(A) Purpose. The regulations of this subchapter are intended to accomplish the following purposes:
(1) Meet the requirements of The Rivers, Lakes and Streams Act, 615 ILCS 5/18g;
(2) Prevent additional harm due to periodic flooding including loss of life and property and threats and inconveniences to public health, safety, and welfare;
(3) Assure that new development does not increase flood and drainage hazards to others, or create unstable conditions susceptible to erosion;
(4) 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;
(5) Protect, conserve, and promote the orderly development of land and water resources;
(6) Protect buildings and improvements to buildings from flood damage to the greatest extent possible;
(7) Conserve the natural hydrologic, hydraulic, water quality and other beneficial functions of flood-prone areas, regulatory floodplains;
(8) Prevent additional disruption of the economy and governmental services due to stormwater and flood drainage;
(9) Maintain eligibility for the county in the National Flood Insurance Program by meeting or exceeding its requirements and thus make federally subsidized flood insurance available at reduced rates. Comply with the rules and regulations of the National Flood Insurance Program codified as 44 C.F.R. parts 59 through 79, as amended; and
(10) Conserve the natural hydrologic, hydraulic, water quality and other beneficial functions of wetlands by having, at a minimum, no net loss of wetlands in the county, and further these beneficial functions wetlands by having an objective of a net gain of wetland functions as specified in the Wetland Preservation and Restoration Plan component of the Lake County Comprehensive Stormwater Management Plan.
(B) Applicability. A site development permit is required for any development that meets any one of the following criteria:
COMMENTARY: In order to prevent “phasing” of development to circumvent the intent of these regulations, when a proposed development activity will occur on a lot or parcel of land that has contiguous lots or parcels of lands owned in whole or in part by the same property owner, then the criteria as defined in the “Applicability” 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 the “Applicability” section, then a site development permit will be required. |
(1) Is located on a property containing a regulatory floodplain;
(2) Is located in a flood-prone area with 100 acres of tributary drainage area or more;
(3) Is located in a depressional storage area with a surface area of one-fourth acre or more, or with a storage volume of 0.75 acre-feet or more for the base flood;
(4) Creates a wetland impact within an area defined as waters of the United States or isolated waters of Lake County;
(5) Modifies the flood-prone area of a water body where the tributary drainage area is 20 or more acres;
(6) Includes the total land area of an ownership parcel that results in:
(a) More than one acre of new impervious area; or
(b) More than three acres of hydrologically disturbed area, unless the total new impervious surface area is less than one-half acre; or
(c) An impervious surface area ratio of 50% or greater, unless the total new impervious surface area is less than one-half acre. The term “new”, as used in this subsection (B)(6), refers to impervious or hydrologically disturbed area created after the original effective date of the Watershed Development Ordinance (October 13, 1992). Redevelopment of previously developed sites shall maintain existing storage volume and shall not increase the rate of runoff from the site. The applicant shall provide supporting data and calculations to the satisfaction of the Planning, Building and Development Director to ensure the site design either provides a watershed benefit or meets the requirements of § 151.146(C)(2). New development on partially developed sites shall meet the release rate criteria in § 151.146(C) for the new development, if the new development exceeds the thresholds in subsections (B)(6)(a), (B)(6)(b), or (B)(6)(c) above.
(7) Any site disturbance on any undeveloped parcel, or the undeveloped portion of any parcel that consists of any of the following:
(a) Any excavation, filling, or combination of excavation or filling that will exceed 500 cubic yards;
(b) Any excavation, filling, or combination of excavation or filling that will exceed three feet in vertical depth or height at its deepest point measured from the natural ground surface; any excavation, filling, or combination of excavation or filling that will exceed an area of 1,000 square feet;
(c) Removal of plant cover from an area exceeding 1,000 square feet; or
(d) Any development within an area previously identified by the county as posing a unique drainage concern. For proposed developments within those areas, an inspection of the site shall be conducted and the Planning, Building and Development Director shall determine whether a site development permit is required based on the site conditions.
(8) For all nonresidential development, with the exception of interior alterations, a site development permit shall be required unless, following an inspection of the site, the Planning, Building and Development Director determines that, based on the site conditions, no permit is warranted.
(9) Any activity to a building in a special flood hazard area (SFHA) as described in FEMA publication 480 National Flood Insurance Program Flood Management Requirements.
(C) Exempted development.
