Loading...
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illage of Deerfield Code, as hereby adopted affect any suit or or any rights acquired, or causes of actions accrued or repealed hereby, nor shall be lost, impaired or ORDINANCE NO. 0 -92 -38 AN ORDINANCE PROVIDING FOR THE ADOPTION OF THE VILLAGE OF DEERFIELD STORMWATER MANAGEMENT CODE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 Stormwater Management Code 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 -2- Stormwater Management Code 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. -3- 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 Stormwater Management Code 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 -4- Stormwater Management Code 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 -5- Stormwater Management Code 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 Stormwater Management Code 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. -7- Stormwater Management Code 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 ZZ Stormwater Management Code 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 cm Stormwater Management Code 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 -10- Stormwater Management Code 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 -11- Stormwater Management Code 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 -12- Stormwater Management Code 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 -13- Stormwater Management Code Village of Deerfield 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 -14- Stormwater Management Code 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 -15- Stormwater Management Code 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. -16- Stormwater Management Code 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. -17- Stormwater Management Code Village of Deerfield (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. -18- Stormwater Management Code Village of Deerfield (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 -19- Stormwater Management Code Village of Deerfield 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. -20- Stormwater Management Code Village of Deerfield (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. -21- Stormwater Management Code Village of Deerfield (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 -22- Stormwater Management Code Village of Deerfield 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 -23- Stormwater Management Code Village of Deerfield 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 -24- Stormwater Management Code Village of Deerfield (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 -25- Stormwater Management Code Village of Deerfield 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. -26- Stormwater Management Code Village of Deerfield (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 -27- Stormwater Management Code Village of Deerfield 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 := Stormwater Management Code 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 -29- Stormwater Management Code Village of Deerfield 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. -30- Stormwater Management Code Village of Deerfield 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; -31- Stormwater Management Code Village of Deerfield (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 -32- Stormwater Management Code Village of Deerfield 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 -33- Stormwater Management Code Village of Deerfield 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. -34- Stormwater Management Code Village of Deerfield (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 -35- Stormwater Management Code Village of Deerfield 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, -36- Stormwater Management Code Village of Deerfield 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 -37- Stormwater Management Code Village of Deerfield 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. -38- Stormwater Management Code Village of Deerfield 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. -39- Stormwater Management Code Village of Deerfield (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 -40- Stormwater Management Code Village of Deerfield 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. -41- Stormwater Management Code Village of Deerfield (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. -42- Stormwater Management Code Village of Deerfield (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. -43- Stormwater Management Code Village of Deerfield (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: -44- Stormwater Management Code Village of Deerfield (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. -45- Stormwater Management Code Village of Deerfield (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 -46- Stormwater Management Code Village of Deerfield 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 -47- Stormwater Management Code Village of Deerfield 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 -48- Stormwater Management Code Village of Deerfield 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 -49- Stormwater Management Code Village of Deerfield 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: -50- Stormwater Management Code Village of Deerfield 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 -51- Stormwater Management Code Village of Deerfield 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. -52- Stormwater Management Code Village of Deerfield -53- Stormwater Management Code Village of Deerfield 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. -54- Stormwater Management Code Village of Deerfield 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. -55- Stormwater Management Code Village of Deerfield 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. -56- 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. -57- 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. -58- 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. -59- 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. -61- 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. -62- 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. -63- 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)