§ 164.065 RIVERINE FLOODPLAIN.

   (A)   These standards apply to riverine regulatory floodplains without a regulatory floodway.

   (B)   The applicant shall obtain approval from IDNR/OWR for all development any portion of which is located partially or completely within the regulatory floodplain (without a delineated regulatory floodway) with a tributary drainage area of 640 acres or more.

      (1)   The development shall not singularly or cumulatively result in an obstruction of flood flows or potential flood damages outside the site due to an increase in flood heights, velocities or loss of floodplain area storage.

      (2)   A professional engineer shall submit a study that demonstrates one of the following:

         (a)   Determine a floodway which meets the definition of a regulatory floodway and demonstrate that the proposed development meets the floodway standards in § 164.064; or

         (b)   Determine a BFE and demonstrate that the proposed development will maintain the existing conditions conveyance, will not increase flood velocities, will not increase flood profiles and will compensate for any lost floodplain storage.

(Ord. 10-164, passed 6-17-2010)

§ 164.066 BRIDGE AND CULVERT STANDARDS.

   These standards are for the reconstruction, modification or new construction of bridges, culvert crossings and roadway approaches located in the regulatory floodplain.

   (A)   A proposed new structure shall not result in an increase of upstream flood stages greater than one- tenth foot when compared to the existing conditions for all flood events up to and including the base flood event unless contained within the channel banks or recorded easements. The evaluation must be submitted to the IDNR-OWR for review and a permit obtained.

   (B)   If the proposed new structure will increase upstream flood stages greater than one-tenth foot, the applicant must contact IDNR/OWR for a dam safety permit or waiver. The Director shall be copied on all related correspondence.

   (C)   Lost regulatory floodplain storage must be replaced as required in § 164.063 except that artificially created storage lost due to a reduction in head loss behind an existing bridge or culvert crossing shall not be required to be replaced, provided no flood damage will be incurred downstream.

   (D)   Velocity increases must be mitigated by use of appropriate measures to avoid scour, erosion and sedimentation at the structure.

   (E)   For modification or replacement of existing structures, the existing structure must first be evaluated in accordance with IDNR/OWR Rules (17 Ill. Adm. Code Part 3708) to determine if the existing structure is a source of flood damage. If the structure is a source of flood damage, the applicant’s engineer shall submit justification to allow the damage to continue and evaluate the feasibility of relieving the structure’s impact. Modifications or replacement structures shall not increase flood stages (0.0 feet) compared to the existing condition for all flood events up to and including the base flood event. The evaluation must be submitted to IDNR/OWR, for review and concurrence before a permit is issued. The County Executive and the Chief Subdivision Engineer shall be copied on all related correspondence.

   (F)   If any work is proposed in, near or over a public body of water, a permit or letter indicating a permit is not required must be obtained from IDNR/OWR.

   (G)   The hydraulic analysis for the backwater caused by the bridge showing the existing condition and proposed regulatory profile must be submitted to IDNR/OWR for concurrence that a CLOMR is not required.

   (H)   (1)   Construction vehicles shall cross-streams by the means of existing bridges or culverts.

      (2)   Where an existing crossing is not available, a temporary crossing that has been issued a permit or waiver by IDNR/OWR shall be constructed in which:

         (a)   The approach roads will be one- half foot or less above existing grade;

         (b)   The crossing will allow stream flow to pass without backing up the water above the stream bank vegetation line or above any drainage tile or outfall;

         (c)   The top of the roadway fill in the channel will be at least two feet below the top of the lowest bank. Any fill in the channel shall be non-erosive material, such as riprap or gravel; and

         (d)   The access road and temporary crossings will be removed within one year after installation, unless an extension of time is granted by the Chief Subdivision Engineer.

(Ord. 10-164, passed 6-17-2010)

§ 164.067 WETLAND, WATERS AND BUFFER STANDARDS.

   (A)   Generally. Waters of the United States is a defined term (§ 164.004) in this chapter and refers to areas that are under the jurisdictional authority and regulated by the United States Army Corps of Engineers. Isolated waters of the county are under the jurisdictional authority of this chapter and is a defined term in § 164.004.

   (B)   Applicability.

      (1)   Development activities that create an impact within a wetland, waters of the United States, isolated waters of the county, or their associated buffers, regardless of the Corps of Engineers jurisdiction, must submit a site development permit application to the County Land Use Department.

      (2)   The applicant shall submit a jurisdictional determination for the United States Army Corps to determine the proper permitting agency.

      (3)   No site development permit for activities that may impact wetlands, waters or their associated buffers shall be issued unless the County Land Use Department finds that:

         (a)   The development will not detrimentally affect or destroy, without mitigation (see § 164.082), wetlands, waters or their associated buffer areas, nor impair their natural functions, with the exception of impacts to individual wetlands/waters covering one-tenth acre or less total area, which may be impacted without mitigation required;

         (b)   The location of natural features and the site’s topography have been considered in the designing and siting of all physical improvements, and it has been determined that impacts to wetlands, waters, and buffers cannot be avoided; and

         (c)   Adequate assurances have been received that the clearing of the site of topsoil, trees and other natural features will not occur before the commencement of building operations; only those areas approved for the placement of physical improvements may be cleared.