(1) All development shall comply with minimum federal, state, and local regulations. No development is exempt from the floodplain, floodway, wetland, and soil erosion and sediment control provisions of this chapter. An exemption request under subsection (C)(2) below shall be submitted in writing by the applicant to the Planning, Building and Development Director for an exemption from specific performance standards of this chapter. The applicant’s exemption request shall itemize each chapter provision that is requested for exemption. After review and verification by the Planning, Building and Development Director that subsection (C)(2) below is met, the specific chapter provision exemptions may be granted.
(a) Final plats, site development permits, or current building permits approved prior to October 18, 1992 if the stormwater management facilities are installed and functioning and in compliance with all applicable stormwater regulations then in effect. This item is applicable to § 151.146(H)(5) (buffer areas) only.
(b) Final plats, planned unit developments, site development permits or current building permits approved between October 18, 1992 and April 13, 2021, if the approved plans and designs are in conformance with the pre-October 13, 2020, ordinance provisions. That portion of any final plat, planned unit development, site development permit, or current building permit which is amended after the effective date of this chapter and which affects the stormwater management system is not exempt from the provisions of this chapter.
(c) Re-subdivision of commercial or industrial subdivisions identified under subsection (C)(1)(a) above, provided that the stormwater management facilities are installed and functioning and there is no increase in impervious surface area permitted. Re-subdivision of commercial or industrial subdivisions identified under subsection (C)(1)(b) above, provided there is no increase in impervious surface area beyond that which was originally approved.
(d) Public road development on county highways and township roads, provided that plans will be submitted to the Lake County Stormwater Management Commission to ensure compliance with applicable stormwater management, soil erosion and sediment control and floodplain and wetland requirements.
(e) The maintenance of existing buildings and facilities such as resurfacing of roadways when the road elevation is not increased.
(2) If eligible under subsections (C)(1)(a), (C)(1)(b), or (C)(1)(c) above, the applicant may submit a written request to the Planning, Building and Development Director for an exemption from specific performance standards of this chapter. The applicant’s exemption request shall itemize each ordinance provision that is requested for exemption.
(3) A site development permit shall not be required for any of the following:
(a) The maintenance of existing buildings and facilities such as resurfacing of roadways when the road elevation is not increased;
(b) Practices associated with local food gardens that do not involve filling or grading;
(c) Fence installation, pole placement, drilling, or other minor auxiliary construction as long as the development activity is not located in a regulatory floodway, wetland, or water body.
(D) Classification of development. All activities requiring a site development permit shall be classified as “major” or “minor” developments, in accordance with the following definitions.
(1) Major development. A “major” development is any development subject to site development permit requirements that meets any one of the following criteria:
(a) Is located in any portion of a regulatory floodway or floodplain, with compensatory storage requirement, is located in any depressional storage area that has a surface area of one-fourth acre or more, or that has a volume larger than 0.75 acre-feet;
(b) Creates a wetland impact to waters of the United States or isolated waters of Lake County exceeding the isolated wetland impact mitigation thresholds in § 151.146(M)(4);
(c) Modifies a water body where the tributary drainage area is greater than 100 acres, with compensatory storage requirement; or
(d) Requires detention per § 151.146(C).
(2) Minor development. A “minor” development is any development subject to site development permit requirements that is not a “major” development, provided that the Planning, Building and Development Director may classify any development as a “major” development if that the Planning, Building and Development Director determines that the nature of the proposed work warrants the “major” development classification.
(E) Review and approval procedure.
(2) Application. Applications for site development permits shall be made in person in the Planning, Building and Development Department.
(3) Staff review and action. Planning, Building and Development Department staff shall review each site development permit application and, within 30 days of receipt of a complete application, act to approve, approve with conditions, or deny the application. Failure of the Planning, Building and Development Director to act within the 30-day period shall constitute a denial of the application, unless the applicant agrees to an extension of time. If the applicant fails to provide information requested by the Planning, Building and Development Director within three months of the request, the application shall be void, unless the time is extended by the Planning, Building and Development Director.
(4) Other approvals required; permit issuance before final approval.
(a) No site development permit shall be issued by the Planning, Building and Development Director unless the development, including but not limited to subdivisions and planned unit developments, has been approved by all applicable county agencies. However, in the following instances, a site development permit may be issued prior to final approval provided that:
1. The final engineering plans are approved by the appropriate county agencies, and the development demonstrates compliance with applicable application requirements and performance standards; and
2. All applicable application requirements and performance standards have been met, except for obtaining any required state and federal approvals.
