For the purposes of this Chapter, the following definitions are adopted and shall apply whether or not the defined words and phrases are capitalized:
ACCESSORY STRUCTURE: A non-habitable Building, used only for parking of vehicles or storage, that is on the same parcel of property as the principal Building and the use of which is incidental to the use of the principal Building.
ACT: An act in relation to the regulation of the rivers, lakes, and streams of the State of Illinois, 615 ILCS 5/5 et seq.
AGRICULTURAL STRUCTURE: A walled and roofed structure used exclusively for agricultural purposes or uses in connection with the production, harvesting, storage, raising, or drying of agricultural commodities and livestock, including aquatic organisms. Structures that house tools or equipment used in connection with these purposes or uses are also considered to have agricultural purposes or uses.
APPLICANT: Any person, firm, corporation, or agency that applies for a Floodplain Development permit.
APPROPRIATE USES: Only uses of the Designated Floodway that are permissible and will be considered for permit issuance. The only uses that will be allowed are as specified in Section 4-12-6(B) of this Chapter.
ASCE: American Society of Civil Engineers
BASE FLOOD: The Flood having a one-percent chance of being equaled or exceeded in any given year. The Base Flood is often referred to as the 100year flood.
BASE FLOOD ELEVATION (BFE): The height in relation to the North American Vertical Datum (NAVD) of 1988 (or other datum, where specified) of the crest of the Base Flood. Application of the BFE at any location is as defined in Section 4-12-4 of this Chapter.
BASEMENT: Any area of the building, including any sunken room or sunken portion of a room, having its floor below ground level (subgrade) on all sides.
BUILDING: A walled and roofed Building, including gas or liquid storage tank, that is principally above ground, including Manufactured Homes and prefabricated buildings. The term also includes Recreational Vehicles and travel trailers installed on a site for more than one hundred and eighty (180) consecutive days.
CHANNEL: Any river, stream, creek, brook, branch, natural or artificial depression, ponded area, flowage, slough, ditch, conduit, culvert, gully, ravine, wash, or natural or man-made drainageway, which has a definite bed and banks or shoreline, in or into which surface or groundwater flows, either perennially or intermittently.
CHANNEL MODIFICATION: Alteration of a Channel by changing the physical dimensions or materials of its bed or banks. Channel Modification includes Damming, riprapping (or other armoring), widening, deepening, straightening, relocating, lining and significant removal of native vegetation from the bottom or banks. Channel Modification does not include the clearing of dead or dying vegetation, debris, or trash from the Channel. Channelization is a severe form of Channel Modification involving a significant change in the Channel cross-section and typically involving relocation of the existing Channel (e.g. straightening).
COMPENSATORY STORAGE: An artificially excavated, hydraulically equivalent volume of storage within the Floodplain used to balance the loss of natural Flood storage capacity when artificial fill or Structures are placed within the Floodplain. The uncompensated loss of natural Floodplain storage can increase off-site floodwater elevations and flows.
CONDITIONAL APPROVAL OF A DESIGNATED FLOODWAY MAP CHANGE: Preconstruction approval by IDNR/OWR and FEMA of a proposed change to the Floodway map. This preconstruction approval, pursuant to 17 Ill. Adm. Code Part 3708, 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 providing FEMA's comment on a proposed project that would, upon construction, affect the hydrologic or hydraulic characteristics of a flooding source and thus result in the modification of the existing Designated Floodway, the effective BFEs, or the Floodplain.
CRITICAL FACILITY: Any facility which is critical to the health and welfare of the population and, if flooded, would create an added dimension to the disaster. Damage to these Critical Facilities can impact the delivery of vital services, can cause greater damage to other sectors of the community, or can put special populations at risk.
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. Dams may also include weirs, restrictive culverts, or impoundment Structures. Underground water storage tanks are not included.
DESIGNATED FLOODWAY: The channel, including on-stream lakes, and that portion of the Floodplain adjacent to a stream or watercourse, generally depicted on the FEMA FIRM map, which is needed to store and convey the existing Base 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 ten percent (10%) increase in velocities.
A. The Floodways are designated for on the countywide FIRM of Cook County prepared by FEMA and dated August 19, 2008. When two Floodway maps exist for a waterway, the more recent effective Floodway limit shall prevail.
