerfield
Enforcement Officer in certified
communities, connections to
existing agricultural drainage
systems may be allowed if the
applicant demonstrates that the
existing system has adequate
hydraulic capacity and structural
integrity. Field tile systems
disturbed during the process of
land development must be
reconnected by those responsible
for their disturbance unless the
approved drainage plan includes
provisions for these.
(c) All storm sewers shall be located
in a public road right -of -way or
maintenance easement of sufficient
size to maintain or re- construct
the sewer.
(d) All on -site stormwater conveyance
systems shall be designed and
constructed to withstand the
expected velocity of flow from all
events up to the 100 -year frequency
storm without erosion.
Stabilization adequate to prevent
erosion shall be provided at the
inlets and outlets for all pipes
transitions and paved channels.
(e) Within the parcel being developed,
an overflow easement shall be
provided which conveys the portion
of the 100 -year runoff not carried
in a storm sewer without damage to
structures or property.
(2) Streams and Channels
(a) Natural streams and channels are to
be conserved.
(b) If channel modification occurs, the
physical characteristics of the
modified channel shall meet the
existing channel in length, cross -
section, slope, sinuosity and
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carrying capacity of the original
channel. Hydraulically equivalent
compensatory storage is required
for fill or structures and shall be
at least equal to the volume of
floodplain storage lost.
(c) Removal of streamside (riparian)
vegetation shall be limited to one
side of the channel.
(d) Clearing of channel vegetation
shall be limited to that which is
essential for construction of the
channel.
(e) When the four previous provisions
can not be met, a stream or channel
mitigation plan shall be submitted
for review and approval to the
Enforcement Officer. The plan
shall show how the lost functions
are replaced.
(f) All disturbed areas associated with
a channel modification shall be
seeded or otherwise stabilized
immediately upon completion of site
grading construction.
(g) If channels are modified an
effective means to reduce
sedimentation and degradation of
downstream water quality must be
installed before excavation begins
and must be maintained throughout
the construction period.
(h) New or relocated channels shall be
built in the dry and all items of
construction, including vegetation,
shall be completed prior to
diversion of water into the new
channel.
(i) Streams and channels shall be
expected to withstand all events up
to the 100 -year frequency without
increased erosion. The use of
armoring of banks using bulkheads,
rip -rap and other materials shall
be avoided. Armoring shall only be
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Village of Deerfield
used where erosion cannot be
prevented in any other way such as
use of vegetation or gradual
slopes. Such armoring shall have
minimal impact on other properties,
watercourses, and the existing land
configuration.
(j) A minimum maintenance easement of
12 feet from top of bank is
required along one side of all
channels draining 20 or more acres.
All drainage easements shall be
accessible to vehicular equipment;
however, linear accessibility for
vehicular equipment is not
required.
(k) Construction vehicles shall cross
streams by the means of existing
bridges or culverts. Where an
existing crossing is not available,
a temporary crossing shall be
constructed in which:
(i) The approach roads will be 0.5
feet or less above natural
grade.
(ii) 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.
The top of the roadway
fill in the channel will
be at least 2 feet 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 stream 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
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Village of Deerfield
within one year after
installation, unless an
extension of time is granted
by the Enforcement Officer.
h. Lakes, Ponds and Wetlands
(1) All direct discharges of stormwater into
wetlands or existing lakes and ponds due
to new development shall be required to
divert and detain the initial one -half
inch of runoff immediately before
discharge into lakes, ponds, and
wetlands.
i. Buffer Areas
(1) Buffer areas are divided into two types,
linear buffers and water body buffers.
(a) Linear buffers shall be designated
along all channels.
(i) When the distance across the
channel between the ordinary
high water marks is greater
than 20 feet, the minimum
buffer width shall be 30 feet
on each side of the channel.
(ii) When the distance across the
channel between the ordinary
high water marks is less than
20 feet, the minimum buffer
width shall be 20 feet on each
side of the channel.
(b) water body buffers encompass all
non - linear bodies of water and
include exceptional functional
value wetlands, other wetlands with
existing, adjacent native
vegetation that performs a buffer
function, lakes and ponds.
(i) For all water bodies with a
surface area greater than one
(1) acre, a minimum buffer
width of 30 feet extending
from the delineated water
body boundary shall be
established.
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Village of Deerfield
(ii) For all water bodies with a
surface area less than or
equal to one (1) acre, a
minimum buffer width shall be
established such that the area
of the buffer is one -half
(1/2) the area of the water
body, to a minimum width of 10
feet.
(2) No buffers shall be required for
wetlands, other than for exceptional
functional value wetlands or wetlands
that have existing native vegetative
buffers, if there will exist adjacent to
the wetland a minimum setback of 30
feet. In situations where a 30 foot
setback is not feasible, then best
management practices shall be
implemented to offset the encroachment
impacts.
(3) Buffer areas shall be made up of native
midwest vegetation. The use of native
Lake County riparian vegetation is
preferred in the buffer strip.
(4) The boundary of the buffer area for
lakes, ponds and channels shall be
determined by reference to the
watercourses ordinary high water mark.
For wetlands the boundary of the buffer
area shall be determined by the wetland
delineation report. A property may
contain a buffer area that originates
from a watercourse on another property.
(5) Constructed stormwater management
features which require a buffer may not
be located such that the required
boundaries of buffer areas extend into
adjoining property or the ultimate
boundaries of public right -of -way as
determined by the local road authority.
(6) If an existing buffer area is disturbed
during construction, the vegetated
buffer strip shall be,re- established
upon completion of construction.
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(7) Access through buffer areas shall be
provided, when necessary, for
maintenance purposes.
(8) Roadside drainage ditches, channels
draining twenty acres or less,
conveyance systems between on -site
detention facilities, detention
facilities, and transverse crossings of
public road construction projects are
exempt from buffer requirements.
(9) Where practical, stormwater shall
discharge into a buffer area rather than
directly into a watercourse. Such
discharges shall enter the buffer as
unconcentrated flow with appropriate
energy dissipation measures to prevent
excessive erosion and scour.
(10) All buffer areas shall be maintained
free from development including
disturbance of the soil, dumping or
filling, erection of structures and
placement of impervious surfaces except
as follows:
(a) A buffer area may be used for
passive recreation (e.g.,
birdwatching, walking, jogging,
bicycling, horseback riding and
picnicking) and it may contain
pedestrian, bicycle or equestrian
trails, provided that the created
path is no wider than ten (10)
feet. If the path leads to a
wetland, it must be a winding path.
(b) Structures and impervious surfaces
may occupy a maximum of 20 percent
of the required buffer or setback
area provided the runoff from such
facilities is diverted away from
the watercourse or such runoff is
directed to enter the buffer area
as unconcentrated flow.
(c) Utility maintenance and maintenance
of drainage facilities and drainage
easements shall be allowed.
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(d) Anchoring and placement of boat
docks and piers.
j. Soil Erosion and Sediment Control
(1) Soil erosion and sediment control
related measures are required for any
land disturbance activity permitted
under Article IV, Section A. The
following requirements shall be met:
(a) Soil disturbance shall be conducted
in such a manner as to minimize
erosion. Soils stabilization
measures shall consider the time of
year, site conditions and the use
of temporary or permanent measures.
(b) Properties and watercourses located
downstream from development sites
shall be protected from erosion and
sedimentation. At points where
concentrated flow leaves a site,
stable downstream facilities are
required.
(c) Soil erosion and sediment control
features shall be constructed prior
to the commencement of upland
disturbance.
(d) Permanent or temporary soil
stabilization shall be applied to
disturbed areas within 15 calendar
days of the end of final grading of
the soil. Permanent soil
stabilization measures shall be
applied to channels (including bed
and banks) within 15 calendar days
of the end of primary disturbance
of the channel. Permanent or
temporary vegetation shall not be
considered established until
sufficient ground cover is mature
enough to control erosion.