      (4)   The following existing developments are generally considered to be exempt from wetland provisions of this chapter. However, the Chief Subdivision Engineer reserves the right on a case-by- case basis to determine that a particular waterbody within these categories of waters is a regulated isolated waters of the county:

         (a)   Waste treatment systems, including treatment ponds or lagoons designed to meet the requirements of the Clean Water Act (other than cooling ponds as defined in 40 C.F.R. § 123.11(m) which also meet the criteria of this definition);

         (b)   Drainage and irrigation ditches excavated on dry land;

         (c)   Artificially irrigated areas that would revert to upland if the irrigation ceased;

         (d)   Artificial lakes created by excavating and/or berming dry land to collect and retain water and which are used exclusively for the purposes as stormwater storage, stock watering, irrigation or settling basins;

         (e)   Artificial reflecting or swimming pools or other small ornamental bodies of water created by excavating and/or berming dry land to retain water for primarily aesthetic reasons; or

         (f)   Waterfilled depressions created in dry land incidental to construction activity and pits excavated in dry land for the purpose of obtaining fill, sand or gravel unless and until the construction or excavation operation is abandoned and the resulting body of water meets the definition of waters.

      (5)   There shall be no development, including clearing or removal of natural ground cover and/or trees, within isolated waters of the county or waters of the United States for any purpose, unless a permit is granted subject to the provisions of this chapter.

      (6)   This chapter is not intended to preclude the removal of vegetation (e.g., removal of exotic species or selective thinning in order to increase sunlight penetration) as part of a management program for maintenance and restoration of natural areas.

      (7)   The County Land Use Department may limit development activity in or near a wetland, water’s or buffer to specific months, and to a maximum number of continuous days or hours, in order to minimize adverse impacts. Also, the County Land Use Department may require that equipment be operated from only one side of a stream, lake or pond in order to minimize bank disruption. Other development techniques, conditions and restrictions may be required in order to minimize adverse impacts on any related areas not subject to development activity.

   (C)   Requirements for wetland delineation. A wetland delineation report shall be submitted along with a site development permit application for any activities that may impact wetlands, waters of the United States, waters of the county or their associated buffers.

      (1)   The applicant shall identify the boundaries, extent, function and quality of all wetland areas on the development site and prepare a wetland determination report. The presence and extent of wetland areas shall be determined by, or under supervision of, a qualified wetland professional using an on-site wetland procedure within three years of the initial permit application date in accordance with the methodology contained in the 1987 Corps of Engineers Wetland Delineation Manual or as otherwise noted below.

      (2)   The following are minimum requirements for the wetland determination report:

         (a)   A plan showing the exact location of wetlands within the development boundaries. The wetland boundary shall be flagged in the field and surveyed, and the boundary of the wetland plotted on a plat of survey;

         (b)   An aerial photograph delineating the wetland and the development boundary;

         (c)   A copy of the following maps (most recent) delineating the development boundary:

            1.   U.S.G.S. quadrangle map;

            2.   NRCS (Natural Resources Conservation Service) wetland map;

            3.   National wetland inventory map;

            4.   FEMA floodplain map;

            5.   County soil survey; and

            6.   Hydrologic atlas.

         (d)   United States Army Corps of Engineers data sheets with representative color photographs provided for each data point;

         (e)   A written description of the wetland(s), the delineation report, including farmed wetland determinations, prepared in conformance with current Corps of Engineers requirements or Food Security Act provisions, and the following growing season and boundary confirmation requirements:

            1. The growing season for the purposes of a final wetland delineation that will be made part of an application package will generally be between April 15 and October 31 each year, provided the ground is neither frozen to the point that soil probes or pits cannot be completed or there is any snow cover present. If the weather has been unusually warm or cold at the beginning or end of the growing season, the Chief Subdivision Engineer may shorten or lengthen these periods based on his or her discretion;

            2.   The approximate location, extent, and relative quality of off-site wetlands on properties adjoining the development shall be identified by using the first of the following documents or procedures pertaining at the time of development:

               a.   Site-specific delineation according to the 1987 Federal Wetland Delineation Manual;

               b.   If a site-specific delineation is not available, use most current NRCS wetland maps; and

               c.   National Wetland Inventory (NWI) map.

            3.   A floristic quality assessment along with a statement regarding whether or not the site contains high quality aquatic resources (HQAR);

            4.   Documentation that the development is in compliance with the State Department of Natural Resources Endangered Species Consultation Program and the State Natural Areas Preservation Act;

            5.   Documentation that the development is in compliance with the United States Fish and Wildlife Service’s consultation program under the Endangered Species Act; and

            6.   Wetland/waters delineation plan view drawing that includes the proposed site development plan, with the existing conditions and topography overlain with the following:

               a.   All onsite wetland and waters areas;

               b.   All required buffer areas;

               c.   All proposed wetland, waters, and buffer impact areas;

               d.   If applicable, identification of where buffer averaging is proposed, including calculation of the impact and replacement area; and

               e.   A table listing the acreages of all wetlands, waters, buffers and buffer averaged areas.

   (D)   Requirements for buffer areas. Buffer areas shall be required for all areas defined as either waters of the United States or isolated waters of the county. Buffer areas are divided into two types, linear buffers and water body buffers. Buffers required by Army Corps of Engineers for wetland impacts under their jurisdiction will be considered as compliant with this section’s requirements.