(b) A request for commencement of grading activities may be made for a development site prior to the issuance of a site development permit. The proposed grading activity may commence with written approval from the Planning, Building and Development Director of the earth change approval plan that delineates the activities specifically allowed including appropriate soil erosion and sediment control measures. The written approval will be in the form of a permit. The permit application will state the conditions and limitations of the proposed grading activities. No permit may be issued and no development activity may occur in a regulatory floodplain, except for excavations outside of the regulatory floodway and which do not require an Illinois Department of Natural Resources, Office of Water Resources permit, wetland, or in those portions of the site for which this chapter requires that state and federal permits be issued, except for Illinois Environmental Protection Agency sewer and water extension permits. (See Appendix G for a partial list of agencies from which permits may be required.)
(5) Financial assurances.
(a) For nonresidential development that meets the criteria of § 151.145(B)(6) and for any development where the Planning, Building and Development Director requires, the applicant shall file with the county a performance assurance satisfactory to the Lake County State’s Attorney for an amount equal to one 130% of the total cost of improvements including the cost of landscaping, soil erosion and sediment control measures, and all engineering costs and inspection fees, based upon the consulting engineer’s estimate of cost. Government entities such as townships, schools, park districts, and the like are exempt from this requirement.
(b) A maintenance assurance if required by the county, shall be deposited with the county prior to the release of any performance assurance held by the county for the time period and in the amount specified by the Planning, Building and Development Director to cover the cost of failure or repair of improvements installed on the site, including landscaping, wetland restoration/mitigation, and soil erosion and sediment control measures.
(c) A letter certifying the as-built conditions shall be submitted by the consulting engineer prior to the release of any performance assurance. In addition, the Planning, Building and Development Director may require deed restrictions, covenants, easements, or any other documents to ensure proper enforcement of the site development regulations.
(d) The assurance may be drawn at any time the permittee fails to comply with the requirements of this or any other county ordinance or with the approved site development plans or with the approved timeframe for site development activities.
(6) As-built drawings. As-built drawings, signed and sealed by a Licensed Professional Engineer, shall be required for all major developments, public road developments, and other types of development as determined by the Planning. Building and Development Director (such as those developments that affect stormwater runoff rates or volume, impact wetlands or wetland buffers, or are adjacent to floodplains). As-built drawings and supporting information shall clearly show all as-built conditions, including, but not limited to:
(a) Topographic spot elevations and contours for overland flow paths, detention ponds, storage facilities, and building pads;
(b) Detention pond restrictor size, invert elevation, emergency overflow size, and elevation;
(c) Verification of required native vegetation planted (seed tags, invoices);
(d) Storm sewer sizes, inverts;
(e) Drain tile information provided from the Subsurface Drainage Inventory, or identified during construction as follows: location, connection, size, material, and inverts for those drain tiles that are part of the stormwater management system;
(f) Other information required under this chapter;
(g) Applicable calculations or other information verifying conformance with the permitted plan set;
(h) Low floor and low opening elevations of structures. Low opening sizes where vents are required; and
(i) Benchmark information.
(j) Elevation of the bottom of the lowest horizontal structural member of a lowest floor, and whether the structure has a basement, for structures located in a coastal high hazard area.
(7) Inspections. The Planning, Building and Development Director may inspect site development at any stage in the construction process. For major developments, the Planning, Building and Development Director shall conduct site inspections, at a minimum, at the end of the construction stages (E)(7)(a)1. through 7. listed below. Construction plans approved by the Planning, Building and Development Director shall be maintained at the site during progress of the work. In order to obtain inspections in accordance with the following schedule, the permittee shall notify the Planning, Building and Development Director at least two full working days before the inspection is to be made. The Designated Erosion Control Inspector shall conduct inspections and document as described below, at a minimum, at the intervals in subsections (E)(7)(a)1. and (E)(7)(a)6. listed below, for those developments that require a Designated Erosion Control Inspector, until permanent stabilization and Planning, Building and Development Director approval of appropriate as-built documentation and drawings.
