1. To meet the requirements of 615 Illinois Compiled Statutes 5/4.9, "an act in relation to the regulation of the rivers, lakes and streams of the state of Illinois", approved June 10, 1911, as amended;
2. To assure that new development does not increase the flood or drainage hazards to others, or creating unstable conditions susceptible to erosion;
3. To protect new buildings and major improvements from flood damage;
4. To protect human life and health from the hazards of flooding;
5. To lessen the burden on the taxpayer for flood control projects, repairs to flood damaged public facilities and utilities, and flood rescue and relief operations;
6. To make federally subsidized flood insurance available for property in the Village by fulfilling the requirements of the national flood insurance program;
7. To comply with the rules and regulations of the national flood insurance program codified as 44 CFR 59-79, as amended;
8. To protect, conserve, and promote the orderly development of land and water resources;
9. To preserve the natural hydrologic and hydraulic functions of watercourses and floodplains and to protect water quality and aquatic habitats;
10. To preserve the natural characteristics of stream corridors in order to moderate flood and storm water impacts, improve water quality, reduce soil erosion, protect aquatic and riparian habitat, provide recreational opportunities, provide aesthetic benefits and enhance community and economic development. (Ord. 08-28, 8-11-2008)
    

1. Construction, reconstruction, repair, or placement of a building or any addition to a building.
2. Installing a manufactured home on a site, preparing a site for a manufactured home, or installing a travel trailer on a site for more than one hundred eighty (180) days.
3. Drilling, mining, installing utilities, construction of roads, bridges, or similar projects.
4. Demolition of a structure and/or redevelopment of a site.
5. Construction or erection of levees, walls, fences, dams or culverts, filling, dredging, grading, excavating, paving or other nonagricultural alterations of the ground surfaces; storage of materials.
6. Any other activity of man that might change the direction, height, or velocity of flood or surface water. Development does not include maintenance of existing buildings and facilities such as reroofing or resurfacing of roads when there is no increase in elevation, or gardening, plowing, and similar agricultural practices that do not involve filling, grading, or construction of levees.

ELEVATION CERTIFICATES: A form published by the federal emergency agency that is used to certify the elevation to which a building has been elevated.

EROSION: The general process whereby soils are moved by flowing water or wave action.

EXEMPT ORGANIZATIONS: Organizations which are exempt from this chapter per the Illinois Compiled Statutes including state, federal or local units of government; or others such as the water reclamation district and the Cook County forest preserve district.

FEMA: Federal emergency management agency and its regulations at 44 CFR 59-79, effective as of October 1, 1986. This incorporation does not include any later editions or amendments.

FLOOD: A general and temporary condition of partial or complete inundation of normally dry land areas from overflow of inland or tidal waves, or the unusual and rapid accumulation or runoff of surface waters from any source.

FLOOD FREQUENCY: A period of years, based on a statistical analysis, during which a flood of a stated magnitude may be expected to be equaled or exceeded.

FLOOD FRINGE: That portion of the floodplain outside of the designated floodway.

FLOOD INSURANCE RATE MAPS (FIRM): A map prepared by the federal emergency management agency that depicts the special flood hazard area (SFHA) within a community. This map includes insurance rate zones and floodplains and may or may not depict floodways.

FLOOD INSURANCE STUDY (FIS): An examination and evaluation of hydrologic and hydraulic data sponsored by the federal insurance administration to determine base flood flows, elevations, areas, and floodways. The FIS also determines flows, elevations, and areas of floods having lesser and greater frequencies of occurrence than the base flood.

FLOOD PROFILE: Graphical representations of the elevations of the water surface of the 100-year flood along the watercourses of the Village.

FLOOD PROTECTION ELEVATION (FPE): The elevation of the base flood or 100-year frequency flood plus one foot (1') of freeboard at any given location in the SFHA.

FLOODPLAIN: That land typically adjacent to a body of water with ground surface elevations at or below the base flood or the 100-year frequency flood elevation. Floodplains may also include detached special flood hazard areas, ponding areas, etc. The floodplain is also known as the special flood hazard area (SFHA). The floodplains are those lands within the jurisdiction of the Village that are subject to inundation by the base flood or 100-year frequency flood. The SFHAs of the Village are generally identified as such on map number 17031C, panels 0237, 0241, 0242, 0243, 0244, all dated August 19, 2008, of the countywide flood insurance rate map for Cook County prepared by the federal emergency management agency.

FLOODPROOFING: Any combination of structural and nonstructural additions, changes or adjustments to structures which reduce or eliminate flood damage to real estate or improved real property, water and sanitary facilities, structures and their contents.

FLOODPROOFING CERTIFICATES: 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 ENCROACHMENT LINES: The lateral boundaries of the floodway which separate it from the flood fringes.

FREEBOARD: An increment of elevation added to the base flood elevation to provide a factor of safety for uncertainties in calculations, unknown localized conditions, wave actions and unpredictable effects such as those caused by ice or debris jams.

HYDROLOGIC AND HYDRAULIC CALCULATIONS: Engineering analysis which determines expected flood flows and flood elevations based on land characteristics and rainfall events.

HYDROSTATIC UPLIFT: The upward pressure exerted on floor slabs or an entire structure by standing or ground water, which tends to float a structure or crack the floor. It is based on the difference in elevation between the surface level of the water. Hydrostatic pressure may be horizontal, imposing forces on the walls causing them to crack or fail.

IDNR/DWR: Illinois department of natural resources, division of water resources.

LETTER OF MAP AMENDMENT (LOMA): Official determination by FEMA that a specific structure is not in a 100-year flood zone; amends the effective flood hazard boundary map 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 includes park trailers, travel trailers and other similar vehicles placed on site for more than one hundred eighty (180) consecutive days.

MANUFACTURED HOME PARK OR SUBDIVISION: A parcel (or contiguous parcels) of land divided into two (2) or more manufactured home lots for rent or sale.

MITIGATION: Includes those measures necessary to minimize the negative effects which floodplain development activities might have on the public health, safety and welfare. Examples of mitigation include compensatory storage, soil erosion and sedimentation control, and channel restoration.