      (1)   Linear buffers shall be designated along both sides of all channels meeting the definition of waters of the United States or isolated waters of the county. The buffer width shall be determined as follows.

         (a)   When the channel has a watershed less than one square mile, the minimum buffer shall be 50 feet on each side of the channel.

         (b)   When the channel has a watershed greater than one square mile, the minimum buffer shall be 75 feet on each side of the channel.

         (c)   Linear HQAR and streams shall have a minimum buffer width of 100 feet an each side of the channel.

      (2)   Water body buffers shall encompass all non-linear bodies of water meeting the definition of either waters of the United States or isolated waters of the County. The buffers width shall be determined as follows.

         (a)   For all water bodies or wetlands with a total surface area greater than one-tenth acre but less than one acre, a minimum buffer width of 30 feet shall be established.

         (b)   For all water bodies or wetlands with a total surface area greater than one acre but less than two and one-half acres, a minimum buffer width of 40 feet shall be established.

         (c)   For all water bodies or wetlands with a total surface area greater than two and one-half acres, a minimum buffer width of 50 feet shall be established.

         (d)   Non-linear HQAR shall have a minimum buffer width of 100 feet.

      (3)   In areas where state or federal threatened and endangered species are present or for a state natural area inventory site, buffer widths may be modified upon approval of the Chief Subdivision Engineer. Any modification requires approval by the Chief Subdivision Engineer following consultation with the State Department of Natural Resources or United States Fish and Wildlife Service.

      (4)   Buffer areas for water bodies meeting the definition of waters of the United States or isolated waters of the county shall extend from the ordinary high water mark. Buffer areas for wetlands shall extend from the edge of the delineated wetland. A property may contain a buffer area that originates from waters of the United States or isolated waters of the county on another property. On-site verification of the off-site wetland or waters limit is preferred. When an on-site determination is not possible, the limit should be determined through review and annotation of aerial photo mapping which must be provided with the wetland delineation report or permit application package.

      (5)   Features of the stormwater management system approved by the county may be within the outer 50% of the buffer area of the development.

      (6)   Access through buffer areas shall be provided, when necessary, for maintenance purposes.

      (7)   All existing roadside ditches, improvement to existing public road and trail developments or alignments, and utility projects that are located in a public right-of-way are exempt from buffer requirements.

      (8)   Stormwater discharges that enter a buffer shall have appropriate energy dissipation measures to prevent erosion and scour.

      (9)   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)   Trails and bike/pedestrian paths may encroach provided: they are no wider than 12 feet; no closer than ten feet from the edge of the wetland; and runoff from these facilities is unconcentrated flow.

         (b)   Utility installation or maintenance, construction of stormwater facilities and maintenance of stormwater facilities shall be allowed.

         (c)   Boat docks, boathouses and piers shall be allowed and the provisions of division (D)(1) above shall apply.

      (10)   Buffer areas disturbed by construction or as part of a revegetation plan shall be revegetated using Native Plant Guide for Streams and Stormwater Facilities in Northeastern Illinois, NRCS, et al., (as amended) as a minimum standard. Performance standards for the required revegetation will at a minimum require at least one year of monitoring with at least 90% cover for non-aquatic vegetative zones within one year of planting.

      (11)   Buffer averaging. If a Corps of Engineers buffer is not required, the buffer width for a development site may be decreased to a minimum of one-half of the buffer width required, upon approval of the Chief Subdivision Engineer, provided that the new buffer limit is delineated by a path, fence or permanent signage and that the lost buffer area is made up elsewhere along the same wetland perimeter. The consultation process of IDNR or United States Fish and Wildlife Service may override the ability to average buffer areas.

      (12)   Preservation of buffer areas shall be provided by deed or plat restrictions.

   (E)   Buffer area permitted activities.

      (1)   Minor improvements such as walkways, benches, comfort stations, informational displays, directional signs, footbridges, observation decks and docks;

      (2)   Walkways and observation decks may encroach provided that they are no wider than 12 feet and that the runoff from the surfaces enters the buffer area as unconcentrated flow. These items shall avoid high quality wetland areas, and shall not adversely affect natural areas designated in the state natural areas inventory or the habitat of rare or endangered species;

      (3)   Only limited filling and excavating necessary for the development of public boat launching ramps, swimming beaches or the development of park shelters or similar structures is allowed. The development and maintenance of roads, parking lots and other impervious surfaces necessary for permitted uses are allowed only on a very limited basis, and where no alternate location outside of the setback area is available;

      (4)   The maintenance, repair, replacement and reconstruction of existing structures;

      (5)   The establishment and development of public and private parks and recreation areas, outdoor education areas, historic natural and scientific areas, game refuges, fish and wildlife improvement projects, game bird and animal farms, wildlife preserves and public boat launching ramps;

      (6)   A buffer area may be used for passive recreation (e.g., bird watching, walking, jogging, bicycling, horseback riding and picnicking) and it may contain pedestrian, bicycle or equestrian trails provided that impervious surfaces are no wider than 12 feet and that the runoff from these areas enters the buffer area as unconcentrated flow;

      (7)   Utility maintenance and maintenance of stormwater facilities shall be allowed; and

      (8)   Boat docks, boathouses and piers shall be allowed and the provisions of division (D)(3) above shall apply.