(a) Recommended inspection intervals are listed below:
1. Upon completion of installation of sediment and runoff control measures (including perimeter controls and diversions), prior to proceeding with any other earth disturbance or grading;
2. After every seven calendar days or storm event with greater than one-half inch of rainfall or liquid equivalent precipitation;
3. After final stabilization and landscaping, prior to removal of sediment and erosion controls;
4. After removal of erosion and sediment controls;
5. Designated Erosion Control Inspector inspections may be performed at a reduced frequency, at the discretion of the Planning, Building and Development Director, for projects with a valid Site Development Permit, that are permanently stabilized, and are entering a prolonged period of inactivity. Designated Erosion Control inspections shall only be required after storm events with greater than 0.5 inch of rainfall or liquid equivalent precipitation.
6. If a wetland mitigation area is constructed as part of the site development permit, the Lake County Stormwater Management Commission or Isolated Water of Lake County-Certified Community’s Certified Wetland Specialist shall, at a minimum, perform the following inspections:
a. Inspection by a certified wetland specialist after mitigation areas have been final graded and before seeding or plant installation;
b. Inspection by a certified wetland specialist after seeding or plant installation; and
c. At a minimum, annual inspections by a certified wetland specialist during the five-year monitoring and maintenance period for wetland mitigation areas.
(b) Minimum inspection documentation shall include: site observations and a sufficient number of photos depicting the conditions of the entire site, inspector’s name, date and time of the inspection, status of perimeter control, and site outlet observations.
(8) Special precautions.
(a) If at any stage of the grading of any development site the Planning, Building and Development Director determines that the nature of the site is such that further work authorized by an existing permit is likely to imperil any property, public way, stream, lake, wetland, or drainage structure, the Planning, Building and Development Director may require, as a condition of allowing the work to be done, that reasonable special precautions be taken as is considered advisable to avoid the likelihood of the peril. “Special precautions” may include but shall not be limited to a more level exposed slope, construction of additional drainage facilities, berms, terracing, compaction, cribbing, installation of plant materials for erosion control, and recommendations of a Licensed Geotechnical Engineer and/or Licensed Professional Geologist which may be made requirements for further work.
(b) Where the Planning, Building and Development Director determines that storm damage may result or has resulted because the grading on any development site is not complete, work may be stopped and the permittee required to install temporary structures or take any other measures as may be required to protect adjoining property or the public safety. On large developments or where unusual site conditions prevail, the Planning, Building and Development Director may require that the operations be conducted in specific stages so as to ensure completion of protective measures or devices prior to the advent of seasonal rains.
(c) In the event that a stormwater detention or conveyance facility fails to function as designed because of improper or inadequate maintenance, the Planning, Building and Development Director shall inspect the facility and compel corrective action. To compel corrective action, the Planning, Building and Development Director shall provide written notification to the property owner indicating: (1) corrective actions required to return the facility to functional order; or (2) additional engineering plans, reports or calculations required to identify the problem or engineer a solution, and that the plans, reports, or calculations shall be submitted for review and approval.
(9) Permit expiration.
(a) A site development permit shall be issued for a time period of not more than two years and shall expire by limitation. The Planning, Building and Development Director may grant an extension of time, not to exceed one year, if the Planning, Building and Development Director determines, based on information provided by the permit holder, that unusual difficulties have prevented work being started or completed within the specified time limits. A written extension request and permit extension fee (revised May 9, 2006) must be filed by a permit holder before expiration of the permit. If the work authorized by such permit has not been commenced within six months of permit issuance, the permit shall lapse and be of no further effect unless a start work extension request has been filed within six months of permit issuance (revised May 9, 2006). If the permit expires, a new permit application review and fees shall be required for the completion of the project and the applicant shall comply with the current ordinance requirements.
(b) A permit that includes a structure located within the regulatory floodplain, or will be located within the regulatory floodplain, shall be terminated without the possibility of an extension, if the start of construction is not commenced within 180 days of the permit issuance date unless the structure is compliant with the following:
1. Any modification to National Flood Insurance Program regulations after permit issuance; or
2. Any modification to a Federal Emergency Management Agency Flood Insurance Rate Map or Flood Insurance Study after permit issuance.
(c) For the purposes of this subsection, “start of construction” means the commencement of any repair, reconstruction, rehabilitation, addition, or improvement of a structure; or the first placement of permanent construction of a structure on a site, such as the pouring of slab or footings, the installation of piles, the construction of columns, or any work beyond the stage of excavation; or the placement of a manufactured home on a foundation. Permanent construction does not include land preparation, such as clearing, grading and filling; nor does it include the installation of streets and/or walkways: nor does it include excavation for a basement, footings, piers, or foundations or the erection of temporary forms; nor does it include the installation on the property of accessory buildings, such as garages or sheds not occupied as dwelling units or not part of the main structure.