NGVD: National geodetic vertical datum of 1929. Reference surface set by the national geodetic survey deduced from a continental adjustment of all existing adjustments in 1929.

100-YEAR FLOOD: A flood magnitude with a one percent (1%) statistical chance of being equaled or exceeded during any year. However, the occurrence of such an event does not diminish the chance of it recurring again at any time.

PUBLIC FLOOD CONTROL PROJECT: A flood control project which will be operated and maintained by a public agency to reduce flood damages to existing buildings and structures which includes a hydrologic and hydraulic study of the existing and proposed conditions of the watershed. Nothing in this definition shall preclude the design, engineering, construction or financing, in whole or in part, of a flood control project by persons or parties who are not public agencies.

PUBLICLY NAVIGABLE WATERS: All streams and lakes capable of being navigated by watercraft.

REGISTERED LAND SURVEYOR: A land surveyor registered in the state of Illinois, under the Illinois land surveyors act ¹.

REGISTERED PROFESSIONAL ENGINEER: An engineer registered in the state of Illinois, under the Illinois professional engineering act ².

REPAIR, REMODELING OR MAINTENANCE: Development activities which do not result in any increases in the outside dimensions of a building or any changes to the dimensions of a structure.

RISK PREMIUM RATES ZONE: Flood hazard areas designated according to the degree of flooding they would experience during the base flood. The symbols used to designate these zones are as follows:

1. Area of special flood hazard without water surface elevations determined.
   
   A1-99: Area of special flood hazard with water surface elevations determined.
   
   AH: Area of special flood hazards having a level water surface (ponding) with water depths between one foot (1') and three feet (3').
   
   AO: Area of special flood hazards having a sloping water surface (sheet runoff) with water depths between one foot (1') and three feet (3').
   
   VO: Area of special flood hazards having shallow water depths and/or unpredictable flow paths between one foot (1') and three feet (3') and with velocity.
2. Area of moderate flood hazards.
3. Area of minimum hazards.

RIVERINE SFHA: Any SFHA 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.

SPECIAL FLOOD HAZARD AREA (SFHA): Any base flood area subject to flooding from a river, creek, intermittent stream, ditch, or any other identified channel or ponding and shown on a flood hazard boundary map or flood insurance rate map as zone A, AO, A1-30, AE, A99, AH, VO, V3O, VE, V, M, or E.

STRUCTURE: The results of a manmade 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; anything constructed or erected, the use of which requires permanent or temporary location on or in the ground; installing a manufactured home on a site; preparing a site for a manufactured home or installing a travel trailer on a site for more than one hundred eighty (180) days.

SUBSTANTIAL IMPROVEMENT: Any repair, reconstruction or improvement of a structure, the cost of which equals or exceeds fifty percent (50%) of the market value of the structure either: a) before the improvement or repair is started, or b) if the structure has been damaged, and is being restored, before the damage occurred. For the purposes of this definition "substantial improvement" is considered to occur when the first alteration of any wall, ceiling, floor, or other structural part of the building commences, whether or not that alteration affects the external dimensions of the structure. The term does not, however, include either: a) 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 b) 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.

WATERCOURSE: Any river, stream, creek, brook, branch or other drainageway in or into which stormwater runoff and floodwaters flow either regularly or intermittently. (Ord. 08-28, 8-11-2008)

¹ 225 ILCS.
² 225 ILCS.

1. No variance shall be granted unless the applicant demonstrates that:
   1. The development activity cannot be located outside the SFHA;
   2. An exceptional hardship would result if the variance were not granted;
   3. The relief requested is the minimum necessary;
   4. There will be no additional threat to public health, safety, beneficial stream uses and functions, especially aquatic habitat, or creation of a nuisance;
   5. There will be no additional public expense for flood protection, lost environmental stream uses and functions, rescue or relief operations, policing, or repairs to streambeds and banks, roads, utilities, or other public facilities;
   6. The provisions of subsections 12-14-7E and 12-14-8D of this chapter shall still be met;
   7. The activity is not in a designated floodway;
   8. The applicant's circumstances are unique and do not represent a general problem; and
   9. The granting of the variance will not alter the essential character of the area involved including existing stream uses.
2. The zoning board of appeals shall notify an applicant in writing that a variance from the requirements of section 12-14-9 of this chapter that would lessen the degree of protection to a building will:
   1. Result in increased premium rates for flood insurance up to amounts as high as twenty five dollars ($25.00) for one hundred dollars ($100.00) of insurance coverage:
   2. Increase the risks to life and property; and
   3. Require that the applicant proceed with knowledge of these risks and that he will acknowledge in writing that he assumes the risk and liability.
3. Variance requested in connection with restoration of site or building listed on the National Register of Historical Places or documented as worthy of preservation by the Illinois historic preservation agency may be granted using criteria more permissive than the requirements of subsections 12-14-10A and B of this chapter. (Ord. 08-28, 8-11-2008)
   

1. The base flood or 100-year frequency flood elevation for the SFHAs of the north branch of the Chicago River shall be as delineated on the 100-year flood profiles in the countywide flood insurance study for Cook County prepared by the federal emergency management agency and dated August 19, 2008, including amendments to such study and maps as may be prepared from time to time.
2. The base flood or 100-year frequency flood elevation for each of the remaining SFHAs delineated as an "A zone" on the flood insurance rate map of the Village shall be according to the best existing data available in the Illinois state water survey floodplain information repository. When no base flood or 100-year frequency flood elevation exists, the base flood or 100-year frequency flood elevation for a riverine SFHA shall be determined from a backwater model, such as HEC-II, WSP-2, or a dynamic model such as HIP. The flood flows used in the hydraulic models shall be obtained from a hydrologic model, such as HEC-1, TR-20 or HIP, or by techniques presented in various publications prepared by the United States geological survey for estimating peak flood discharges. Flood flows should be based on anticipated future land use conditions in the watershed as determined from adopted local and regional land use plans. Along any watercourses draining more than one square mile, the above analyses shall be submitted to IDNR/DWR for approval. Once approved it must be submitted to the Illinois state water survey floodplain information repository for filing. For a nonriverine SFHA, the base flood elevation shall be the historic flood of record plus three feet (3'), unless calculated by a detailed engineering study and approved by the Illinois state water survey. (Ord. 08-28, 8-11-2008)
   