(e) Disturbed areas draining less than
1 acre shall be protected by a
filter barrier (including filter
fences, straw bales, or equivalent
control measures) to control all
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off -site runoff. Vegetated filter
strips, with a minimum width of 25
feet, may be used as an alternative
only where runoff in sheet flow is
expected.
Disturbed areas draining more than
1 but fewer than 5 acres shall be
protected by a sediment trap or
equivalent control measure at a
point downslope of the disturbed
area.
Disturbed areas draining more than
5 acres, shall be protected by a
sediment basin or equivalent
control measure at a point
downslope of the disturbed area.
(f) All storm sewer facilities that are
or will be functioning during
construction shall be protected,
filtered, or otherwise treated to
remove sediment.
(g) If dewatering services are used
adjacent properties shall be
protected. Discharges shall enter
an effective sediment and erosion
control measure.
(h) All temporary erosion and sediment
control measures shall be removed
within 30 days after final site
stabilization is achieved or after
the temporary measures are no
longer needed. Trapped sediment
and other disturbed soil areas
should be permanently stabilized.
(i) A stabilized mat of aggregate
underlain with filter cloth shall
be located at any point where
traffic will be entering or leaving
a construction site to or from a
public right -of -way, street, alley
or parking area.
(j) Earthen embankments shall be
constructed with side slopes no
steeper than 3H:1V.
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(2) Maintenance
All temporary measures and permanent
erosion and sediment control must be
continuously maintained in an effective
working condition.
2. Application Requirements
All the following application requirements will be
required unless waived by the Enforcement Officer.
a. Application Requirements for Minor
Developments
Developments
(1) Name and legal address of the applicant.
Common address and legal description of
the site and the parcel identification
number where the development will take
place.
(2) A general description of the existing
and proposed drainage system including
all discharge points, collection,
conveyance, and storage facilities.
(3) A grading plan showing proposed and
existing contours.
(4) A site drainage plan locating drainage
features, overland flow paths,
stormwater management facilities,
floodplains and wetlands boundaries.
(5) An area drainage plan locating the
proposed development in the watershed.
(6) A description and depiction of measures
to be taken to control erosion.
b. Application Requirements for Major
(1) Name and legal address of the applicant,
and common address of the location where
the development will take place, mailing
address of the property owner and the
applicant or applicant's agent's
signature.
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(2) A topographic map of the existing
conditions of the development site
showing the location of all roads, all
drainageways, the boundaries of
predominate soil types, the boundaries
of predominate vegetation, and the
location of any drainage easements,
detention or retention basins, including
their inflow and outflow structures, if
any. The map shall also include the
location, size and flowline elevations
of all existing storm or combined sewers
and other utility lines within the site.
The map shall be prepared using a
minimum 2 -foot contour interval and
shall be prepared at an appropriate
scale for the type of project and shall
include specifications and dimensions of
any proposed channel modifications,
location and orientation of cross -
sections, if any, north arrow, and a
graphic or numerical scale. All
elevations shall be referenced to NGVD.
(3) Include cross - section views for the
drainage system showing existing and
proposed conditions including principal
dimensions of the work, and existing and
proposed elevations, normal water and
calculated high water elevations, and
overland flow depth and path.
(4) A vicinity map shall be included along
with the parcel identification numbers
of all parcels comprising the proposed
development.
(5) A report describing the hydrologic and
hydraulic analyses performed for the
project. The report shall include the
name of stream or body of water
affected, a statement of purpose of
proposed activity, anticipated dates of
initiation and completion of activity,
and a detailed determination of the
runoff for the project site under
existing and developed conditions. This
includes documentation of the design
volumes and rates of the proposed runoff
for each portion of the watershed
tributary to the drainage system and the
effects the improvements will have upon
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the receiving channel and high water
elevations. Runoff calculations shall
include all discharges entering the site
from upstream areas.
(6) A section in the hydrologic and
hydraulic analysis report describing how
the Runoff Volume Reduction Hierarchy
(as described in Article IV, Section
B.l.d.) was used in evaluating the
stormwater management needs of the site.
(7) For detention facilities, a section in
the hydrologic and hydraulic analysis
report that includes a plot or
tabulation of storage volumes and water
surface areas with corresponding water
surface elevations, stage- discharge or
outlet rating curves, and design
hydrographs of inflow and outflow for
the 2 -year, 24 -hour and the 100 -year,
24 -hour storm events under existing and
developed conditions.
(8) A soil erosion and sedimentation control
plan for all disturbed areas, which
includes:
(a) A site map prepared at the same
scale as the drainage plan that
identifies both temporary and
permanent vegetative and structural
erosion and sediment control
measures to be implemented.
(b) A narrative description of the
sequencing of grading and soil
disturbance and construction
activities, the temporary and
permanent sediment and erosion
control measures to be implemented
to mitigate any negative effects of
grading including: supporting
calculations; estimated schedule
for installing, maintaining and
removing both temporary and
permanent structures; and the final
stabilization and revegetation
measures.
(9) A maintenance plan for the ongoing
maintenance of all drainage system
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components including wetlands is
required prior to plan approval. The
plan shall include:
(a) Maintenance tasks.
(b) The party responsible for
performing the maintenance tasks.
(c) A description of all permanent
public or private access
maintenance easements.
(d) A description of dedicated sources
of funding for the required
maintenance.
(10) When a proposed development has the
potential for affecting a drainage
system component maintained by an active
Drainage District, a copy of the
detailed drainage plan shall be
forwarded to the Drainage District for
concurrent review.
(11) The Application shall meet the
requirements of this Code and shall be
certified and sealed by a registered
professional engineer.
C. FLOODPLAIN DEVELOPMENTS
1. Base Flood Elevation & Location of Floodplain and
Floodway
a. The Base Flood Elevations (BFE) shall be as
delineated on the 100 year profile and
floodplain maps as noted below;
(1) SMC regulatory floodplain maps and
profiles, approved by the SMC for
regulatory use after a 60 day public
review and comment period and accepted
by IDOT /DWR and FEMA for SMC regulatory
use, as listed in Appendix B, or
(2) Should no SMC approved regulatory
floodplain map and profile exist for the
site, the FEMA Flood Insurance Study
maps and profiles, as listed in Appendix
C, or
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(3) The best available information as
determined by the SMC.
(4) In the case of FEMA delineated "AH
Zones" the elevation noted on the map
shall be the BFE. In the case of FEMA
delineated "AO Zones" the BFE shall be
the depth number shown on the map added
to the highest adjacent grade, or at
least two feet above the highest
adjacent grade if no depth number is
provided.
b. The location of the regulatory floodway and
its accompanying flood elevation shall be as
delineated on the IDOT /DWR designated
regulatory floodway maps listed in Appendix
D.
C. When no base flood or 100 -year frequency
flood elevation information exists, the base
flood or 100 -year frequency flood elevation
shall be determined by the registered
professional engineer using an appropriate
model or technique as approved by the SMC or
IDOT /DWR or their designee. In the case of
riverine floodplains, the flood elevation
determination shall be submitted to SMC for
approval prior to issuance of a watershed
development permit.
(1) Along any watercourses draining more
than one (1) square mile, the above
analyses shall be submitted to IDOT /DWR
for approval.
(2) For a non - riverine floodplain, the
historic flood of record plus three feet
may be used for the BFE instead of
performing a detailed hydrologic and
hydraulic study.
d. Nothing contained herein shall prohibit the
application of these regulations to land that
can be demonstrated by engineering survey to
lie within any floodplain. Conversely, any
lands (except for those located in a
regulatory floodway) that can be demonstrated
by a topographic survey certified by a
registered professional engineer or
registered land surveyor to lie beyond the
floodplain, and to the satisfaction of the
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Enforcement Officer, to have been higher than
the base flood elevation as of the effective
date of the first regulatory floodplain map
denoting the site to be in a floodplain, or
for unmapped floodplains as of the effective
date of the Code, shall not be subject to the
regulations of this section.