(10) Revocation of permit. In the event any person holding a site development permit violates the terms of the permit, or conducts or carries on the site development in a manner that adversely affects the health, welfare, or safety of persons residing or working in the vicinity of the subject property, or conducts or carries on the site development in a manner that is materially detrimental to the public welfare or injurious to property or improvements in the vicinity, the Planning, Building and Development Director shall revoke or suspend the site development permit in accordance with the provisions of § 151.253.
(11) Refunds. Refunds of site development application and permit fees are granted in accordance with the Planning, Building and Development Department fee refund policy. (County Board approved.)
(12) Retention of plans. Plans, specifications, and reports for all site development permits shall be retained by the Planning, Building and Development Department.
(F) Application requirements. The site development permit application requirements of this section establish different application requirements for major and minor developments.
(1) Applications for minor developments. The Planning, Building and Development Director shall determine what information is required to ensure compliance with the purpose and intent of this chapter. This information may include but shall not be limited to the following:
(a) A completed site development permit application signed by the property owner or owner’s agent and, when required a licensed professional engineer and certified wetland specialist.
(b) A topographic survey and/or grading plan showing proposed (min. 1% grade) and existing contours, and the limits of grading prepared, signed and sealed by an Illinois Licensed Land Surveyor or Licensed Professional Engineer.
(c) A brief drainage report describing the characteristics of the existing and proposed drainage systems including all discharge points, collection, conveyance, and storage facilities, and any calculations used to determine stormwater quantities, flow rates and/or storage volumes.
(d) A site drainage plan, which depicts drainage features, overland flow paths, stormwater management system components, flood-prone areas, regulatory floodplains, wetland boundaries, buffer areas, existing and proposed septic systems and wells. A capacity analysis of the above stormwater system components may be required by the Planning, Building and Development Director.
(e) An area drainage plan locating the proposed development in the watershed.
(f) A description and depiction of measures to be taken to control erosion (sedimentation and erosion control plan).
(g) Existing and proposed typical cross-sections and profiles of all components of the stormwater management system including, but not limited to swales, berms, and detention ponds.
(h) For all proposed temporary soil stockpiles, the location, dimensions, and a schedule for removal.
(i) All plans and calculations that are prepared by a licensed professional engineer pursuant to this section shall be signed and sealed by the engineer.
(j) A description of the anticipated dates of initiation and completion of activity.
(k) An exhibit for review that displays all deed or plat restrictions of record or to be recorded for the stormwater management system.
(l) The federal, state, and local permit requirements of subsections (F)(2)(h) and (F)(2)(i) are required when applicable to the development site and subsections (F)(2)(f)3. and (F)(2)(g) shall be required when requested by the Planning, Building and Development Director.
(m) A wetland submittal, if required, under § 151.146(M).
(n) For permits required only in accordance with subsection (B)(9) above documentation shall be submitted towards the determination of a substantial improvement. Other submittal requirements may be waived.
(2) Applications for major developments. The following application requirements shall be met unless the Planning, Building and Development Director determines that an item is unnecessary to ensure compliance with the purpose and intent of this chapter:
(a) Name and legal address of the applicant. Common address, legal description, and/or the parcel identification numbers for the property where the development will take place. Mailing address of the property owner;
(b) The name, company name, title, address, phone and fax numbers of all consultants involved in the design and engineering of the proposed development;
(c) A vicinity map depicting the location of the subject development in relation to major roads, natural features, municipalities, and the like along with the parcel identification numbers of all parcels comprising the proposed development;
(d) A map showing the location of the subject development in its watershed as depicted on U.S. Geologic Survey maps. The extent and area of each watershed affecting the design of stormwater detention and conveyance facilities within the subject development;
(e) Site development plans: the information required by this subsection (F)(2) shall be presented at any normal scale up to and including one inch equals 100 feet (1:100) that is convenient to portray the required information on a sheet size not to exceed 24 by 36 inches and shall be bound into a package that includes the following sheets:
1. A topographic survey of the existing conditions of the development site which includes the following information:
a. Existing contour lines at not greater than one-foot intervals. The reference benchmark shall be cited on the plan. Spot elevations shall be provided at all breaks in grade and where necessary to indicate grade changes in areas of shallow topography. The source and/or preparer of the topographic survey shall be recognized on the plan. All elevations shall be referenced to North American Vertical Datum of 1988 (NAVD 88), which supersedes the NGVD 29 datum used prior to September 18, 2013;
b. The existing layout of all lots, parcels, road rights-of-way, and easements, including lot numbers and street names, on the subject site and on all adjoining parcels;
c. The location of streams, drainageways, and other floodwater runoff channels, their normal channels, and extent of the floodplains at the established high-water elevation, and the limits of the floodway, all properly identified;