B. The Floodways for those parts of unincorporated Cook County that are within the extraterritorial jurisdiction of the Village that may be annexed into the Village are designated on the countywide FIRM of Cook County prepared by FEMA and dated August 19, 2008.
C. To locate the Designated Floodway boundary on any site, the Designated Floodway boundary should be scaled off the FIRM map and located on a site plan, using reference marks common to both maps. Where interpretation is needed to determine the exact location of the Designated Floodway boundary, IDNR/OWR should be contacted for the interpretation.
DEVELOPMENT: Any man-made change to real estate, including:
A. Construction, reconstruction, repair, or placement of a Building or any addition or improvement to a Building;
B. Substantial Improvement of an existing Building;
C. Installing a Manufactured Home on a site, preparing a site for a Manufactured Home, or installing a travel trailer or Recreational Vehicle on a site for more than one hundred and eighty (180) consecutive days;
D. Installing utilities, construction of roads, bridges, or similar projects;
E. Demolition of a Building, re-development of a site, clearing of land as an adjunct of construction;
F. Construction or erection of levees, walls, fences, Dams, culverts, or Channel Modification;
G. Filling, dredging, grading, excavating, paving, drilling, mining, or other non-agricultural alterations of the ground surface;
H. Storage of materials including the placement of gas and liquid storage tanks, and any other activity that might change the direction, height, or velocity of Flood or surface waters;
I. Any other activity of man that might change the direction, height, or velocity of Flood or surface water, including extensive vegetation removal;
J. Development does not include such activities as re-surfacing of pavement when there is no increase in elevation, or gardening, plowing, and similar agricultural practices that do not involve filling, grading, or construction of levees.
ELEVATION CERTIFICATES: A form published by FEMA that is used to certify the elevation to which a Building has been elevated.
FEMA: Federal Emergency Management Agency and its regulations at 44 CFR 59-79, as amended.
FLOOD: A general and temporary condition of partial or complete inundation of normally dry land areas from overflow of inland or tidal waters, or from the unusual and rapid accumulation or runoff of surface waters from any source. Flood also includes the collapse or subsidence of land along the shore of a lake or other body of water as a result of erosion or undermining caused by waves or currents of water exceeding anticipated cyclical levels or suddenly caused by an unusually high water level in a natural body of water, accompanied by a severe storm, or by an unanticipated force of nature, such as flash Flood or an abnormal tidal surge, or by some similarly unusual and unforeseeable event which results in a general and temporary condition of partial or complete inundation of normally dry land areas from the overflow of inland or tidal waters.
FLOOD FREQUENCY: A period of years, based on a statistical analysis, during which a Flood of a stated magnitude may be expected to be equaled or exceeded.
FLOOD FRINGE: That portion of a Zone A or Zone AE Floodplain that is outside of the Floodway.
FLOOD INSURANCE RATE MAP (FIRM): A map prepared by FEMA that depicts the Floodplain or Special Flood Hazard Area within a community. This map includes insurance rate zones and Floodplains and may or may not depict Floodways and show BFE.
FLOOD INSURANCE STUDY (FIS): An examination, evaluation, and determination of Flood hazards and if appropriate, corresponding water surface elevations.
FLOODPLAIN:
A. The Floodplains are those lands within the jurisdiction of the Village that are subject to inundation by the Base Flood. The Floodplains of the Village are generally identified as such on panel numbers of the countywide FIRM for Cook County as prepared by the FEMA and dated August 19, 2008.
B. The Floodplains of those parts of unincorporated Cook County that are within the extraterritorial jurisdiction of the Village or that may be annexed into the Village and that are subject to inundation by the Base Flood. The Floodplains are generally identified as such on panel numbers 17031C0387J, 17031C0389J and 17031C0395J of the countywide FIRM for Cook County by the FEMA and dated August 19, 2008.
FLOODPROOFING: Any combination of structural and non-structural additions, changes or adjustments to Buildings that reduce or eliminate Flood damage to real estate or improved real property, water and sanitary facilities, Buildings, and their contents.
FLOODPROOFING CERTIFICATE: A form published by FEMA that is used to certify the elevation to which a Building has been designed and constructed to be structurally dry floodproofed.