In the case of a site located in the
regulatory floodway that is higher than the
BFE, it is subject to the regulations of this
section until such time as a letter of map
revision is received from the IDOT /DWR or its
designee or FEMA.
2. Performance Standards Applicable to all Floodplain
Development
The standards of this section apply to all
floodplain development except when superseded by
more stringent requirements in the subsequent
sections.
a. Modification and disturbance of natural
riverine floodplains shall be avoided to
protect existing hydrologic and environmental
functions. Such disturbances shall be
minimized and all negative impacts mitigated
as described in a mitigation plan.
b. No development shall be allowed in the
floodplain that shall singularly or
cumulatively 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
functions of the floodplain or channel.
C. For all projects involving channel
modification, fill, or levees, the flood
carrying capacity of the regulatory
floodplain shall be maintained. In addition,
the Enforcement Officer shall notify
potentially impacted communities, the SMC and
IDOT /DWR in writing 30 days prior to the
issuance of a permit for the modification or
relocation of the regulatory floodway or
flood conveyance path.
d. Compensatory storage is required for all lost
floodplain storage.
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(1) Hydraulically equivalent compensatory
storage requirements for fill or
structures in a riverine floodplain
shall be at least equal to 1.2 times the
volume of floodplain storage lost. Such
compensation areas shall be designed to
drain freely and openly to the
watercourse and located opposite or
adjacent to fill areas. The floodplain
volume lost below the existing 10 -year
frequency flood elevation must be
replaced below the proposed 10 -year
frequency flood elevation. The
floodplain volume lost above the 10 -year
existing frequency flood elevation must
be replaced above the proposed 10 -year
frequency elevation.
(2) Hydraulically equivalent compensatory
storage requirements for fill or
structures in a non - riverine floodplain
shall be at least equal to 1.0 times the
volume of floodplain storage lost.
e. Public Health Protection Standards
(1) No developments in the floodplain shall
include locating or storing chemicals,
explosives, buoyant materials, animal
wastes, fertilizers, flammable liquids,
pollutants, or other hazardous or toxic
materials below the FPE.
(2) New and replacement water supply
systems, wells, and sanitary sewer lines
may be permitted providing all manholes
or other above - ground openings located
below the Flood Protection Elevation
(FPE) are watertight.
f. Building Protection Requirements
(1) All new buildings, building alteration
that either increases the first floor
area by more than 20% or the building's
market value by more than 50 %, the
installation of a manufactured home on a
new site or a new manufactured home on
an existing site or installing a
recreational vehicle on a site for more
than 180 days and located within a 100 -
year floodplain shall be protected from
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flood damage below the flood protection
elevation.
(2) The lowest floor, including basements
for all new construction or substantial
improvements of residential structures
shall be two feet or more above the base
flood elevation.
(a) If placed on fill, the top of the
fill shall be above the flood
protection elevation. The fill
shall be placed at that elevation
for a distance of ten feet out from
the building unless the building
design is certified by a registered
structural engineer to be protected
from damages due to hydrostatic
pressures. Additionally, the fill
must be demonstrated not to settle
below the flood protection
elevation and to be adequately
protected against erosion, scour
and differential settlement.
(b) If elevated by means of walls,
pilings, or other foundation, the
building's supporting structure
must be 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
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 BFE. 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. All areas below the Flood
Protection Elevation shall be
constructed of materials resistant
to flood damage. The lowest floor
(including basement) and all
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Village of Deerfield
electrical, heating, ventilating,
plumbing, and air conditioning
equipment and utility meters shall
be located at or above the FPE.
Water and Sewer pipes, electrical
and telephone lines, submersible
pumps and other waterproofed
service facilities may be located
below the flood protection
elevation. No area below the flood
protection elevation shall be used
for storage of items or materials.
(3) The lowest floor including basement of
all new construction or substantial
improvements of non - residential
buildings shall be two feet or more
above the base flood elevations in
accordance with Article IV, Section
C.2.f(2) or be structurally dry flood
proofed. A nonresidential building may
be structurally dry floodproofed (in
lieu of elevation) provided that a
registered professional engineer or
structural engineer shall certify that
the building has been structurally dry
floodproofed below the flood protection
elevation and 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.)
(4) Manufactured homes and recreational
vehicles 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
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Illinois Mobile Home Tie -Down Act issued
pursuant to 77 Ill. Adm. Code 970.
(5) 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 flood or
100 -year frequency flood elevation
shall be constructed with
s waterproof material. Structures
located in a regulatory floodway
shall be constructed and placed on
a building site so as not to block
the flow of flood waters and shall
also meet the Appropriate Use
criteria of Article IV, Section
C.3. In addition, all other
requirements of this Code 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 $5,000 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.
(6) 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 Article IV, Section C.2.f.
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g. If the proposed development would result in a
change in the mapped regulatory floodplain or
100 -year frequency flood elevation on a site,
the applicant shall submit sufficient data to
obtain a Letter of Map Revision (LOMR) from
FEMA.
h. If the development is located in a public
body of water, as defined by IDOT /DWR, a
permit must also be received from IDOT /DWR.
i. Any work involving construction or
modification or removal of a dam or an on-
stream structure to impound water 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.
3. Additional Performance Standards for the
Regulatory Floodway (IDOT /DWR Regulations)
Only those appropriate uses listed below and in 92
Ill. Adm Code 708 will be allowed in the
regulatory floodway. 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. If the development is
proposed for the regulatory floodway portion of
the regulatory floodplain the following additional
standards apply in addition to the previously
stated standards for the floodplain:
a. Only the construction, modification, repair
or replacement of the following appropriate
uses will be allowed in the floodway:
(1) Public flood control structures and
private improvements relating to the
control of drainage and flooding of
existing buildings, erosion, water
quality or habitat for fish and
wildlife;
(2) Structures or facilities relating to
functionally water dependent uses such
as modifications or additions to
existing wastewater treatment
facilities;
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(3) Storm and sanitary sewer outfalls;
(4) Underground and overhead utilities if
sufficiently flood - proofed;
(5) 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;
(6) Detached garages, storage sheds, or
other nonhabitable structures without
toilet facilities, accessory to existing
buildings that will not block flood
flows nor reduce floodway storage.
(7) Bridges, culverts and associated
roadways, sidewalks and railways,
necessary for crossing over the floodway
or for providing access to other
appropriate uses in the floodway and any
modification thereto;
(8) Parking lots and any modifications
thereto (where the existing depth of
flooding for the BFE is less than one
foot) and aircraft parking aprons built
at or below ground elevation;
(9) Floodway regrading, without fill, to
create a positive non - erosive slope
toward a watercourse.
(10) Floodproofing activities to protect
previously existing lawful structures
including the construction of water-
tight window wells, elevating
structures, or the construction of flood
walls 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
to be substantial improvements to the
structure.
(11) The replacement, reconstruction or
repair of a damaged building, provided
that the outside dimension of the
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building are not increased and, provided
that, if the building is damaged to 50%
or more of the building's market value
before it was damaged, in which case it
shall conform to Article IV, Section
C.2.f.
(12) 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. No enclosed
floor areas may be build on stilts.
b. Additions to the above list of appropriate
uses are not allowed.
C. All appropriate uses shall require a Permit
from the Village Manager and must be in
accordance with all provisions of this Code.
d. Construction of an Appropriate Use will be
considered permissible provided that the
proposed project meets the following
engineering and mitigation criteria and that
of Article IV Sections C.1 and C.2 and is so
stated in writing with supporting plans,
calculations and data prepared by a
registered professional engineer.
(1) All effective regulatory floodway
conveyance lost due to the development
of Appropriate Uses, other than bridge
or culvert crossings or on- stream
structures or dams, shall 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:
(a) Regulatory floodway conveyance,
1.486
K = AR 213
n
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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.
(b) 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.