1. Development Permit: No person, firm, corporation, or governmental body not exempted by state law shall commence any development in the SFHA without first obtaining a development permit from the building commissioner.
2. Application: Application for a development permit shall be made on a form provided by the building commissioner. The application shall be accompanied by drawings of the site, drawn to scale, showing property line dimensions and legal description for the property and sealed by a licensed engineer, architect or land surveyor; existing grade elevations in MSL (1929 adjustment) datum or NGVD and all changes in grade resulting from excavation or filling; the location and dimensions of all buildings and additions to buildings. For all proposed buildings, the elevation of the lowest floor (including basement) and lowest adjacent grade shall be shown on the submitted plans and the development will be subject to the requirements of section 12-14-9 of this chapter.
3. Elevation Comparison: Upon receipt of a development permit application, the building commissioner shall compare the elevation of the site to the base flood or 100-year frequency flood elevation. Any development located on land that can be shown to have been higher than the base flood elevation as of the site's first flood insurance rate map identification is not in the SFHA and, therefore, not subject to the requirements of this chapter. The building commissioner shall maintain documentation of the existing ground elevation at the development site and certification that this ground elevation existed prior to the date of the site's first flood insurance rate map identification.
4. Other Documents: The building commissioner shall be responsible for obtaining from the applicant, copies of all other local, state and federal permits, approvals or permit not required letters that may be required for this type of activity. The building commissioner shall not issue a permit unless all other local, state and federal permits have been obtained.
5. Preventing Increased Damages: No development in the flood fringe shall create a threat to public health and safety.
6. Site Elevation; LOMR: If fill is being used to elevate the site above the base flood or 100-year frequency flood elevation, the applicant shall submit sufficient data and obtain a letter of map revision (LOMR) from FEMA for the purpose of removing the site from the floodplain.
7. Compensatory Storage: Whenever any portion of a floodplain is authorized for use, the volume of space which will be occupied by the authorized fill or structure below the base flood or 100-year frequency flood elevation shall be compensated for and balanced by a hydraulically equivalent volume of excavation taken from below the base flood or 100-year frequency flood elevation. The excavation volume shall be equal to 1.1 times the volume of storage lost due to the fill or structure.
8. Fill Or Structure: In the case of streams and watercourses, such excavation shall be made opposite or adjacent to the areas so filled or occupied. All floodplain storage lost below the existing 10-year flood elevation shall be replaced below the proposed 10-year flood elevation. All floodplain storage lost above the existing 10-year flood elevation shall be replaced above the proposed 10-year flood elevation. All such excavations shall be constructed to drain freely and openly to the watercourse. (Ord. 08-28, 8-11-2008)
   

1. Development Permit: No person, firm, corporation or governmental body not exempted by state law shall commence any development in a floodway without first obtaining a development permit from the building commissioner.
2. Application: Application for a development permit shall be made on a form provided by the building commissioner. The application shall include the following information:
   1. Name and address of applicant;
   2. Site location (including legal description) of the property, drawn to scale, on the designated floodway map, indicating whether it is proposed to be in an incorporated or unincorporated area;
   3. Name of stream or body of water affected;
   4. Description of proposed activity;
   5. Statement of purpose of proposed activity;
   6. Anticipated dates of initiation and completion of activity;
   7. Name and mailing address of the owner of the subject property if different from the applicant;
   8. Signature of applicant or the applicant's agent;
   9. If the applicant is a corporation, the president or other authorized officer shall sign the application form;
   10. If the applicant is a partnership, each partner shall sign the application form; and
   11. If the applicant is a land trust, the trust officer shall sign the name of the trustee by him(her) as trust officer. A disclosure affidavit shall be filed with the application, identifying each beneficiary of the trust by name and address and defining the respective interests therein;
   12. Plans of the proposed activity shall be provided which include as a minimum:
       1. A vicinity map showing the site of the activity, name of the waterway, boundary lines, names of roads in the vicinity of the site, graphic or numerical scale, and north arrow;
       2. A plan view of the project and engineering study reach showing existing and proposed conditions including principal dimensions of the structure of work, elevations in mean sea level (1929 adjustment) datum or NGVD, adjacent property lines and ownership, drainage and flood control easements, location of any channels and any existing or future access roads, distance between proposed activity and navigation channel (when the proposed construction is near a commercially navigable body of water), designated floodway limit, floodplain limit, location and orientation of cross sections, north arrow, and graphic or numerical scale;
       3. Cross section views of the project and engineering study reach showing existing and proposed conditions including principal dimensions of the work as shown in plan view, existing and proposed elevations, normal water elevation, 10-year frequency flood elevation, 100-year frequency flood elevation, and graphic or numerical scales (horizontal and vertical);
       4. A copy of the designated floodway map, marked to reflect any proposed change in the designated floodway location;
   13. Any and all other local, state and federal permits or approval letters that may be required for this type of development.
   14. Engineering calculations and supporting data shall be submitted showing that the proposed work will meet the permit criteria of subsections D and E of this section.
   15. If the designated floodway delineation, base flood or 100-year frequency flood elevation will change due to the proposed project, the application will not be considered complete until IDNR/DWR has indicated conditional approval of the regulatory floodway map change. No structures may be built until a letter of map revision has been approved by FEMA.
   16. The application for a structure shall be accompanied by drawings of the site, drawn to scale, showing property line dimensions and existing ground elevations and all changes in grade resulting from any proposed excavation or filling, and floodplain and floodway limits; sealed by a registered professional engineer, licensed architect or registered land surveyor; the location and dimensions of all buildings and additions to buildings; and the elevation of the lowest floor (including basement) of all proposed buildings subject to the requirements of section 12-14-9 of this chapter.
3. Other Documents: The building commissioner shall be responsible for obtaining from the applicant copies of all other local, state, and federal permits and approvals that may be required for this type of activity. The building commissioner shall not issue the development permit unless all required federal and state permits have been obtained.
   