d. The normal shoreline of lakes, ponds, and detention basins, their easements, floodplains, and lines of inflow and outflow, if any;
e. The location, size, and flowline elevation of all existing storm and sanitary sewers, and water mains, if any, of record;
f. The location of field tiles and their sizes which are on file with the Soil and Water Conservation District of Lake County or are known by the developer;
g. The location of all existing individual sewage disposal systems, if any, of record;
h. The location of all existing wells, if any, of record;
i. Natural and other groundwater sources such as seeps, springs, flowing, and other artesian wells, that are visible or are of record;
j. The soil conditions as indicated in the Soil Survey, Lake County, Illinois, or as determined by an on-site soil survey. The soil boundaries shall be drawn on the plan and the soil designation numbers shall be shown in the area where each soil mapping unit exists; and
k. The location, boundaries and type of predominate vegetation on the development site.
2. A drainage plan prepared as an overlay of the topographic survey described above, and including the following information:
a. Proposed contour lines at not greater than one-foot intervals. Proposed spot elevations shall be provided at all breaks in grade and where necessary to indicate grade changes in areas of low relief;
b. The limits of all watershed boundaries, drainage areas, points of discharge, velocity of flow, and flow quantities;
c. An indication of the direction of water flow in all proposed and existing swales and drainageways, including the slope of channel and existing and proposed typical cross-sections and profiles;
d. The location of all existing streams and floodplains to be maintained, and proposed channels to be constructed, including specification and dimensions of proposed channel modifications, locations and orientation or cross-sections and profiles;
e. (i) Typical cross-sections of all existing detention basins to be maintained, enlarged, or otherwise altered and proposed basins and their design, showing the following:
(I) Length, width, dimension;
(II) Berm elevation;
(III) Water elevation - normal and high;
(IV) Bottom slope elevation; and
(V) Control structure details (outlets, restrictors, spillways, and the like).
(ii) The typical cross-sections also shall show the elevation of the existing land surface and the proposed changes thereto, together with the calculated high water elevations expected from stormwater overland flow depth and path, and the relationship of structures, streets, and other utilities.
f. Plans and profiles of all proposed street storm sewers and other storm drains including their slope, type, size, outfall and outlet locations, and elevations, receiving streams or channels and their high water elevations;
g. Proposed culverts and bridges to be built, their materials, elevations, waterway openings; and
h. Cross-sections of all existing and proposed channels or other open drainage facilities, showing the elevation of the existing land and the proposed changes thereto, together with the calculated high water elevations expected from stormwater overland flow depth and path, and the relationship of structures, streets, and other utilities. The elevations of lowest floor or lowest adjacent grade for structures shall be included on the development plan as applicable. Refer to the UDO sections on overland flow paths (§ 151.146(H)(3)), floodplain building protection requirements (§ 151.149(H)) and flood table land development (§ 151.153), for elevation requirements of structures within or adjacent to floodprone areas.
3. A soil erosion and sediment control plan showing all measures appropriate for the development as approved by the Planning, Building and Development Director, to meet the objectives of this chapter throughout all phases of construction and permanently after completion of development of the site, including:
a. Location and description, including standard details, of all sediment control measures and design specifics of sediment basins and traps, including outlet details. The drainage area tributary to each sediment control measure shall be delineated on the soil erosion and sediment control plan;
b. Location and description of all soil stabilization and erosion control measures, including seeding mixtures and rates, types of sod, method of seedbed preparation, expected seeding dates, type and rate of lime and fertilizer application, kind and quantity of mulching for both temporary and permanent vegetative control measures, and types of non-vegetative stabilization measures;
c. Location and description of all runoff control measures, including diversions, waterways, and outlets;
d. Location and description of methods to prevent tracking of sediment off-site, including construction entrance details, as appropriate;
e. Description of dust and traffic control measures;
f. Locations of stockpiles and description of stabilization methods;
g. Description of off-site fill or borrow volumes, locations, and methods of stabilization;
h. Provisions for maintenance of control measures, including type and frequency of maintenance, easements, and estimates of the cost of maintenance;
i. Identification (name, address, and telephone) of the person(s) or entity which will have legal responsibility for maintenance of erosion control structures and measures during development and after development is completed; and
j. A written narrative description of the proposed phasing (construction sequencing) of development of the site, including stripping and clearing, rough grading and construction, and final grading and landscaping. Phasing should identify the expected date on which clearing will begin, the estimated duration of exposure of cleared areas, and the sequence of installation of temporary sediment control measures (including perimeter controls), clearing and grading, installation of temporary soil stabilization measures, installation of storm drainage, paving streets and parking areas, final grading and the establishment of permanent vegetative cover, and the removal of temporary measures. It shall be the responsibility of the applicant to notify the Planning, Building and Development Director of any significant changes which occur in the site development schedule after the initial erosion and sediment control plan has been approved.