(2) Transition sections shall be provided
and used in calculations of effective
regulatory floodway conveyance, in the
design of excavations in the floodway,
between cross - sections with rapid
expansions and contractions, and when
meeting the regulatory floodway
delineation on adjacent properties. The
following expansion and contraction
ratios shall be used:
(a) Water will expand no faster than at
a rate of one foot horizontal for
every four feet of the flooded
stream's length.
(b) Water will contract no faster than
at a rate of one foot horizontal
for every one foot of the flooded
stream's length.
(c) Water will not expand or contract
faster than one foot vertical for
every ten feet of flooded stream
length.
(d) All cross - sections used in the
calculations shall be located
perpendicular to flood flows.
(e) In the design of excavations in the
floodway, erosion /scour protection
shall be provided on land upstream
and downstream of proposed
transition sections.
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(3) The development of all appropriate uses
shall not result in an increase in the
average channel or regulatory floodway
velocities or stage, for all flood
events up to and including the 100 -year
frequency event. However, 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 rip -rap or other
design measures.
(4) In the case of on- stream structures
built for the purpose of backing up
water, an increase in upstream stage
when compared to existing conditions for
all flood events up to and including the
100 -year frequency event shall be
contained within recorded easements. A
permit or letter indicating a permit is
not required must be obtained from
IDOT /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.
(5) If flood proofing construction is
required beyond the outside dimensions
of and existing habitable, residential
or commercial building, the outside
perimeter of the flood proofing
construction shall be placed no further
than 10 feet from the outside of the
building. Compensation of lost storage
and conveyance will not be required for
flood proofing activities.
(6) For public flood control projects, the
permitting requirements of this section
will be considered met if the applicant
can demonstrate to IDOT /DWR through
hydraulic and hydrologic calculation
that the proposed project will not
singularly or cumulatively result in
increased flood heights outside the
project right -of -way or easements for
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all flood events up to and including the
100 -year frequency event.
(7) General criteria for analysis of flood
elevations.
(a) The flood profiles, flows and
floodway data in the regulatory
floodway study, reference in
Article IV, Section C.1, must be
used for analysis of the base
conditions, If the study data
appears to be in error or
conditions have changed, IDOT /DWR
shall be contacted for approval and
concurrence on the appropriate base
conditions data to use.
(b) 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.
(c) If the applicant learns from
IDOT /DWR, local governments, or a
private owner that a downstream or
upstream 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 section for both the existing
conditions and the expected flood
profile conditions when the bridge,
culvert or flood control project is
built.
(8) If the appropriate use will result in a
change in the floodway location or BFE,
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the applicant shall submit sufficient
information to be issued a Conditional
Letter of Map Revision (CLOMR) from
IDOT /DWR and FEMA. A public notice
inviting public comment on the proposed
change in the BFE or location in the
floodway will be issued by IDOT /DWR or
its designee before a CLOMR is issued.
The application will not be considered
complete until the CLOMR is received.
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 Letter of Map
Revision (LOMR) is issued by IDOT /DWR
and FEMA.
e. For those circumstances listed below located
in a regulatory floodway, the following
information shall also be submitted to
IDOT /DWR or its designee for its concurrent
review and approval prior to the issuance of
a permit:
(1) Analysis of the flood profile due to a
proposed bridge, culvert crossings and
roadway approaches.
(2) An engineer's determination that an
existing bridge or culvert crossing or
approach road is not a source of flood
damage and the analysis indicating the
proposed flood profile.
(3) Alternative transition sections and
hydraulically equivalent storage.
(4) IDOT /DWR or its designee will review and
approve prior to the start of
construction any IDOT /DWR projects,
dams, etc. all other state, federal or
local projects and the projects of SMC.
4. Special Considerations for the Construction of New
Bridges or Culvert Crossings and Roadway
Approaches or the Reconstruction or Modification
of Existing Bridges, Culvert Crossings or Roadway
Approaches
a. The proposed structure shall not result in an
increase of upstream flood stages greater
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than 0.1 foot when compared to the existing
conditions for all flood events up to and
including the 100 -year frequency event unless
contained within the channel banks, project
right -of -way or recorded easements.
b. If the proposed construction will increase
upstream flood stages greater than 0.1 feet,
the developer must contact IDOT /DWR, Dam
Safety Section for a Dam Safety permit or
waiver.
C. Lost floodway storage
per the floodplain pe
this Code except that
storage lost due to a
behind a bridge shall
replaced, provided no
downstream.
must be compensated for
rformance standards of
artificially created
reduction in head loss
not be required to be
damage will be incurred
d. velocity increases must be mitigated per the
floodway performance section of this Code
except that 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 appropriate measures.
e. For modification of replacement of existing
structures, the existing structure must first
be evaluated in accordance with Department of
Transportation Rules 92 Ill. Adm. Code Part
708 to determine if the existing structure is
a source of flood damage and should be
redesigned. The evaluation must be submitted
to IDOT /DWR or its designee for review and
concurrence before a permit is issued.
f. 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.
g. The hydraulic analysis for the backwater
caused by the bridge showing the existing
condition and proposed regulatory profile
must be submitted to IDOT /DWR for concurrence
that a CLOMR is not required.
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5. Regulatory Floodplains without Regulatory
Floodways
Within all riverine floodplains where the floodway
has not been determined, the developer shall have
an engineering study performed to determine a
flood conveyance path to demonstrate that a
proposed development will have no singular or
cumulative impact on flood heights or velocities,
as required in Article IV, Section C.2.b. The
developer shall submit that engineering study to
SMC for review and acceptance prior to issuance of
a watershed development permit. In the case of
riverine floodplains draining greater than 1
square mile, it shall also be sent to IDOT /DWR or
its designee for review and approval. Upon
acceptance of their flood conveyance path by the
SMC, the developer can then choose to locate all
development activity outside of the flood
conveyance path or meet the performance standards
of Article IV, Section C, excluding the land use
restrictions of Article IV, Section C.3.a. Should
the flood conveyance path be determined so as to
include land not owned by the applicant, SMC shall
have the right to issue notice to the affected
property owners for comment before SMC approves
the flood conveyance path. The applicant may
limit the study to a floodplain determination and
apply the performance standards of Article IV,
Section C, excluding Section C.3.a to the entire
floodplain.
6. Application for Development in the Regulatory
Floodplain
If the development is located in a regulatory
floodplain, the applicant shall provide the
following additional information:
a. Site location of the property, drawn to scale
on the regulatory floodway map, indicating
whether it is proposed to be in an
incorporated or unincorporated area;
b. A plan view of the project showing:
(1) The regulatory floodway limit,
floodplain limit and for work in public
bodies of water as defined by IDOT /DWR,
the navigation channels.
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(2) 10 -year frequency flood elevation, 100 -
year frequency flood elevation and
graphic or numerical scales (horizontal
and vertical).
(3) A copy of the regulatory floodway
map, marked to reflect any proposed
change in the regulatory floodway
location.
C. A listing of all local, state and federal
permits or approval letters that may be
required for this type of development. All
required local, state and federal permits
must be received prior to permit issuance
unless otherwise agreed to between SMC and
the local, state and federal permitting
agency.
d. Engineering calculations and supporting data
shall be submitted showing that the proposed
work will meet the performance standards of
this Code.
e. All changes in grade resulting from any
proposed excavation or filling, and
floodplain and floodway limits; the location
and dimension 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 this
Code.
f. Elevation certificates of the lowest floor
(elevation including basements) or the
elevation to which a non - residential building
has been floodproofed using a floodproofing
certificate shall be required for all
buildings in the floodplain.
D. WETLAND PROVISIONS
In order to insure no net loss of the county's wetland
resources, the following provisions are required when 1
or more cumulative acres of wetland are impacted. The
provisions of this section regarding wetland submittal
requirements will not be executed by the SMC until such
time as a Memorandum Of Agreement or General Permit has
been issued by the U.S. Army Corps of Engineers.