   A professional engineer under the employ or contract of the Village shall review and approve applications reviewed under this section.
4. Preventing Increased Damages; List Of Appropriate Uses: The only development in a floodway which will be allowed are appropriate uses which will not cause a rise in the base flood elevation, and which will not create a damaging or potentially damaging increase in flood heights or velocity or be a threat to public health and safety. Only those appropriate uses listed in 92 Illinois administrative code 708 will be allowed. Appropriate uses do not include the construction or placement of any new structures, fill, building additions, buildings on stilts, fencing (including landscaping or planting designed to act as a fence) and storage of materials except as specifically defined above as an appropriate use. The approved appropriate uses are as follows:
   
   Additions to existing buildings above the BFE that do not increase the building's footprint and are valued at less than fifty percent (50%) of the market value of the building;
   
   Bridges, culverts, roadways, sidewalks, railways, runways and taxiways and any modification thereto;
   
   Designated floodway regrading, without fill, to create a positive nonerosive slope toward a watercourse;
   
   Detached garages, storage sheds, or other nonhabitable accessory structures without toilet facilities to existing buildings that will not block flood flows, nor reduce floodway storage;
   
   Flood control structures, dikes, dams and other public works or private improvements relating to the control of drainage, flooding, erosion, or water quality or habitat for fish and wildlife;
   
   Floodproofing activities to protect previously existing lawful structures including the construction of watertight window wells, elevating structures, or construction of floodwalls around residential, commercial or industrial principal structures where the outside toe of the floodwall shall be no more than ten feet (10') away from the exterior wall of the existing structure, and, which are not considered substantial improvements to the structure;
   
   In the case of damaged or replacement buildings, reconstruction or repairs made to a building that are valued at less than fifty percent (50%) of the market value of the building before it was damaged or replaced, and which do not increase the outside dimensions of the building;
   
   Parking lots and any modifications thereto (where depth of flooding at the 100-year frequency flood event will not exceed 1.0 foot) and aircraft parking aprons built at or below ground elevation;
   
   Recreational facilities such as playing fields and trail systems including any related fencing (at least 50 percent open when viewed from any one direction) built parallel to the direction of flood flows, and including open air pavilions;
   
   Storm and sanitary sewer outfalls;
   
   Structures or facilities relating to the use of, or requiring access to, the water or shoreline, such as pumping and treatment facilities, and facilities and improvements related to recreational boating, commercial shipping and other functionally water dependent uses;
   
   Underground and overhead utilities.
5. Engineering Criteria: Within the regulatory floodway as identified on the designated floodway maps designated by IDNR/DWR, the construction of an appropriate use, will be considered permissible provided that the proposed project meets the following engineering criteria and is so stated in writing with supporting plans, calculations and data by a registered professional engineer and provided that any structure meets the protection requirements of section 12-14-9 of this chapter.
   1. Preservation Of Flood Conveyance, So As Not To Increase Flood Stages Upstream: For appropriate uses other than bridge or culvert crossings, on stream structures or dams, all effective regulatory floodway conveyance lost due to the project will be replaced for all flood events up to and including the 100-year frequency flood. In calculating effective designated floodway conveyance, the following factors shall be taken into consideration:
      1. Designated floodway conveyance,
         
