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(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.
(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)