1. Wetland Performance Standards
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a. The applicant shall delineate all wetland
area boundaries in accordance with the
current federal wetland determination
methodology.
b. A pre - application conference between the
Enforcement Officer and the applicant shall
be held to discuss proposed impacts,
mitigation options and submittal
requirements. Upon request by the Village of
Deerfield the SMC will provide technical
assistance at this conference.
C. The following hierarchy will be observed by
all applicants to determine application
requirements:
(1) The proposed project will avoid adverse
impacts to the greatest extent possible
based on consideration of hydrologic
conditions, existing topography,
vegetation and human activity as it
relates to stormwater management.
Wetlands of exceptional functional
value, as designated in the USEPA Lake
County Advanced Wetland Identification
Study (ADID), are considered to be
generally irreplaceable and
unmitigatable for the purposes of
evaluating permit applications.
(2) The proposed project will minimize the
adverse impacts to the greatest extent
possible based on consideration of
hydrologic conditions, water quality,
existing topography, vegetation and
human activity as it relates to
stormwater management.
(3) If there are wetland impacts, selection
of the appropriate mitigation option
will be based on a functional assessment
provided by the applicant.
d. Mitigation is required for all permanent
adverse impact to wetlands that result
despite attempts to avoid and /or minimize.
The following criteria shall be met to offset
the wetland impacts.
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(1) The mitigation plan shall include all
appropriate measures to be carried out
to maintain or improve the functions of
wetlands, mitigate adverse environmental
impacts, restore vegetation and land and
water features, prevent sedimentation
and erosion, minimize the area of
wetland disturbance and ensure
compliance with other provisions of this
Code.
(2) The mitigation will occur on -site unless
the functional assessment indicates that
the functions can easily be reproduced
off -site.
(3) Depending on the circumstances under
which wetlands are lost or disturbed,
the Enforcement Officer will determined
which of the following mitigation
options is appropriate.
(a) Restoration: Restoration refers to
actions performed on a site that
reverse or remedy adverse impacts.
(b) Enhancement: Enhancement refers to
actions performed to improve the
functionality of an existing,
degraded wetland.
(c) Creation: Creation refers to the
creation of new wetlands on a non -
wetland site.
(d) Contribution: Contribution refers
to the donation of land or money to
an SMC approved Wetland Mitigation
Bank.
(4) Mitigation standards shall be determined
by functional replacement. The
replacement of lost wetland functions,
as identified in the functional
assessment report shall be at a minimum
equal to those previous to disturbance.
The minimum land area ratio shall be 1.0
acre mitigated to every 1.0 acre lost.
A higher ratio may be required when the
probability of success of replacing the
lost functions warrant it.
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(5) All plants used in the mitigation shall
be native to the midwest.
(6) Performance standards shall be
established during the pre- application
conference and included in the
mitigation plan. The permittee shall
successfully implement the approved
mitigation plan or component within the
time period required by the Enforcement
Officer.
(7) Mitigation must be performed prior to or
concurrently with activities that will
permanently disturb wetlands.
e. Wetlands may be used for on -site stormwater
detention subject to the following:
(1) It must be demonstrated that the use of
the wetland for detention will maintain
or improve the wetland's beneficial
functions.
(2) Existing depressional storage in
wetlands shall be maintained and the
volume of detention storage provided to
meet the requirements of this Code shall
be in addition to the existing storage.
(3) No wetlands of exceptional functional
value shall be used for satisfying on-
site detention requirements.
f. Monitoring shall be utilized to insure the
establishment of the mitigation and that it
meets the standards of this Code. In order
to achieve this criterion, the following
standards shall be met:
(1) The permittee shall submit an annual
monitoring report for up to five years
from the completion of the construction
of the mitigation project. As part of
the final report the permittee shall
provide information justifying that
monitoring is no longer required. The
wetland establishment /monitoring period
shall be determined by the Enforcement
Officer.
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(2) The permittee shall consider monitoring
requirements fulfilled upon submittal of
the final report and subsequent receipt
of notice from the Enforcement Officer.
If the Enforcement Officer fails to send
notice to the permittee within 60 days
after receipt of the final report, the
monitoring requirements shall be
considered fulfilled.
(3) If at any time during the monitoring
period, inspections or data indicate
mitigation efforts are not succeeding,
the Enforcement Officer may require mid-
course corrections which may include re-
vegetation, removal of invasive species,
and /or controlled burns.
g. The permittee shall provide mechanisms to
insure the long -term protection of the
created, restored, or enhanced wetlands.
This may be achieved through protection
mechanisms including vegetative management,
deed restrictions, conservation easements, or
deeding the created, restored, or enhanced
wetlands to an organization or public agency
capable of protecting and maintaining the
wetland.
h. The Enforcement Officer shall provide
guidance to the applicant on the contents and
timing of the Mitigation Plan and shall
approve the plan prior to the Permit being
issued.
i. If a permit is required by the U.S. Army
Corps of Engineers, the permit application
shall be provided to the SMC for transmittal
to the Corps and concurrent review.
2. Application Requirements
All the following application requirements will be
required unless waived by the Enforcement Officer.
a. Wetland Determination Report
The applicant shall provide the following
information to the Enforcement Officer:
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(1) A map showing the exact location of
wetlands within the development
boundaries.
(2) An aerial photograph delineating
wetland, development and watershed
boundaries.
(3) Army Corps of Engineers data sheets with
representative color photographs shall
be provided for each wetland.
(4) A written description of the wetland(s)
including a complete functional
assessment.
b. Wetland Use
The applicant will provide documentation
regarding the following:
(1) Determination if the project is water
dependent and /or that no practicable
alternatives to the impacts exists.
(2) Minimization of unavoidable impacts to
the maximum extent possible.
(3) Selection and justification of an
appropriate mitigation option.
(4) Appropriate use of wetlands for
detention.
C. Wetland Mitigation Plan
A mitigation plan shall include all of the
following information:
(1) Names, addresses and telephone numbers
of the principals associated with
implementation of the mitigation plan.
(2) A description of the mitigation project,
including best management practices
proposed as fulfillment of the required
replacement of lost wetland acreage and
functions. The description shall
include project location maps showing
the geographic relationship between the
proposed mitigation sites.
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(3) Plan view scaled drawings that include
mitigation project locations,
topography, cross - sections, stockpile
areas, erosion and sediment control
practices, equipment and supply storage
areas.
(4) A construction schedule that includes
starting and completion dates.
(5) Hydrologic analysis that includes normal
and 100 -year surface elevations and
estimated seasonal water surface
elevations.
(6) The scientific and common name of plant
species used in the mitigation plan
along with their planting location,
spacing, propagule type, commercial
source of planting stock, planting
density, and planting method.
(7) The permittee shall provide the
Enforcement Officer with access to the
mitigation site during business hours.
d. Monitoring Plan
(1) In order to insure the establishment of
the wetland mitigation, the applicant
shall provide the Enforcement Officer
with a monitoring plan that;
(a) identifies the names, addresses,
and phone numbers of parties
responsible for management; and
(b) states the management techniques,
schedule, and funding mechanisms.
(2) An annual monitoring report shall
include the following information:
(a) A description of how the mitigation
project meets the mitigation
standards.
(b) Photographs of the mitigation
project.
(c) A description of any mid - course
corrections taken or that need to
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be taken to
mitigation
mitigation
e. Long -Term Maintenance
implement the
plan to meet the
standards.
(1) The applicant shall provide
documentation to the Enforcement Officer
regarding who will be responsible for
the long -term maintenance and protection
of the wetland(s). This documentation
shall include:
(a) The names, addresses, and phone
numbers of parties responsible for
maintenance.
(b) Types of preservation mechanisms
used such as deed restrictions or
conservation easements.
(2) The drainage facility maintenance
provisions (Article IV, Section
B.2.b.(9) of the Code applies to
restored, enhanced, or created wetlands.