         "K" = 1.486 AR^2/3
         n
         
         where "n" is Manning's roughness factor, "A" is the effective area of the cross section, and "R" is the ratio of the area to the wetted perimeter. (See "Open Channel Hydraulics", Ven Te Chow, 1959, McGraw-Hill Book Company, New York.)
      2. The same Manning's "n" value shall be used for both existing and proposed conditions unless a recorded maintenance agreement with a federal, state, or local unit of government can assure the proposed conditions will be maintained or the land cover is changing from a vegetative to a nonvegetative land cover.
      3. Transition sections shall be provided and used in calculations of effective designated floodway conveyance. The following expansion and contraction ratios shall be used unless an applicant's engineer can prove to IDNR/DWR through engineering calculations or model tests that more abrupt transition may be used with the same efficiency.
         1. When water is flowing from a narrow section to a wider section, the water should be assumed to expand no faster than at a rate of one foot (1') horizontal for every four feet (4') of the flooded stream's length.
         2. When water is flowing from a wide section to a narrow section, the water should be assumed to contract no faster than at a rate of one foot (1') horizontal for every one foot (1') of the flooded stream's length.
         3. When expanding or contracting flows in a vertical direction, a minimum of one foot (1') vertical transition for every ten feet (10') of stream length shall be used.
         4. Transition sections shall be provided between cross sections with rapid expansions and contractions and when meeting the designated floodway delineation on adjacent properties.
         5. All cross sections used in the calculations shall be located perpendicular to flood flows.
   2. Preservation Of Floodway Storage So As Not To Increase Downstream Flooding: Compensatory storage shall be provided for any designated floodway storage lost due to the proposed work from the volume of fill or structures placed and the impact of any related flood control projects. Compensatory storage for fill or structures shall be equal to at least 1.1 times the volume of floodplain storage lost. Artificially created storage lost due to a reduction in head loss behind a bridge shall not be required to be replaced. The compensatory designated floodway storage shall be placed between the proposed normal water elevation and the proposed 100-year flood elevation. All designated floodway storage lost below the existing 10-year flood elevation shall be replaced below the proposed 10-year flood elevation. All designated floodway storage lost above the existing 10-year flood elevation shall be replaced above the proposed 10-year flood elevation. All such excavations shall be constructed to drain freely and openly to the watercourse. If the compensatory storage will not be placed at the location of the proposed construction, the applicant's engineer shall demonstrate to IDNR/DWR through a determination of flood discharges and water surface elevations that the compensatory storage is hydraulically equivalent. Finally, there shall be no reduction in floodway surface area as a result of a floodway modification, unless such modification is necessary to reduce flooding at the existing structure.
   3. Preservation Of Floodway Velocities So As Not To Increase Stream Erosion Or Flood Heights: For all appropriate uses, except bridges or culverts or on stream structures, the proposed work will not result in an increase in the average channel or designated floodway velocities. 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 riprap or other design measures.
   4. Construction Of New Bridges Or Culvert Crossings And Roadway Approaches: The proposed structure shall not result in an increase of upstream flood stages greater than 0.1 foot when compared to the existing conditions for all flood events up to and including the 100-year frequency event; or the upstream flood stage increases will be contained within the channel banks (or within existing vertical extensions of the channel banks) such as within the design protection grade of existing levees or flood walls or within recorded flood easements. If the proposed construction will increase upstream flood stages greater than 0.1 foot, the developer must contact IDNR/DWR, dam safety section for a dam safety permit or waiver.
      1. The engineering analysis of upstream flood stages must be calculated using the flood study flows, and corresponding flood elevations for tailwater conditions for the flood study specified in section 12-14-6 of this chapter. Culverts must be analyzed using the U.S. DOT, FHWA hydraulic chart for the selection of highway culverts. Bridges must be analyzed using the U.S. DOT/federal highway administration hydraulics of bridge waterways calculation procedures.
      2. Lost floodway storage must be compensated for per subsection E2 of this section.
      3. Velocity increases must be compensated for per subsection E3 of this section.
      4. 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.
      5. All excavations for the construction of the crossing shall be designed per subsection E8 of this section.
      6. The hydraulic analysis for the backwater caused by the bridge showing the existing condition and proposed regulatory profile must be submitted to IDNR/DWR for concurrence that a CLOMR is not required per this subsection and subsection D of this section.
   5. Reconstruction Or Modification Of Existing Bridges, Culverts, And Approach Roads:
      1. The bridge or culvert and roadway approach reconstruction or modification shall be constructed with no more than 0.1 foot increase in backwater over the existing flood profile for all flood frequencies up to and including the 100-year event, if the existing structure is not a source of flood damage.
      2. If the existing bridge or culvert and roadway approach is a source of flood damage to buildings or structures in the upstream floodplain, the applicant's engineer shall evaluate the feasibility of redesigning the structure to reduce the existing backwater, taking into consideration the effects on flood stages on upstream and downstream properties.
      3. The determination as to whether or not the existing crossing is a source of flood damage and should be redesigned must be prepared in accordance with the department of transportation rules 92 Illinois administrative code 708 (floodway construction in northeastern Illinois) and submitted to the division of water resources for review and concurrence before a permit is issued.
   6. On Stream Structures Built For The Purpose Of Backing Up Water: Any increase in upstream flood stages greater than 0.0 foot when compared to the existing conditions, for all flood events up to and including the 100-year frequency event shall be contained within the channel banks (or within existing vertical extensions of the channel banks) such as within the design protection grade of existing levees or floodwalls or within recorded flood easements. A permit or letter indicating a permit is not required must be obtained from IDNR/DWR, dam safety section for a dam safety permit or waiver for any structure built for the purpose of backing up water in the stream during normal or flood flow. All dams and impoundment structures as defined in section 12-14-3 of this chapter shall meet the permitting requirements of 92 Illinois administrative code 702 (construction and maintenance of dams). If the proposed activity involves a modification of the channel or floodway to accommodate an impoundment, it shall be demonstrated that:
      1. The impoundment is determined to be in the public interest by providing flood control, public recreation, or regional stormwater detention;
      2. The impoundment will not prevent the migration of indigenous fish species, which require access to upstream areas as part of their life cycle, such as for spawning;
      3. The impoundment will not cause or contribute to degraded water quality or habitat conditions. Impoundment design should include gradual bank slopes, appropriate bank stabilization measures, and a presedimentation basin;
      4. A nonpoint source control plan has been implemented in the upstream watershed to control the effects of sediment runoff as well as minimize the input of nutrients, oil and grease, metals, and other pollutants. If there is more than one municipality in the upstream watershed, the municipality in which the impoundment is constructed should coordinate with upstream municipalities to ensure comprehensive watershed control;
      5. The project otherwise complies with the requirements of this section.
   7. Floodproofing Of Existing Habitable, Residential And Commercial Structures: If construction is required beyond the outside dimensions of the existing building, the outside perimeter of the floodproofing construction shall be placed no farther than ten feet (10') from the outside of the building. Compensation of lost storage and conveyance will not be required for floodproofing activities.
   8. Excavation In The Floodway: When excavation is proposed in the design of bridges and culvert openings, including the modifications to and replacement of existing bridge and culvert structures, or to compensate for lost conveyance for other appropriate uses, transition sections shall be provided for the excavation. The following expansion and contraction ratios shall be used unless an applicant's engineer can prove to IDNR/DWR through engineering calculations or model tests that more abrupt transitions may be used with the same efficiency:
      1. When water is flowing from a narrow section to a wider section, the water should be assumed to expand no faster than at a rate of one foot (1') horizontal for every four feet (4') of the flooded stream's length;
      2. When water is flowing from a wide section to a narrow section, the water should be assumed to contract no faster than at a rate of one foot (1') horizontal for every one foot (1') of the flooded stream's length; and
      3. When expanding or contracting flows in a vertical direction, a minimum of one foot (1') vertical transition for every ten feet (10') of stream length shall be used.
      4. Erosion/scour protection shall be provided inland upstream and downstream of the transition sections.
   9. Seeding And Stabilization Plan: For all activities located in a floodway, a seeding and stabilization plan shall be submitted by the applicant.
   10. Public Flood Control Projects: For public flood control projects, the permitting requirements of this section will be considered met if the applicant can demonstrate to IDNR/DWR through hydraulic and hydrologic calculations that the proposed project will not singularly or cumulatively result in increased flood heights outside the project right of way or easements for all flood events up to and including the 100-year frequency event.
   11. General Criteria For Analysis Of Flood Elevations:
       1. The flood profiles, flows and floodway data in the designated floodway study, referenced in section 12-14-6 of this chapter, must be used for analysis of the base conditions. If the study data appears to be in error or conditions have changed, IDNR/DWR shall be contacted for approval and concurrence on the appropriate base conditions data to use.
       2. If the 100-year designated floodway elevation at the site of the proposed construction is affected by backwater from a downstream receiving stream with a larger drainage area, the proposed construction shall be shown to meet the requirements of this section for the 100-year frequency flood elevations of the designated floodway conditions and conditions with the receiving stream at normal water elevations.
       3. If the applicant learns from IDNR/DWR, local governments, or a private owner that a downstream restrictive bridge or culvert is scheduled to be removed, reconstructed, modified, or a regional flood control project is scheduled to be built, removed, constructed or modified within the next five (5) 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.
   12. Conditional Letter Of Map Revision: If the appropriate use would result in a change in the regulatory floodway location or the 100-year frequency flood elevation, the applicant shall submit to IDNR/DWR and to FEMA all the information, calculations and documents necessary to be issued a conditional designated floodway map revision and receive from IDNR/DWR a conditional approval of the regulatory floodway change before a permit is issued. However, the final designated floodway map will not be changed by IDNR/DWR until as built plans or record drawings are submitted and accepted by FEMA and IDNR/DWR. In the case of nongovernment projects, the municipality in unincorporated areas shall concur with the proposed conditional designated floodway map revision before IDNR/DWR approval can be given. No filling, grading, dredging or excavating shall take place until a conditional approval is issued. No further development activities shall take place until a final letter of map revision (LOMR) is issued by FEMA and IDNR/DWR.
   13. Professional Engineer's Supervision: All engineering analyses shall be performed by or under the supervision of a registered professional engineer.
   14. Construction Activities In Floodway: For all activities in the floodway involving construction within twenty five feet (25') of the channel, the following criteria shall be met:
       1. A natural vegetation buffer strip shall be preserved within at least twenty five feet (25') of the ordinary high water mark of the channel.
       2. Where it is impossible to protect this buffer strip during the construction of an appropriate use, a vegetated buffer strip shall be established upon completion of construction.
       3. The use of native riparian vegetation is preferred in the buffer strip. Access through this buffer strip shall be provided, when necessary, for stream maintenance purposes.
       4. After receipt of conditional approval of the designated floodway change and issuance of a permit and a conditional letter of map revision, construction as necessary to change the designated floodway designation may proceed but no buildings or structures or other construction that is not an appropriate use may be placed in that area until the regulatory floodway designated floodway map is changed and a final letter of map revision is received. The regulatory floodway designated floodway map will be revised upon acceptance and concurrence by IDNR/DWR and FEMA of the "as built" plans.
6. State Review: For those projects listed in this subsection, located in a designated floodway, the following criteria shall be submitted to IDNR/DWR for their review and concurrence prior to the issuance of a permit:
   1. IDNR/DWR will review an engineer's analysis of the flood profile due to a proposed bridge pursuant to subsection E4 of this section.
   2. IDNR/DWR will review an engineer's determination that an existing bridge or culvert crossing is not a source of flood damage and the analysis indicating the proposed flood profile, pursuant to subsection E5 of this section.
   3. IDNR/DWR will review alternative transition sections and hydraulically equivalent storage pursuant to subsections E1, E2 and E8 of this section.
   4. IDNR/DWR will review and approve prior to the start of construction any department projects, dams (as defined in section 12-14-3 of this chapter) and all other state, federal or local units of government projects, including projects of the municipality or county.
7. Other Permits: In addition to the other requirements of this chapter, a development permit for a site located in a floodway shall not be issued unless the applicant first obtains a permit or written documentation that a permit is not required from IDNR/DWR, issued pursuant to 615 Illinois Compiled Statutes 5/5 et seq. No permit from IDNR/DWR shall be required if the division has delegated this responsibility to the Village.
8. Dam Safety Permits: Any work involving the construction, modification or removal of a "dam" as defined in section 12-14-3 of this chapter per 92 Illinois administrative code 702 (rules for construction of dams) shall obtain an Illinois division of water resources dam safety permit prior to the start of construction of a dam. If the Village engineer finds a dam that does not have an IDNR/DWR permit, the Village engineer shall immediately notify the dam safety section of the division of water resources. If the Village engineer finds a dam which is believed to be in unsafe condition, the Village engineer shall immediately notify the owner of the dam, IDNR/DWR, dam safety section in Springfield and the Illinois emergency services and disaster agency (ESDA).
9. Activities That Do Not Require A Registered Professional Engineer's Review: The following activities may be permitted without a registered professional engineer's review. Such activities shall still meet the other requirements of this chapter, including the mitigation requirements.
   1. Underground and overhead utilities that:
      1. Do not result in any increase in existing ground elevations, or
      2. Do not require the placement of aboveground structures in the designated floodway, or
      3. In the case of underground stream crossings, the top of the pipe or encasement is buried a minimum of three feet (3') below the existing streambed, and
      4. In the case of overhead utilities, no supporting towers are placed in the watercourse and are designed in such a fashion as not to catch debris.
   2. Storm and sanitary sewer outfalls that:
      1. Do not extend riverward of the existing adjacent natural bank slope, and
      2. Do not result in an increase in ground elevation, and
      3. Are designed so as not to cause stream erosion at the outfall location.
   3. Construction of sidewalks, athletic fields (excluding fences), properly anchored playground equipment and patios at grade.
   4. Construction of shoreline and stream bank protection that:
      1. Does not exceed one thousand feet (1,000') in length.
      2. Materials are not placed higher than the existing top of bank.
      3. Materials are placed so as not to reduce the cross sectional area of the stream channel or bank of the lake.
   5. Temporary stream crossings in which:
      1. The approach roads will be one-half foot (1/2') or less above natural grade.
      2. The crossing will allow stream flow to pass without backing up the water above the stream bank vegetation line or above any drainage tile or outfall invert.
      3. The top of the roadway fill in the channel will be at least two feet (2') below the top of the lowest bank. Any fill in the channel shall be nonerosive material, such as riprap or gravel.
      4. All disturbed stream banks will be seeded or otherwise stabilized as soon as possible upon installation and again upon removal of construction.
      5. The access road and temporary crossings will be removed within one year after authorization. (Ord. 08-28, 8-11-2008)
         