FLOOD PROTECTION ELEVATION (FPE): The greater of: 1) the elevation of the Base Flood (or depth) plus one foot of Freeboard, or 2) when required by the MWRD, the elevation of the Base Flood (or depth) plus two feet of Freeboard at any given location in the Floodplain.
FLOODWAY: See Designated Floodway.
FREEBOARD: An increment of elevation added to the BFE to provide a factor of safety for uncertainties in calculations, future watershed Development, unknown localized conditions, wave actions and unpredictable effects such as those caused by ice or debris jams.
HISTORIC STRUCTURE: Any Building 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 of the Interior to qualify as a registered historic district;
C. Individually listed on the State inventory of historic places by the Illinois Historic Preservation Agency;
D. Individually listed on a local inventory of historic places that has been certified by the Illinois Historic Preservation Agency.
IDNR/OWR: Illinois Department of Natural Resources, Office of Water Resources.
IDNR /OWR JURISDICTIONAL STREAM: IDNR/OWR has jurisdiction over any stream serving a tributary area of 640 acres or more in an urban or urbanizing area, or in the floodway of any stream serving a tributary area of 6,400 acres or more in a rural area. Construction on these streams requires a permit from the IDNR/OWR (17 Ill. Adm. Code Part 3700 or Part 3708). The IDNR/OWR may grant approval for specific types of activities by issuance of a statewide permit or a regional permit.
LETTER OF MAP AMENDMENT (LOMA): Official determination by FEMA that a specific Building, area of land or a parcel of land, where there has not been any alteration of the topography since the date of the first NFIP map showing the property within the Floodplain, was inadvertently included within the Floodplain and that the Building, area of land or a parcel of land is removed from the Floodplain.
LETTER OF MAP REVISION (LOMR): Letter that revises BFEs, Floodplains or Floodways as shown on an effective FIRM.
LOWEST FLOOR: The lowest floor of the lowest enclosed area (including Basement). An unfinished or flood-resistant enclosure usable solely for parking of vehicles, building access or storage, in an area other than a Basement area is not considered a building's lowest floor; provided that such enclosure is not built so as to render the Building in violation of the applicable non-elevation design requirements of this Chapter.
MANUFACTURED HOME: A Building, transportable in one or more sections, which is built on a permanent chassis and is designated for use with or without a permanent foundation when attached to the required utilities. The term Manufactured Home does not include a Recreational Vehicle.
MANUFACTURED HOME PARK OR SUBDIVISION: A parcel (or contiguous parcels) of land divided into two or more Manufactured Home lots for rent or sale.
NEW CONSTRUCTION: New Construction means Buildings for which the Start of Construction commenced on or after the effective date of a Floodplain management regulation adopted by a community and includes any subsequent improvements to such Buildings.
NEW MANUFACTURED HOME PARK OR SUBDIVISION: Manufactured Home park or subdivision for which the construction of facilities for servicing the lots on which the Manufactured Homes are to be affixed (including at a minimum, the installation of utilities, the construction of streets, and either final site grading or the pouring of concrete pads) is completed on or after the effective date of the Village of River Forest's initial Floodplain management regulations.
NAVD 88: North American Vertical Datum of 1988. NAVD 88 supersedes the National Geodetic Vertical Datum of 1929 (NGVD).
PUBLIC BODY OF WATER: All open public streams and lakes capable of being navigated by watercraft, in whole or in part, for commercial uses and purposes, and all lakes, rivers, and streams which in their natural condition were capable of being improved and made navigable, or that are connected with or discharge their waters into navigable lakes or rivers within, or upon the borders of the State of Illinois, together with all bayous, sloughs, backwaters, and submerged lands that are open to the main Channel or body of water directly accessible thereto, as identified in 17 Ill. Adm. Code Part 3704.
PUBLIC FLOOD CONTROL PROJECT: A flood control project which will be operated and maintained by a public agency to reduce flood damages to existing buildings and structures, including 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.
RECREATIONAL VEHICLE OR TRAVEL TRAILER: A vehicle which is:
A. Built on a single chassis;
B. Four hundred (400) square feet or less when measured at the largest horizontal projection;
C. Designed to be self-propelled or permanently towable by a light duty truck; and
D. Designed primarily not for use as a permanent dwelling but as temporary living quarters for recreational, camping, travel, or seasonal use.