E. PUBLIC ROADWAY DEVELOPMENT PERMIT
1. Authority and Enforcement
a. The SMC shall be responsible for the review
and enforcement of all Public Road
Developments Permits.
2. Application Requirements
a. A copy of any applicable Illinois Department
of Transportation - Division of Water
Resources Permit application.
b. A copy of any applicable Illinois Department
of Conservation /Illinois Department of
Transportation Agency Action Plan Wetland
Permit application.
C. A copy of the proposed Stormwater Management
System, including the location and size of
all existing and proposed drainage
improvements including plan, section, and
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profile views of storm sewers, field tiles,
culverts, channels, and detention areas.
d. A copy of all calculations supporting the
stormwater management system. Material should
be consistent with the requirements of
Article IV, Section B.2.b(5).
e. A Soil Erosion and Sediment Control Plan
consistent with Article IV, Section B.l.j.
f. A Wetland Determination Report and Mitigation
Plan consistent with Article IV, Section D,
if applicable.
Article V: VARIANCES AND APPEALS
A. VARIANCES
The Enforcement Officer upon application, after
hearing, and subject to the process and standards that
follow, may grant variances to the provisions of this
Code as will not cause detriment to the public good,
safety or welfare nor be contrary to the spirit,
purpose and intent of this Code where, by reason of
unique and exceptional physical circumstances or
condition of a particular property, the literal
enforcement of the provisions of this Code would result
in an unreasonable hardship.
1. The Enforcement Officer shall administer the
variance provisions.
2. For Public Road Developments, the SMC Chief
Engineer shall administer the variance provisions.
3. A public notice will be issued inviting public
comment on all proposed variances to major
development performance standards. A copy of the
public notice will be sent to SMC.
4. Variances shall be granted only upon:
a. showing of good and sufficient cause, and
b. a determination that the variance is the
minimum necessary to afford relief,
considering the flood hazard and water
quality, and
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C. a finding that failure to grant the variance
would result in exceptional hardship to the
applicant, and
d. a finding that the granting of a variance
would not result in increased flood heights,
additional threats to public safety, or
extraordinary public expense, nor create
nuisances, cause fraud or victimization of
the public, nor conflict with existing local
laws or ordinances and that all buildings
will be protected by methods that minimize
flood damage during the base flood elevation,
and
e. a finding that the development activity can
not be located outside the floodplain, and
f. a determination that the activity is not in a
regulatory floodway.
5. Upon consideration of the factors noted above and
the intent of the Code, the Enforcement Officer
may attach such conditions to the granting of a
variance deemed necessary to further the purposes
and objectives herein.
6. Variances requested in connection with restoration
of a historic site or historic structure, may be
granted using criteria more permissive than the
requirements of this section, subject to the
conditions that the repair or rehabilitation is
the minimum necessary to preserve the historic
character and design of the structure and the
repair or rehabilitation will not result in the
structure being removed as a certified historic
structure.
7. The Enforcement Officer shall notify an applicant
in writing that a variance from the requirements
of Article IV.C.2.f. that would lessen the degree
of protection to a building will result in
increased premium rates for flood insurance up to
amounts as high as $25 for $100 of insurance
coverage, increase the risks to life and property,
and require that the applicant will acknowledge in
writing the assumption of the risks and liability.
8. In a regulatory floodplain without a regulatory
floodway that drains greater than one square mile,
a variance may not be granted that will result in
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a loss of the floodplain storage of greater than
10% of the existing floodplain storage on the
site.
9. Variances requested in connection with the
redevelopment of previously developed sites, that
will further the public policy goals of downtown
redevelopment and neighborhood revitalization, may
be granted a variance provided the variance would
not result in an increase in the pre - redevelopment
runoff rate or volume and there will exist
adequate downstream stormwater capacity.
10. Written findings shall be made public for all
findings on Variances and shall be on file with
the SMC.
B. APPEALS:
1. Any person aggrieved by a decision the Enforcement
Officer may request review thereof by the Village
of Deerfield board of elected officials or the
appropriate body.
2. Any person aggrieved by a variance decision of the
SMC Chief Engineer may request review thereof by
the SMC Director.
3. Any person aggrieved by a decision, requirement,
ruling or interpretation of this Code by the SMC
Director may appeal it to the SMC by written
notice filed with the SMC Director within 10 days
of the determination.
Article V: INSPECTIONS AND ACCESS
Representatives of the SMC or the Village of Deerfield are
authorized to enter upon any land or water to inspect
development activity.
Article VII: WATERSHED DEVELOPMENT RECORDS
The adopted Lake County Comprehensive Stormwater Management
Plan states the SMC should "maintain a repository of
stormwater management data for the county." Toward that
end, the Enforcement Officer shall:
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A. Maintain records of every Watershed Development Permit
application, permit, variance, hydrologic and hydraulic
data and enforcement action as well as "as- built" plans
if available, for a period of at least 5 years from the
date of permit issuance and shall allow periodic
inspections of the records by SMC personnel.
B. Maintain a jurisdiction map which displays the
development location and file reference number of every
permit. Collect and maintain elevation and
floodproofing certificates for all new buildings in the
regulatory floodplain. Where the development site was
located above the BFE prior to development, maintain
documentation of the pre- development ground elevations
and certification that the ground elevations existed
prior to the effective date of the first regulatory
floodplain map.
C. Provide to SMC staff a copy of each variance granted,
elevation or flood - proofing certificate issued and
other permit related materials upon reasonable request
by SMC staff.
D. Transfer to SMC, at agreed upon intervals, but no later
than the 5 -year period described above, specified
portions of the stormwater records.
E. SMC will maintain a "Master" map displaying the
development location and file reference number of all
Watershed Development Permits thus, will be requesting
this information of the Village of Deerfield.
Article VIII: PENALTIES AND LEGAL ACTIONS
A. Whenever an Enforcement Officer finds a violation of
this Code, or of any permit or order issued pursuant
thereto, within their respective jurisdiction, the
Enforcement Officer may issue a stop work order on all
development activity on the subject property or on the
portion of the activity in direct violation of the
Code. In every case, the Enforcement Officer shall
issue an order that (1) describes the violation (2)
specifies the time period for remediation and (3)
requires compliance with the Code prior to the
completion of the activity in violation.
B. Failure to comply with any of the requirements of this
Code shall constitute a violation, and any person
convicted thereof shall be fined not more than five
hundred ($500.00) dollars for each offense. Each day
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the violation continues shall be considered a separate
offense.
C. The Village Manager may also take any other legal
action necessary to prevent or remedy any violation
including appropriate equitable or injunctive relief
and, if applicable, an assessment to the violator for
the removal, correction, or termination of any adverse
effects upon any property resulting from any
unauthorized activity for which legal action under this
section may have been brought.
D. The Village Clerk may record a notice of violation on
the title to the property.
E. The Enforcement Officer 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.
Article IX: DISCLAIMER OF LIABILITY
It is recognized that although the degree of flood
protection required by this Code is considered reasonable
for regulatory purposes and is based on scientific and
engineering considerations, on occasions greater floods can
and will occur, and flood heights may be increased by man-
made or natural causes. These provisions do not imply that
land outside the flood -plain areas or that uses permitted
within such areas will be free from flooding or flood
damages. These provisions shall not create liability on the
part of the Stormwater Management Commission nor the Village
of Deerfield nor any officer or employee thereof for any
flood damages that result from reliance on this Code or any
administrative decision lawfully made thereunder.
Article X: SEPARABILITY
The provisions of this Code shall be deemed separable and
the invalidity of any portion of this Code shall not affect
the validity of the remainder.
Article XI: EFFECTIVE DATE
The effective date of this Code shall be the day of
1992.