1. Health Standards: Public health standards.
2. Storage: No developments in the SFHA shall include locating or storing chemicals, explosives, buoyant materials, animal wastes, fertilizers, flammable liquids, pollutants, or other hazards or toxic materials below the FPE.
3. Water, Sewer Systems: New and replacement water supply systems, wells, sanitary sewer lines and on site waste disposal systems may be permitted providing all manholes or other aboveground openings located below the FPE are watertight.
4. Carrying Capacity And Notification: For all projects involving channel modification, fill, or stream maintenance (including levees), the flood carrying capacity of the watercourse shall be maintained. In addition, the Village shall notify adjacent communities in writing thirty (30) days prior to the issuance of a permit for the alteration or relocation of the watercourse.
5. Protecting Buildings: All buildings located within a 100-year floodplain, also known as SFHA, shall be protected from flood damage below the flood protection elevation. However, existing buildings located within a designated floodway shall also meet the more restrictive appropriate use standards included in section 12-14-8 of this chapter. This building protection criteria applies to the following situations:
   1. Construction or placement of a new building;
   2. Nonconforming structures may remain in use, but shall not be enlarged, replaced or structurally altered. A nonconforming structure damaged by flood, fire, wind or other manmade or natural disaster may be restored unless the damage exceeds fifty percent (50%) of its market value. In which case, it must, thereafter, conform to this chapter;
   3. Installing a manufactured home on a new site or a new manufactured home on an existing site. This building protection requirement does not apply to returning a mobile home to the same site it lawfully occupied before it was removed to avoid flood damage; and
   4. Installing a travel trailer on a site for more than one hundred eighty (180) days.
6. Building Protection Requirements: A residential or nonresidential building, when allowed, may be constructed on permanent landfill in accordance with the following:
   1. The lowest floor (including basement) shall be so sited on fill or be otherwise designed and constructed so as to include a freeboard of at least one foot (1') between the lowest floor and the base flood elevation.
   2. The fill shall be placed in layers no greater than one foot (1') deep before compaction and should extend at least ten feet (10') beyond the foundation of the building before sloping below the flood protection elevation. The top of the fill shall be above the flood protection elevation. However, the ten foot (10') minimum may be waived if a structural engineer certifies an alternative method to protect the building from damages due to hydrostatic pressures. The fill shall be protected against erosion and scour. The fill shall not adversely affect the flow or surface drainage from or onto neighboring properties.
7. Elevation: A residential or nonresidential building may be elevated in accordance with the following:
   1. The building or improvements shall be elevated on crawl space, stilts, piles, walls, or other foundation that is permanently open to floodwaters 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 (1') above grade, and consists of a minimum of two (2) openings. The openings must have a total net area of not less than one square inch for every one square foot of enclosed area subject to flooding below the base flood elevation.
   2. 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.
   3. All areas below the flood protection elevation shall be constructed of materials resistant to flood damage. The lowest floor (including basement) and all electrical, heating, ventilating, plumbing, and air conditioning equipment and utility meters shall be located at or above the flood protection elevation. Water and sewer pipes, electrical and telephone lines, submersible pumps, and other waterproofed service facilities may be located below the flood protection elevation.
   4. No area below the flood protection elevation shall be used for storage of items or materials.
   5. When the building wall encloses open space that is below the base flood elevation, gravity storm and sanitary sewer connections are specifically prohibited and overhead sewers are required for the sanitary connections and sumps for the storm sewer connections.
   6. Manufactured homes and travel trailers to be installed on a site for more than one hundred eighty (180) days shall be elevated to or above the flood protection elevation; and, shall be anchored to resist flotation, collapse, or lateral movement by being tied down in accordance with the rules and regulations for the Illinois mobile home tie down act issued pursuant to 77 Illinois administrative code 870.
8. Floodproofing: Only a nonresidential building may be structurally floodproofed (in lieu of elevation) provided that a registered professional engineer shall certify that the building has been structurally dry floodproofed below the flood protection elevation, the structure and attendant utility facilities are watertight and capable of resisting the effects of the base flood or 100-year frequency flood. The building design shall take into account flood velocities, duration, rate of rise, hydrostatic and hydrodynamic forces, the effects of buoyancy, and impacts from debris or ice. Floodproofing measures shall be operable without human intervention and without an outside source of electricity (levees, berms, floodwalls and similar works are not considered floodproofing for the purpose of this subsection).
9. Nonconforming Structures: Nonconforming structures located in a designated floodway may remain in use, but may not be enlarged, replaced or structurally altered. A nonconforming structure damaged by flood, fire, wind or other natural or manmade disaster may be restored unless the damage exceeds fifty percent (50%) of its market value before it was damaged, in which case it shall conform to this chapter. (Ord. 08-28, 8-11-2008)
   