REGIONAL PERMITS: Regional Permits are offered for pre-approved projects which are considered minor projects that are permissible per 17 Ill. Adm. Code Part 3708 rules for Northeastern Illinois Designated Floodways. A complete listing of the terms and conditions for specific project types can be obtained from the IDNR/OWR website.
REGISTERED LAND SURVEYOR: A land surveyor registered in the State of Illinois, under the Illinois Land Surveyors Act, 225 ILCS 330/1, et seq.
REGISTERED OR LICENSED PROFESSIONAL ENGINEER (P.E.): An engineer registered in the State of Illinois, under the Illinois Professional Engineering Practice Act, 225 ILCS 325/1 et seq.
REPETITIVE LOSS: Flood-related damages sustained by a Building on two separate occasions during a 10-year period for which the cost of repairs at the time of each such Flood event, on the average, equals or exceeds 25 percent of the market value of the Building before the damaged occurred.
RETENTION/DETENTION FACILITY: A retention facility stores stormwater runoff without a gravity release. A detention facility provides for storage of stormwater runoff and controlled release of this runoff during and after a Flood or storm.
RIVERINE FLOODPLAIN: Any Floodplain subject to flooding from a river, creek, intermittent stream, ditch, on-stream lake system or any other identified Channel. This term does not include areas subject to flooding from lakes, ponding areas, areas of sheet flow, or other areas not subject to overbank flooding.
START OF CONSTRUCTION: Includes Substantial Improvement and means the date the Building permit was issued, provided the actual Start of Construction, repair, reconstruction, rehabilitation, addition placement or other improvement, was within 180 days of the permit date. The actual start means the first placement of permanent construction of a Building on a site, such as the pouring of slab or footings, the installation of piles, the construction of columns or any work beyond the stage of excavation, including the placement of a Manufactured Home on a foundation. For a Substantial Improvement, actual Start of Construction means the first alteration of any wall, ceiling, floor, or other structural part of a Building whether or not that alteration affects the external dimensions of the Building.
STATEWIDE PERMITS: Statewide permits are offered for pre-approved projects that are considered minor projects which are permissible per the IDNR/OWR Part 3700 rules. A complete listing of the statewide permits and permit requirements can be obtained from the IDNR/OWR website.
STRUCTURE: The results of a man-made change to the land constructed on or below the ground, including a Building any addition to a Building; installing utilities, construction of roads or similar projects; construction or erection of levees, walls, fences, bridges or culverts; drilling, mining, filling, dredging, grading, excavating; and the storage of materials.
SUBSTANTIAL DAMAGE: Damage of any origin sustained by a Building whereby cost to repair the building to its before damaged condition equals or exceeds 50 percent of the market value of the Building before the damage occurred, regardless of actual repair work performed. The term includes flood related damages sustained by a Building on two separate occasions in a ten (10)-year period, in which the cost of the repairs, on average, equals or exceeds twenty-five percent (25%) of the market value of the Building at the time of each such flood event.
SUBSTANTIAL IMPROVEMENT: Any reconstruction, rehabilitation, addition, or improvement of a Building taking place during a five (5)-year period in which the percentage of improvements, figured cumulatively by dividing the cost of each improvement by the market value of the Building prior to the start of construction of each improvement, equals or exceeds fifty percent (50%).
A. 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 Building. This term includes Buildings which have incurred Repetitive Loss or Substantial Damage, regardless of the actual work done.
B. The term does not, however, include either:
1. any project for improvement of a Building to correct existing violations of state or local health, sanitary, or safety code specifications which have been identified by the local code enforcement official and which are solely necessary to assure safe living conditions; or
2. Any alteration of a Historic Structure listed on the National Register of Historic Places or the Illinois Register of Historic Places, provided that the alteration will not preclude the Building's continued designation as a Historic Structure.
TRANSITION SECTION: Reaches of the stream or Floodway where water flows from a narrow cross-section to a wide cross-section or vice versa.
VIOLATION: The failure of a Structure or other development to be fully compliant with this Chapter. (Ord. 3852, 1-10-2022)