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Adequate Downstream
facility shall be ci
stormwater capacity
up to and including
increasing property
downstream known to
causing significant
APPENDIX A
DEFINITIONS
Stormwater Capacity: A stormwater management
Dnsidered to have adequate downstream
if the facility can be shown to accommodate
the 100 -year stormwater runoff without
damage to the adjacent property or to a point
the Enforcement Officer to be a restriction
backwater.
Applicant: Any person, firm or governmental agency who owns
property or the duly appointed representative and wishes to
develop that property and one who executes the necessary forms to
procure permit to carry out such development from the SMC or
Certified Community.
Appropriate Use: Permissible development within the regulated
floodway that will be considered for permit issuance.
Base Flood Elevation (BFE): The elevation delineating the level
of flooding resulting from the 100 -year flood frequency
elevation.
Basin plan: A study and evaluation of an individual drainage
basin's stormwater management and flood control needs.
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
recreational vehicles to be installed on a site for more than 180
days.
Buffer: An area of predominantly vegetated land to be left open,
adjacent to drainageways, wetland, lakes, ponds or other surface
waters for the purpose of eliminating or minimizing adverse
impacts to such areas.
Certified Community: A community which has petitioned the SMC
and has been found by the SMC to be capable of enforcing an
ordinance (or Codes) which contain stormwater and floodplain
management rules and regulations which are consistent with or at
least as stringent as these of this Lake County Watershed
Development Ordinance.
Channel: A natural or artificial watercourse of perceptible
extent which periodically or continuously contains moving water,
or which forms a connection link between two bodies of water. It
has a definite bed and banks which serve to confine the water.
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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 bottom or woody vegetation. Channel
modification does not includes the clearing of dead or dying
vegetation, debris, or trash from the channel. Channelization is
a severe form of channel modification typically involving
relocation of the existing channel (e.g., straightening).
Community: Any municipality (as defined at Ill. Rev. Stat.,
1989, Ch. 24, 1 -1 -2 (1) or the unincorporated county within Lake
County acting as a unit of local government.
Compensatory storage: An excavated, hydraulically equivalent
volume of storage used to offset the loss of natural flood
storage capacity when artificial fill or structures are placed
within a floodplain.
Conditional Approval Regulatory Floodway Map Change:
Preconstruction approval by IDOT /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 (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 plans
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 storing or diverting water or creating a pool.
Underground water storage tanks are not included.
Damage: Measurable rise in flood heights on buildings currently
subject to flooding, flooding of buildings currently not subject
to flooding and increases in volume or velocity to the point
where the rate of land lost to erosion and scour is substantially
increased.
Depressional storage areas: Non - riverine depressions in the earth
where stormwater collects.
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Design storm: A selected storm event, described in terms of the
probability of occurring once within a given number of years, for
which stormwater or flood control improvements are designed and
built.
Detention Facility: A man made structure for the temporary
storage of stormwater runoff with controlled release during or
immediately following a storm.
Development: Finalization of a plat, replat, lot -split or man-
made change to real estate by private or public agencies
including:
A. Construction, reconstruction, repair, or placement of a
building or any addition to a building;
B. Installation of a manufactured home on a site,
preparation of a site for a manufactured home, or the
placement of a recreational vehicle on a site for more
than 180 days;
C. Drilling, mining, installation of utilities,
construction of roads, bridges, or similar projects;
D. Clearing of land as an adjunct of construction;
E. Construction or erection of levees, walls, fences,
dams, or culverts; channel modification; filling,
dredging, grading, excavating, paving, or other
alterations of the ground surface; storage of
materials; deposit of solid or liquid waste;
F. Any other activity that might change the direction,
height, volume or velocity of flood or surface water,
including the drainage of wetlands and removal of
vegetation to the extent such that the wetland would no
longer meet the criteria of supporting hydrophytic
vegetation as defined in this Code except that which
would be considered appropriate for management
purposes.
Development does not include repair, remodelling or maintenance
of existing buildings and facilities as defined in Appendix A of
this Code, or gardening, plowing, and similar agricultural
practices that do not involve filling, grading, or construction
of levees. Nor does development include agricultural practices
outside of the floodplain involving filling or grading as part of
a SCS designed and approved conservation project (ie. terraces,
grass waterways). Additionally, development does not include
fence installation, pole placement, drilling or other minor
auxiliary construction activity which does not effect stormwater
runoff rates or volumes as long as the development activity is
not located in a floodplain, wetland or watercourse.
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Stormwater Management Code
Village of Deerfield
Direct discharge: Discharges of stormwater which have not passed
through a detention or retention facility designed to the
specification of this Code.
Drainage Area: The land area above a given point that contributes
stormwater to that point.
Dry Detention Facility: A dry detention facility is a detention
facility designed to drain completely after temporary storage of
stormwater flows and to normally be dry over the majority of its
bottom area.
Elevation certificates: A form published by the Federal Emer-
gency Management Agency that is used to certify the elevation to
which a building has been elevated.
Enforcement Officer: The Village Manager or the person
designated by the Village Manager.
Erosion: The process whereby soil is removed by flowing water or
wave action.
Exceptional Functional Value Wetland: Any wetland identified as
such in the USEPA Advanced Identification Study of Lake county
(ADID) or any wetland that through a functional assessment meets
the criteria defined in that study for determining exceptional
functional value.
Fee -in -Lieu of On -Site Detention: A fee assessed to a permit
applicant used to contribute to the cost of the capital
improvement component of basin plans; such as, regional detention
site(s) or improvements to downstream conveyances "in- lieu -of"
constructing on -site detention.
FEMA: Federal Emergency Management Agency and its regulations.
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 of runoff of
surface waters from any source.
Flood conveyance path: The channel, including onstream lakes,
and that portion of the floodplain adjacent to a stream or
watercourse, which is needed to convey the existing and
anticipated future 100 -year frequency flood discharge with no
more than a 0.1 foot increase in stage.
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.
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Stormwater Management Code
Village of Deerfield
Flood Insurance Rate Maps (FIRM): A map prepared by the Federal
Emergency Management Agency or HUD 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 (regulatory): Floodplains may be either riverine or
non - riverine depressional areas. Riverine floodplains are those
areas contiguous to a lake, pond, or stream whose elevation is
greater than the normal water pool elevation but equal to or
lower than the projected 100 -year flood elevation. Non - riverine
floodplains are depressional storage areas not associated with a
stream system which surrounding lands drain causing periodic
inundation by storm waters. In certain cases, the floodplain may
also be known as the Special Flood Hazard Area (SFHA). A
regulatory floodplain exists along any watercourse draining 100
acres or more or any non - riverine areas with a surface area
greater than 1/4 acre for the 100 year event.
Floodplain Management: An overall program of corrective and
preventive measures for avoiding or reducing future flood damage.
Flood Protection Elevation (FPE )-: The elevation of the base
flood or 100 -year frequency flood plus 2 feet of freeboard at any
given location in the Special Flood Hazard Area (SFHA).
Floodproofing: Any combination of structural and non - structural
additions, changes or adjustments to structures or property 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.
Floodway (regulatory): The channel, including onstream lakes, and
that portion of the floodplain adjacent to a stream or water-
course as designated by the Illinois Department of Transpor-
tation, Division of Water Resources, 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.
Freeboard: An increment of height added to the base flood eleva-
tion to provide a factor of safety for uncertainties in calcula-
tions, unknown local conditions, wave actions and unpredictable
effects such as those caused by ice or debris jams.
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Stormwater Management Code
Village of Deerfield
Functional Assessment: An assessment of a wetlands flood
storage, water quality and other beneficial functions.
Historic Structure: A "Historic Structure" is any structure that
is:
A. Listed individually in the National Register of
Historic Places or preliminarily determined by the
Secretary of the Interior as meeting the requirements
for individual listing on the National Register;
B. Certified or preliminarily determined by the Secretary
of the Interior as contributing to the historic
district or a district preliminarily 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; or
D. Individually listed on a local inventory of historic
places that has been certified by the Illinois Historic
Preservation Agency.