1. New subdivisions, manufactured home parks, annexation agreements, and planned unit developments (PUDs) within the SFHA shall be reviewed to assure that the proposed developments are consistent with sections 12-14-7, 12-14-8, and 12-14-9 of this chapter and the need to minimize flood damage. Plats or plans for new subdivisions, mobile home parks and planned unit developments (PUDs) shall include a signed statement by a registered professional engineer that the plat or plans account for changes in the drainage of surface waters in accordance with the plat act ³.
2. Proposals for new subdivisions, manufactured home parks, travel trailer parks, planned unit developments (PUDs) and additions to manufactured home parks and additions to subdivisions shall include base flood or 100-year frequency flood elevation data and floodway delineations.
3. Streets, blocks, lots, parks and other public grounds shall be located and laid out in such a manner as to preserve and utilize natural streams and channels. Wherever possible, the floodplains shall be included within parks or other public grounds.
4. The plan commission and the board of trustees shall not approve any planned unit development (PUD) or plat of subdivision located outside the corporate limits unless such agreement or plat is in accordance with the provisions of this chapter. (Ord. 08-28, 8-11-2008)
   

³ 765 ILCS 205/2

1. To fulfill those duties, the building commissioner first should use the criteria listed in section 12-14-6, "Base Flood Elevation", of this chapter, to determine whether the development site is located within a floodplain. Once it has been determined that a site is located within a floodplain, the Village engineer must determine whether the development site is within a flood fringe, a designated floodway, or within an SFHA or floodplain on which no floodway has been identified. If the site is within a flood fringe, the Village engineer shall ensure that the minimum requirements of section 12-14-7 of this chapter are met. If the site is within the floodway, the Village engineer shall ensure that the minimum requirements of section 12-14-8 of this chapter are met.
   