   (F)   Mitigation. Mitigation is required for all impacts to wetlands greater than one-tenth acre of isolated waters of the county that are high quality aquatic resources (HQAR). Mitigation is required for all impacts to wetlands that are greater than one-fourth acre of isolated waters of the county that are not high-quality aquatic resources. Mitigation required by Army Corps of Engineers for wetland impacts under their jurisdiction will be considered as compliant with this section’s requirements. Requirements for mitigation are as follows.

      (1)   All mitigation shall occur in the county. Mitigation shall use the following hierarchy; with on-site mitigation preferred. Allowance to the next lower step is permitted only when justified through sequencing specified or when the higher step is not available:

         (a)   On-site wetland mitigation meeting the requirements of this chapter;

         (b)   In the same watershed as wetland impact in a county-approved wetland mitigation bank;

         (c)   County Forest Preserve District Wetland Restoration Funds. This mitigation option may only be used for wetland impacts where there are no available mitigation credits within the county; and

         (d)   A United States Army Corps of Engineers approved wetland mitigation bank.

      (2)   Mitigation shall provide for the replacement of the lost wetland environment at the following ratios (creation acreage to wetland impact acreage):

         (a)   A minimum of 1.5:1 for impacts to non-HQAR wetlands;

         (b)   A minimum of 3:1 for impacts to HQAR wetlands;

         (c)   A minimum of 6:1 for impacts to forested or fen HQAR wetlands; and

         (d)   A minimum of 1:1 for impacts to open waters that are not HQAR

      (3)   Mitigated isolated waters of the county shall be designed to duplicate or improve the hydrologic and biologic features of the original wetland impact area.

      (4)   The mitigation plan shall include the proposed grading plan, planting plan and specifications. It shall also include a wetland mitigation management and monitoring plan indicating the legally responsible parties for long-term operation and maintenance and dedicated funding sources.

      (5)   A project mitigation document shall be submitted in conformance with the latest version of the Chicago District Corps of Engineers Mitigation Guidelines and Requirements.

      (6)   Creation of wetlands for the mitigation of wetland impacts shall not take place within detention facilities.

      (7)   A five-year period of management, maintenance and monitoring program will be required. The proposed management, maintenance and monitoring plan text should generally follow the standards of the Chicago District Corps of Engineers.

      (8)   A five-year wetland monitoring and maintenance guarantee for 125% of monitoring and maintenance cost estimate shall be submitted prior to obtaining a permit. The guarantee shall be in accordance with §§ 164.180 through 164.183 and shall include costs for construction, monitoring and management activities during the five-year monitoring period.

      (9)   Long-term ownership and funding must be identified. A long-term management plan must be submitted that guides the long-term owner/manager in the proper care of the area. This plan’s operation would commence following the required initial maintenance and monitoring period.

      (10)   On-site mitigation is preferred when the cumulative area of mitigation and preserved wetlands exceeds one and one-half acres.

      (11)   If the proposed mitigation area is less than one and one-half acres it is preferred that wetland mitigation banks be used, unless the developer can provided assurances that the area will be successful and will receive a high level of care in perpetuity.

      (12)   Mitigation areas shall have the same buffer requirements as existing wetlands and waters.

      (13)   The developer shall provide the Chief Subdivision Engineer annual monitoring reports prepared by a qualified wetland professional on the status of the constructed mitigation measures for five years from date of completion of the mitigation project. The developer shall undertake all necessary remedial action to bring the area into compliance with the wetland mitigation plan.

      (14)   Where a proposed development activity is less than one acre in area or the development consists of a single family residence, the Land Use Department, upon approval of the Chief Subdivision Engineer, may simplify the submission requirements of the above division provided that the person responsible for any development shall implement necessary erosion control measures to satisfy the purpose and intent set forth in §§ 164.035 through 164.047 of this chapter.

(Ord. 10-164, passed 6-17-2010)

SITE DEVELOPMENT PERMIT SUBMITTAL REQUIREMENTS

§ 164.080 GENERAL REQUIREMENTS.

   (A)   Site development permit and other permits required.

      (1)   Except as otherwise provided in this chapter, no person shall commence or perform any clearing, grading, stripping, excavating or filling of land without having first obtained a site development permit from the Development Review Division of the County Land Use Department. Failure to obtain a site development permit is a violation of this chapter.

         (a)   A site development permit shall not be required for any one of the following construction activities unless the property is located in a floodplain, if there is regulatory floodplain within the property boundary or if the development impacts a wetland and associated buffer or an existing stormwater drainage system:

            1.   Clearing, grading, stripping, excavation or filling associated with the construction of a single-family residence or an addition to an existing single-family residence on a site equal to or greater than five acres;

            2.   Clearing, grading, stripping, excavating or filling associated with the construction of an addition to an existing residential building or construction of a single-family accessory structure on a site equal to or greater than two and one-half acres provided that the proposed structure is equal to or less than 3,000 square feet in area;

            3.   Clearing, grading, stripping, excavating or filling associated with the construction of an addition to an existing residential building or the construction of a single-family residential accessory structure on a site less than two and one-half acres if the footprint of either is equal to or less than 1,000 square feet in area;