Hydraulically Equivalent Compensatory Storage: Compensatory
storage placed between the proposed normal water elevation and
the proposed 100 -year flood elevation. All storage lost below
the existing 10 -year flood elevation is replaced below the
proposed 10 -year flood elevation. All storage lost above the
existing 10 -year flood elevation is replaced above the proposed
10 -year flood elevation.
Hydric soil: A soil that is saturated, flooded, or ponded long
enough during the growing season to develop an anaerobic
conditions in the upper part.
Hydrologically Disturbed: An area where the land surface has
been modified to increase runoff, volumes, rates, or direction.
Hydrophytic vegetation: Plant life growing in water, soil or on a
substrate that is at least periodically deficient in oxygen as a
result of excessive water content.
IDOT /DWR: Illinois Department of Transportation, Division of
Water Resources (also IDOT -DWR).
Impervious surface: Any hard - surfaced, man made area that does
not readily absorb or retain water, including but not limited to
building roofs, parking and driveway areas, graveled areas,
sidewalks and paved recreation areas.
Lake: A natural or artificial body of water encompassing an area
of two or more acres which retains water throughout the year.
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Stormwater Management Code
Village of Deerfield
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 Flood Insurance
Rate Map (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 connected to
the required utilities. The term manufactured homes also include
park trailers, recreational vehicles and other similar vehicles
installed 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.
Mitigation: Measures taken to eliminate or minimize damage from
development activities, such as construction in wetlands or
floodplain filling, by replacement of the resource or other means
of compensation.
NGVD: National Geodetic Vertical Datum of 1929.
Natural: When used in reference to streams and channels means
those streams and channels formed by the existing surface
topography of the earth prior to changes made by man. A modified
stream and channel which has regained natural characteristics
over time as it meanders and reestablishes vegetation may be con-
sidered natural.
Non - riverine floodplain: Floodplains not associated with streams,
creeks or rivers, such as isolated depressional storage areas.
Ownership Parcel: Any legally described parcel of land. This
includes contiguous lots or parcels of land owned by the same
property owner.
Ordinary high water mark: The point on the bank or shore at which
the presence and movement of surface waters are continuous so as
to leave a distinctive mark, such as by erosion, destruction or
prevention of terrestrial vegetation, predominance of aquatic
vegetation, or other such recognized characteristics.
Parcel Identification Number: Permanent index number used to
identify properties for tax assessment.
Stormwater Management Code
Village of Deerfield
Pond: A natural or artificial body of water of less than two
acres which retains water year round.
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, structures and property. The
project 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 road development: Any development activity which takes
place in a highway right -of -way or part thereof that is adminis-
tered and funded by a public agency under its respective highway
jurisdiction. Rehabilitative maintenance and in -kind replacement
are not considered to be a public road development and do not
require a permit, unless located in a regulatory floodway.
Reconstruction: The act of rebuilding a structure.
Registered Professional Engineer: An engineer registered in the
State of Illinois, under the Professional Engineer Practice Act
of 1989 (III. Rev. Stat. 1989, ch. 111, pars. 5201 - 5249).
Regulatory Floodplain: See Floodplain (regulatory)
Regulatory Floodway: See Floodway (regulatory)
Repair, remodeling or maintenance: 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 Facility: A facility designed to completely retain a
specified amount of stormwater runoff without release except by
means of evaporation, infiltration or pumping.
Riverine: Relating to, formed by, or resembling a stream (includ-
ing creeks and rivers).
Sedimentation: The processes that deposit soils, debris, and
other materials either on other ground surfaces or in bodies of
water or watercourses.
SMC Director: The administrative head of the staff of the Lake
County Stormwater Management Commission.
Special Flood Hazard Area (SFHA): Any base flood area subject to
flooding from a river, creek, stream, or any other identified
channel or ponding and shown on a Flood Hazard Boundary Map or
Flood Insurance Rate Map as Zone A, A0, Al -30, AE, A99, AH, VO,
V30, VE, V, M, or E.
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Stormwater Management Code
Village of Deerfield
Stormwater Management: A set of actions taken to control storm -
water runoff with the objectives of providing controlled surface
drainage, flood control and pollutant reduction in runoff.
Stormwater Management Commission (SMQ : The Lake County
Stormwater Management Commission established and existing under
Ill. Rev. Statutes, Chapter 34, Par. 5 -1062 for the purposes of
developing, revising and implementing a countywide stormwater
management plan.
Stormwater Management System: The collection of natural features
and man -made facilities which define the stormwater management
for a development.
Stream: A course of running water flowing in a channel (includes
creeks and rivers).
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 recreational vehicle
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
improvements of 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 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.
Water Dependent: Structures of facilities relating to the use
of, or requiring access to, the water or shoreline. Examples of
water dependent uses include but are not limited to pumping
facilities, wastewater treatment facilities, facilities and
improvements related to recreation boating or commercial
shipping.
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Stormwater Management Code
Village of Deerfield
Watercourse: Any natural or man -made depression into which water
flows either regularly or intermittently draining an area of 20
acres or more.
Watershed: The land area above a given point on a watercourse
that contributes stormwater to that point. In Lake County the
four major watersheds are officially defined as: the Lake
Michigan Watershed, the North Branch of the Chicago River
Watershed, the Des Plaines River Watershed, and the Fox River
Watershed.
Watershed Development Permit: A permit established by this Code
and issued, through the SMC or certified communities, prior to
the approval of a building permit signifying approval of
procedures identified for stormwater control, floodplain develop-
ment, wetlands development and mitigation, and water quality
protection.
Wet Detention Facility: A wet detention facility designed to
maintain a permanent pool of water after the temporary storage of
stormwater runoff.
Wetland: Land that is inundated or saturated by surface or
ground water at a frequency and duration sufficient to support,
under normal conditions, a prevalence of vegetation adapted for
life in saturated soil conditions (known as hydrophytic vegeta-
tion). A wetland is identified based upon the three attributes:
1) hydrology, 2) soils and 3) vegetation as mandated by the
current Federal wetland determination methodology. To aid in
determining the presence or absence of wetlands, the following
courses of information may be used:
A. Lake County Wetland Inventory, Lake County Department
of Management Services;
B. National Wetland Inventory, U.S. Fish and Wildlife
Service;
C. Lake County Soil Survey, U.S. Department of
Agriculture -Soil Conservation Service;
D. U.S. Geological Survey Topographic Maps;
E. Consultant study or Lake County Soil and Water
Conservation District Natural Resource Opinion.
The above sources of information are not in hierarchical order
and are to be used only to aid in determining the approximate
location of wetlands. Use of such off -site maps or references is
not intended to substitute for an on -site delineation.
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APPENDIX B
SMC REGULATORY FLOODPLAIN MAPS AND PROFILES
COMMUNITY WATERWAY MAP TYPE MAP DATE DESCRIPTION
COMMUNITY NAME
DEERFIELD
APPENDIX C
FEMA FLOOD INSURANCE STUDY MAPS AND PROFILES
COMMUNITY MEMBER
170361C
DATE OF CURRENT
EFFECTIVE MAP
(OR MAP INDEX)
AUG 04, 1988
FIS STUDY
DATE
AUG 04, 1988
APPENDIX D
IDOT /DWR DESIGNATED REGULATORY FLOODWAY MAPS
COMMUNITY WATERWAY
MAP TYPE MAP DATE DESCRIPTION
DEERFIELD MID. FORK N. BR.
CHICAGO RIVER REG 01/01/75 NB- 25,26,27: 33600
FT. to 47050 FT.
ABOVE MOUTH AND
48500 FT. TO 50300
ABOVE MOUTH.
i0will1a llm -1.11!
CHICAGO RIVER REG 01/01/75 NB- 39,40,41: 44350
FT. ABOVE MOUTH TO
MONTGOMERY DRIVE
(LAKE -COOK CORPORATE
LIMITS TO LAKE
ELEANOR)