   In addition, the general requirements of section 12-14-9 of this chapter shall be met for all developments meeting the requirements of sections 12-14-7 and 12-14-8 of this chapter. The building commissioner shall assure that all subdivision proposals shall meet the requirements of section 12-14-9 of this chapter.
   
   If a variance is to be granted for a proposal, the building commissioner and the Village engineer shall review the requirements of section 12-14-5 of this chapter to make sure they are met. In addition, the building commissioner shall complete all notification requirements.
   
   In order to assure that property owners obtain permits as required in this chapter, the building commissioner may take any and all actions as outlined in section 12-14-16 of this chapter.
2. The building commissioner shall be responsible for the general administration and enforcement of this chapter which shall include the following:
   1. Determining The Floodplain Designation: Check all new development sites to determine whether they are in a special flood hazard area (SFHA). If they are in an SFHA, the Village engineer shall determine whether they are in a floodway or in a flood fringe.
   2. Professional Engineer Review: If the development site is within a floodway the permit shall be referred to a professional engineer (PE) under the employ or contract of the Village for review to ensure that the development meets the requirement of section 12-14-8 of this chapter. In the case of an appropriate use, the PE shall state in writing that the development meets the requirements of section 12-14-8 of this chapter.
   3. Dam Safety Requirements: Ensure that an IDNR/DWR dam safety permit has been issued or a letter indicating no dam safety permit is required, if the proposed development activity includes construction of a "dam" as defined in section 12-14-3 of this chapter. Regulated dams may include weirs, restrictive culverts or impoundment structures.
   4. Other Permit Requirements: Ensure that any and all required federal, state and local permits are received prior to the issuance of a floodplain development permit.
   5. Plan Review And Permit Issuance: Ensure that all development activities within the SFHAs of the jurisdiction of the Village meet the requirements of this chapter and issue a floodplain development permit in accordance with the provisions of this chapter and other regulations of this community when the development meets the conditions of this chapter.
   6. Inspection Review: The Village engineer shall inspect all development projects before, during and after construction to assure proper elevation of the structure and to ensure they comply with the provisions of this chapter.
   7. Elevation And Floodproofing Certificates: Maintain in the permit files an elevation certificate certifying the elevation of the lowest floor (including basement) of a residential or nonresidential building or the elevation to which a nonresidential building has been floodproofed, using a floodproofing certificate, for all buildings subject to section 12-14-9 of this chapter for public inspection and provide copies of same.
   8. Records Of Public Inspection: Maintain for public inspection and furnish upon request base flood data, SHFA and designated floodway maps, copies of federal or state permit documents, variance documentation, conditional letter of map revision, letter of map revision, letter of map amendment and "as built" elevation and floodproofing or elevation and floodproofing certificates for all buildings constructed subject to this chapter.
   9. State Permits: Ensure that construction authorization has been granted by the Illinois division of water resources, for all development projects subject to section 12-14-8 of this chapter, unless enforcement responsibility has been delegated to the Village. Upon acceptance of this chapter by IDNR/DWR and FEMA, responsibility is hereby delegated to the Village as per 92 Illinois administrative code 708 for construction in the regulatory floodway and floodplain when floodways have not been defined in sections 12-14-8 and 12-14-9 of this chapter. However, the following review approvals are not delegated to the Village and shall require review or permits from IDNR/DWR:
      1. Organizations which are exempt from this chapter, as per the Illinois Compiled Statutes;
      2. Department of transportation projects, dams or impoundment structures as defined in section 12-14-3 of this chapter and all other state, federal or local unit of government projects, including projects of the Village and county, except for those projects meeting the requirements of subsection 12-14-8I of this chapter;
      3. An engineer's determination that an existing bridge or culvert crossing is not a source of flood damage and the analysis indicating the proposed flood profile, per subsection 12-14-8E3 of this chapter;
      4. An engineer's analysis of the flood profile due to subsection 12-14-8E4 of this chapter;
      5. Alternative transition sections and hydraulically equivalent compensatory storage as indicated in subsections 12-14-8E1, E2 and E8 of this chapter;
      6. Permit issuance of structures within or over publicly navigable rivers, lakes and streams;
      7. Any changes in the base flood elevation or floodway locations; and
      8. Base flood elevation determinations where none now exist.
   10. Cooperation With Other Agencies: Cooperate with state and federal floodplain management agencies to improve base flood or 100-year frequency flood and designated floodway data and to improve the administration of this chapter. Submit data to IDNR/DWR and the federal emergency management agency for proposed revisions of a regulatory map. Submit reports as required for the national flood insurance program. Notify the federal emergency management agency of any proposed amendments to this chapter.
   11. Promulgate Regulations: Promulgate rules and regulations as necessary to administer and enforce the provisions of this chapter, subject however to the review and approval of IDNR/DWR and FEMA for any chapter changes. (Ord. 08-28, 8-11-2008)
       

1. If such owner fails after ten (10) days' notice to correct the violation:
   1. The Village may make application to the circuit court for an injunction requiring conformance with this chapter or make such other order as the court deems necessary to secure compliance with this chapter.
   2. Any person who violates this chapter shall, upon conviction thereof, be fined in accordance with title 1, chapter 4 of this code for each offense.
   3. A separate offense shall be deemed committed upon each day during or on which a violation occurs or continues.
   4. The Village may record a notice of violation on the title to the property.
2. The building commissioner shall inform the owner that any such violation is considered a wilful act to increase flood damages and, therefore, may cause coverage by a standard flood insurance policy to be suspended.
3. Nothing herein shall prevent the Village from taking such other lawful action to prevent or remedy any violations. All costs connected therewith shall accrue to the person or persons responsible. (Ord. 09-16, 10-12-2009)