            4.   Clearing, grading, stripping, excavating or filling associated with the agricultural practices, including the implementation of conservation practices included in a farm conservation plan approved by the Will/South Cook Soil and Water Conservation District, and including the construction of structures used for agricultural purposes, provided the construction meets the requirements of § 164.024;

            5.   Clearing, grading, stripping, excavating or filling associated with the installation, renovation or replacement of a septic system to serve an existing dwelling or structure;

            6.   Excavation, fill or any combination thereof which is equal to or less than 100 cubic yards in volume on a site less than two and one-half acres in size when structures are not involved and the proposed construction activity is not within 20 feet of a property line;

            7.   Excavation, fill or any combination thereof which is equal to or less than 200 cubic yards in volume on a site equal to or greater than two and one-half acres when structures are not involved and the proposed construction activity is not within 20 feet of a property line;

            8.   Removal of plant cover equal to or less than 5,000 square feet in an area when structures are not involved;

            9.   Driveways installed at existing grade on residential property that do not impact existing stormwater drainage systems;

            10.   Excavation or removal of vegetation in public utility easements for the purpose of installing or maintaining utilities;

            11.   Excavation or removal of vegetation in a right-of-way for the purpose of installing or maintaining utilities, including storm sewers; or

            12.   Maintenance of an existing stormwater facility, not requiring other state or federal permits or approvals.

         (b)   A site development permit is required for all development that is located in the regulatory floodplain, requires stormwater detention facilities and/or stormwater management system per § 164.020(B), which do not meet the exemptions of § 164.020(C) of this chapter.

         (c)   A site development permit is required for any development that:

            1.   Creates a wetland impact within an area defined as waters of the United States;

            2.   Creates a wetland impact within an area defined as isolated waters of the county; or

            3.   Occurs in buffer areas adjoining waters of the United States or isolated waters of the county.

      (2)   All development shall secure all appropriate stormwater management related approvals, including, without limitation, an IDNR- OWR floodway/floodplain construction permit, a ACOE 404 permit and an IDNR-OWR dam safety permit if required, from all federal, state and regional authorities and other appropriate federal, state, and regional approvals prior to the issuance of a site development permit for areas of a site requiring other approvals.

   (B)   Permit review fees. All permit fees shall be paid at the time of permit issuance. Permit fees are established by the County Board. Fees may include, but are not limited to, the cost of permit administration, review and inspections prior to construction, during construction and within the permanent cover establishment period following construction. Refer to § 158.01 for the fee schedule.

   (C)   Professional seals and certifications required.

      (1)   The design of stormwater facilities, calculations for the determination of the regulatory floodplain, or calculations of the impacts of development shall meet the standards of this chapter and shall be prepared, signed and sealed by a professional engineer registered in the state. The professional engineer shall provide an opinion that the technical submittal meets the criteria required by this chapter or the applicable certified community ordinance.

      (2)   For structures (not including earth embankments) that are subject to a differential water pressure greater than three feet, the submittal shall include evidence that the subject design has been prepared by a qualified professional who shall, as a minimum, have registration with the state as a professional engineer. These reviews shall include stability of the structure under design conditions considering the protection of downstream life and property in the event of a failure. When directed by the Chief Subdivision Engineer the calculations submitted for the structures shall be reviewed, signed and sealed by a registered structural engineer.

      (3)   For projects which include earth embankments which are subjected to a differential water pressure the submittal shall include evidence that the embankment design and construction specifications are adequate for the design conditions. This review shall include consideration of the existing foundation soils for the embankment, the materials from which the embankment is to be constructed, compaction requirements for the embankment and protection of the embankment from failure due to overtopping. Construction and materials specifications for all embankments shall be included with the plan set submittal. When directed by the Chief Subdivision Engineer, or when the impounded water pressure differential exceeds three feet, or when appropriate considering the volume impounded and water surface elevation differential to which the embankment is subjected, these calculations may be required to be reviewed, signed and sealed by a qualified geotechnical or structural engineer.

      (4)   A topographical map of the site, record drawings and other required drawings shall be prepared, signed, and sealed by a professional land surveyor or professional engineer and tied to NAVD 88 and any FEMA benchmarks.

(Ord. 10-164, passed 6-17-2010)

§ 164.081 DURATION AND REVISION TO PERMITS.

   (A)   Permit expiration. Permits expire one year following the date of permit issuance or upon expiration of state or federal permits required for stormwater management.

   (B)   Permit extension. If the permitted activity has been started but is not completed by the expiration date of the permit, and the permittee intends to pursue the permitted activity, then the permittee may submit a written request that the expiration date be extended. Upon receipt of the request, the Chief Subdivision Engineer may extend the expiration date in one-year increments a maximum of three times for permitted activities outside regulatory floodplains and floodways. Expiration dates for permitted activities in regulatory floodplains and floodways may be extended in one-year increments a maximum of three times provided the activity is in compliance with the then current requirements of this chapter.

   (C)   Permit revision. If, after permit issuance, the permittee decides to revise the approved plans, the permittee shall submit revised plans to the Chief Subdivision Engineer along with a written request for approval. If the Chief Subdivision Engineer determines that the revised plans are in compliance with the then current requirements of this chapter or the applicable, an approval of the revised plans may be issued.

(Ord. 10-164, passed 6-17-2010)

§ 164.082 REQUIRED SUBMITTALS.

   (A)   Generally. All permit submittals shall include the material listed in the sections for the applicable type of development, unless the submittal requirements are specifically modified by the procedure in division (B) below.

   (B)   Modification of submittal requirements. The Chief Subdivision Engineer may, at his or her discretion, modify the submittal requirements on a case-by-case basis considering the size, complexity and likelihood that a development will affect the discharge of stormwater. These modifications shall be requested and answered in writing. The Chief Subdivision Engineer’s response shall note the relevant findings, and be specific as to what submittal requirements are changed. The Director shall be copied on all related correspondence. The Chief Subdivision Engineer may not modify submittal requirements for any aspect of the development requiring state or federal permits or approvals, nor for any application in which any variance is requested.

   (C)   Application and project overview. The applicant shall provide the following information as a minimum, on forms or in a format approved by the Chief Subdivision Engineer:

      (1)   The name and legal address of the owner(s) of the site and the permit applicant;

      (2)   The common address, legal description, property identification number (PIN) of the site;

      (3)   The name of the project, area of the site in acres, type of development;

      (4)   A general narrative description of the development, existing and proposed conditions, and project planning principles considered, including best management practices used;

      (5)   Affidavits signed by the owner or the applicant’s authorized representative attesting to their understanding of the requirements of this chapter and their intent to comply therewith;

      (6)   A statement of opinion by a qualified person either denying or acknowledging the presence of floodplain on the development site;

      (7)   Copies of other stormwater related permits or permit applications as required;

      (8)   A subsurface drainage investigation report; and

      (9)   An engineer’s estimate of probable construction cost of the stormwater facilities.

   (D)   Plan set submittal. All applicants for a site development permit shall provide the following basic plan exhibits: site topographic map; general plan view drawing; sediment/erosion control plan; and a vicinity topographic map. Each exhibit may be on more than one drawing for clarity. The development plan and associated stormwater/floodplain calculations shall be submitted on a digital diskette in a format compatible with the county’s geographic information system (GIS). The specific information to be included on each exhibit shall be as noted below.

      (1)   Site topographic map meeting the following requirements shall be submitted:

         (a)   Map scales as one inch equals 50 feet (or less) and accurate to +/- 0.5 feet;

         (b)   Existing and proposed contours (one-foot intervals) on-site and within 100 feet of site;

         (c)   Existing and proposed drainage patterns and watershed boundaries;

         (d)   Delineation of pre-development regulatory floodplain/floodway limits;

         (e)   Delineation of post-development regulatory floodplain/floodway limits;

         (f)   Location of cross-sections and any other hydrologic/hydraulic computer modeled features;

         (g)   Location of all on-site drain tiles;

         (h)   Boundary of all wetlands, lakes, ponds and the like with normal water elevation noted;

         (i)   Location of all existing buildings and those to remain on the site noted;

         (j)   Nearest base flood elevations;

         (k)   FEMA and any site-specific benchmarks (tied to county benchmarks) used; and

         (l)   Highlight all contours used in the calculation of depressional storage.

      (2)   General plan view drawing meeting the following requirements shall be submitted:

         (a)   Drawing at the same scale as the site topographic map;

         (b)   Existing major and minor stormwater systems;

         (c)   Proposed major and minor stormwater systems;

         (d)   Design details for stormwater facilities (i.e., structure and outlet work detail drawings and the like);

         (e)   Scheduled maintenance program for permanent stormwater facilities including BMP measures;

         (f)   Planned maintenance tasks and schedule;

         (g)   Identification of entities responsible for maintenance;

         (h)   Permanent public access maintenance easements granted or dedicated to, and accepted by, a government entity;

         (i)   Proposed regulatory floodplain and floodway location (with the base flood and flood protection elevations noted); and

         (j)   Highlight all plan areas at elevations below the 100-year high water elevation of site runoff storage facilities.

      (3)   Sediment and erosion control plan meeting the following requirements shall be submitted:

         (a)   Drawings at the same scale as the site topographic map;

         (b)   Sediment/erosion control installation measures and schedule;

         (c)   Existing and proposed roadways, structures, parking lots, driveways, sidewalks and other impervious surfaces;

         (d)   Limits of clearing and grading;

         (e)   Floodplain/floodway locations;

         (f)   Proposed buffer location, existing soil types, vegetation and land cover conditions; and

         (g)   List of maintenance tasks and schedule for sediment/erosion control measures.

      (4)   Vicinity topographic map meeting the following requirements shall be submitted:

         (a)   Vicinity topographic map identifying all off-site areas draining to the development and downstream to the receiving intermittent or perennial stream. (A two foot contour map is preferred at a scale readable by the reviewer but a USGS quadrangle map is acceptable);

         (b)   Watershed boundaries for areas draining through or from the development;

         (c)   Soil types related to hydrologic soils group, vegetation and land cover affecting runoff upstream of the site for any area draining through the site;

         (d)   Location of development site within the major watershed(s); and

         (e)   Show the overland flow path from the downstream end of the development to the receiving intermittent or perennial stream.

   (E)   Stormwater submittal. The stormwater submittal shall include narrative discussion and calculations to support a finding that the proposed development complies with the technical requirements of the permitting authorities ordinance. The submittal shall consist of, at a minimum, the following material:

      (1)   A narrative description of the existing and proposed site drainage patterns and conditions. Include description of off-site conditions, which help to identify stormwater issues considered in the design;

      (2)   A schedule for implementation of the site stormwater plan;

      (3)   On-site and off-site runoff calculations which address the following:

         (a)   Documentation of the procedures/assumptions used to calculate hydrologic and hydraulic conditions for sizing major and minor systems;

         (b)   Cross-section data for open channels;

         (c)   Hydraulic grade line and water surface elevations under design flow conditions; and

         (d)   Hydraulic grade line and water surface elevations under base flood flow conditions.

      (4)   Site runoff storage calculations, which address the following:

         (a)   Calculation of hydraulically connected impervious area and corresponding retention volume;

         (b)   Documentation of the procedures/ assumptions used to calculate hydrologic and hydraulic conditions for determining the allowable release rate;

         (c)   Documentation of the procedures/ assumptions used to calculate on-site depressional storage;

         (d)   Documentation of the procedures/ assumptions used to calculate hydrologic and hydraulic conditions for determining the storage volume (on hard copy and on disc);

         (e)   Elevation-area-storage data and calculations for site runoff storage;

         (f)   Elevation-discharge data and calculations specifically related to the outlet control structure depicted in the plan exhibits; and

         (g)   The general plan view drawing of division (D)(2) above shall indicate the areas of directly connected impervious areas and any offsetting landscaped areas as defined in § 164.023(E).

   (F)   Floodplain submittal. The applicant shall obtain approval from IDNR-OWR and FEMA for all new base flood and floodway determinations for those cases in which their permitting authority applies or as noted in § 164.061 of this chapter. The site development permit will not be issued until the approval is received. Documentation supporting a finding that the proposed development is in compliance with §§ 164.060 and 164.061 shall be submitted with the application. At a minimum, the following material shall be submitted for approval with the application:

      (1)   Regulatory floodplain boundary determination:

         (a)   Provide source of flood profile information; and

         (b)   Provide all hydrologic and hydraulic study information for site-specific floodplain studies, unnumbered Zone A area elevation determinations and floodplain map revisions.

      (2)   Floodway hydrologic and hydraulic analyses for the following conditions:

         (a)   Existing conditions (land used and stream systems);

         (b)   Proposed conditions (land used and stream systems);

         (c)   Tabular summary of 100-year flood elevations and discharges for existing and proposed conditions;

         (d)   Calculations used for model development; and

         (e)   Hydraulic/hydrologic computer model input/output.

      (3)   Floodplain fill and compensatory storage calculations for below and above ten-year flood elevation up to the base flood elevation:

         (a)   Tabular summary for below and above ten-year flood elevation of fill, compensatory storage and compensatory storage ratios provided in proposed plan; and

         (b)   Cross-sections used for the above calculations.

      (4)   Floodproofing measures:

         (a)   Narrative discussion of floodproofing measures including material specifications, calculations and design details, operation summary; and

         (b)   Ensure structures built on fill in or near special flood hazard areas are reasonably safe from flooding (see TB 10-01 published by FEMA).

      (5)   Flood easements when required by this chapter.

   (G)   Wetland submittal requirements.

      (1)   In addition to all other site development permit requirements, wetland permit submittal requirements depend upon whether the development is within waters of the United States or isolated waters of the county as provided below. The applicant shall provide a statement of wetland determination as to which wetlands on the development site are isolated waters of the county or waters of the United States to the United States Army Corps of Engineers (Corps) for a jurisdictional determination. A copy of the jurisdictional determination shall be included with the wetland submittal.

      (2)   For wetland impacts to waters of the United States or isolated waters of the county, the following information is required:

         (a)   Wetland delineation and wetland determination report;

         (b)   A United States Army Corps permit for the proposed development or a letter from the Corps stating that the proposed development does not require Corps authorization;

         (c)   Buffer area requirements as specified in § 164.067(D);

         (d)   A cover letter signed by a qualified wetland professional, that provides a clear project purpose and need statement, a description of the proposed activity, area (in acres) of wetland and/or buffer impact;

         (e)   Buffer area requirements as specified in this chapter;

         (f)   A delineation of the wetlands consistent with the requirements provided in § 164.067(C) of this chapter, signed by a qualified wetland professional;

         (g)   A statement on the occurrence of any high quality aquatic resource (HQAR) on or adjoining the development, signed by a certified wetland specialist;

         (h)   Documentation that the development is in compliance with the State Department of Natural Resource’s endangered species consultation program and the State Natural Areas Preservation Act;

         (i)   Documentation that the development is in compliance with the United States Fish and Wildlife Service’s consultation program under the Endangered Species Act;

         (j)   A mitigation plan meeting the requirements of this chapter;

         (k)   A discussion, hydrology calculations or other supporting information to document that on-site preserved wetlands and off site wetlands will not be impacted either from adverse changes in hydrology or pollutant/sediment loading or erosion;

         (l)   A copy of the natural resources information report (NRI) for development that is required to obtain a NRI performed by the County Soil and Water Conservation District;

         (m)   A narrative of the alternative measures taken to avoid, minimize, or mitigate for wetland impacts to isolated waters of the county; and

         (n)   Shoreline and streambank erosion restoration that meet the requirements contained in divisions (J) and (K) below are exempt from submittal requirements contained in this division.

   (H)   Permit exceptions.

      (1)   The provisions of this chapter shall not apply to:

         (a)   Emergency work necessary to preserve life or property; when emergency work is performed under this section, the person performing it shall report the pertinent facts relating to the work to the County Land Use Department within ten working days after commencement of the work and shall thereafter obtain a site development permit and shall perform that work as may be determined by the agency to be reasonably necessary to correct any impairment to the watercourse, lake, pond, floodplain or wetland;

         (b)   Work consisting of the operation, repair or maintenance of any lawful use of land existing on the date of adoption of this chapter;

         (c)   Lands adjacent to farm ditches if:

            1.   The lands are not adjacent to a natural stream or river;

            2.   Those parts of the drainage ditches adjacent to such lands were not streams before ditching; or

            3.   The lands are maintained in agricultural uses without buildings and structures.

      (2)   Where farm ditches are found to contribute to adverse environmental impacts or hazards to persons or property, the County Land Use Department may request submittal of a stormwater management application. The County Land Use Department may also require that linings, bulkheads, dikes and culverts be removed to mitigate hazards or that other mitigating measures be taken, such as the maintenance of a natural vegetation buffer strip.

   (I)   Conditions and restrictions for permitting stream modification. Stream modification is subject to the following conditions and restrictions:

      (1)   Water quality, habitat and other natural functions must be improved by the modification;

      (2)   No HQAR habitat area may be destroyed; and

      (3)   All of the requirements of a site development permit must be provided as well as the information required in division (K) below.

   (J)   Required content of stream modification/ relocation plan. Stream relocation may be permitted in accordance with a stream relocation plan that provides, to the extent possible, for:

      (1)   The creation of a natural meander pattern, pools, riffles and substrate;

      (2)   The formation of gentle side slopes (at least three feet horizontally per one foot vertically), including installation of erosion control features;

      (3)   The utilization of natural materials wherever possible;

      (4)   The planting of vegetation normally associated with streams, including primarily native riparian vegetation that is capable of holding banks and soil in place;

      (5)   The creation of spawning and nesting areas where appropriate;

      (6)   The re-establishment of the native fish population where appropriate;

      (7)   The restoration of water flow characteristics compatible with native fauna habitat areas, where appropriate;

      (8)   The filling and revegetation of the prior channel;

      (9)   A proposed phasing plan, specifying time of year for all project phases;

      (10)   Plans for sediment and erosion control; and

      (11)   Establishment of a low-flow channel which reflects the conditions of a natural stream.

   (K)   Criteria for permitting armoring of channels and banks. Armoring in the form of bulkheads, riprap or other materials or devices is not permitted except in accordance with a site development permit as well as the following:

      (1)   The use of revegetation and gradual bank slopes are practicable;

      (2)   Significant erosion cannot be prevented in any other way;

      (3)   The bulkhead or other device is not placed within a wetland, or between a wetland and a lake or pond except where necessary to resolve a health, safety or welfare issue; and

      (4)   The bulkhead, riprap or other device will minimize the transmittal of wave energy or currents to other properties.

   (L)   Criteria for permitting the use of culverts. Culverts are not permitted in streams except in accordance with a site development permit as well as the following:

      (1)   Where a culvert is necessary for creating access to a property (use of culverts as a convenience, in order to facilitate general site design, is not to be considered);

      (2)   The culvert must allow passage of fish inhabiting the stream, and accommodate the 100-year flood event without increasing upstream flooding, except where a restricting culvert is desirable as part of an overall storm and floodwater management plan;

      (3)   The culvert must be maintained free of debris and sediment to allow free passage of water, and if applicable, fish; and

      (4)   The stream bottom should not be significantly widened for the placement of a culvert as this situation will likely increase erosion and downstream sedimentation; if multiple culverts must be installed, one culvert should be at the level of the bottom of the stream and the others at or above normal water elevation.

   (M)   Stream maintenance easement. The applicant shall grant an access easement for stream maintenance purposes to county over a 25 feet wide strip adjacent to the stream bank except in the case where the property owner is another unit of government.

   (N)   Effect on other permits. The issuance of a site development permit under the provisions herein shall in no way affect the owner’s responsibility to obtain the approval required by any other statute, ordinance, or regulation of any state agency or subdivision thereof, or to meet other county ordinances and regulations. Where state and/or federal permits are required, a site development permit will not be issued until they are obtained.

(Ord. 10-164, passed 6-17-2010)

§ 164.083 SUBMITTALS PRIOR TO PERMIT ISSUANCE.

   The following additional submittals are required prior to issuance of the site development permit.

   (A)   Performance security. Performance security in accordance with §§ 164.180 through 164.183 shall be required prior to permit issuance.

   (B)   Maintenance schedule and funding. A completed maintenance schedule for the stormwater management facilities and special management areas, in accordance with §§ 164.100 through 164.105 shall be submitted along with identification of the entity responsible for maintenance and funding and back-up funding sources for maintenance in accordance with § 164.105.

(Ord. 10-164, passed 6-17-2010)