(f) Site development report: the information required by this subsection (F)(2) shall be presented on eight and one-half by 11-inch paper and shall be bound into a report which includes the following:
1. A drainage report describing the hydrologic and hydraulic analyses performed for the subject development, which includes the following information:
a. A brief description of the proposed development including the purpose of the proposed development activities and the anticipated initiation and completion dates of proposed activities;
b. A brief description of the methodology, assumptions, and sources used in the hydrologic and hydraulic analyses of site drainage;
c. The extent and area of each tributary watershed to the drainage channels in the development, and the names of all streams and other bodies of water affected by the development;
d. A section in the hydrologic and hydraulic analysis report describing how the Runoff Volume Reduction requirements (as described in § 151.146(D)) are incorporated into the development site plan. The section shall include the rationale for not selecting approaches with higher preference. The section shall also provide supporting calculations for meeting the runoff volume reduction requirements;
e. The percentages of existing and proposed areas of impervious surface, the existing and proposed amount of runoff, and the existing rate of stormwater release. This shall include documentation of the design volumes and rates of the proposed runoff for each portion of the tributary watershed to the drainage system and the effects the improvements will have upon the receiving channel and high water elevations. Runoff calculations shall include all discharges entering the site from upstream areas;
f. For detention facilities, a section 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 two-year, 24-hour and the 100-year, 24-hour storm events under existing and developed conditions; and
g. If the soil mapping submitted for the development indicates the soils classified as a hydric soil (USDA/NRCS Soil Classification), then the applicant shall provide site- specific soil mapping performed by a certified soil classifier or geotechnical investigation for the development. No buildings or parking lots shall be constructed on these soils unless appropriate building methods, such as pilings, caissons or removal and replacement of unsuitable soils, as approved by the Planning, Building and Development Director, are used to provide and protect a suitable building foundation.
Development that is exempted from this requirement is any development activity not resulting in the construction of a building or parking lots.
2. A soil erosion and sediment control report which includes the following information:
a. A statement which names the party legally responsible for maintenance of erosion control measures during and after construction. The statement shall include the responsible party’s name, address and telephone number;
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 re-vegetation measures;
c. A construction schedule which indicates the start and finish dates for:
(i) Installation and maintenance of erosion control measures;
(ii) The clearing of vegetation and stripping and stockpiling of topsoil;
(iii) Rough grading and construction of stormwater detention and conveyance facilities;
(iv) Topsoil respreading, final grading and site restoration; and
(v) Maintenance of improvements.
d. A schedule for the removal of all proposed temporary soil stockpiles.
3. A maintenance plan for the ongoing maintenance of all stormwater management system components, including wetlands, is required prior to plan approval. The plan shall be referenced in the recorded deed or plat restriction document associated with the stormwater management system. The plan shall include:
a. Maintenance tasks and the type and frequency of maintenance of all components of the stormwater management system, including existing and replaced drain tiles within the ownership parcel which are part of the stormwater management system;
b. The party responsible for performing the maintenance tasks;
c. A description of all permanent public or private access deed- or plat-restricted areas for all stormwater management system components for the development;
d. A description of dedicated sources of funding for the required maintenance; and
e. Measures to prohibit the dumping, depositing, dropping, throwing, discarding, or leaving of construction material debris and all other illicit discharges into the stormwater management system and measures to be in continued compliance with IEPA NPDES Permit No. ILR40.
(g) The application form, development plans, and stormwater reports shall meet the requirements of this section. All plans, calculations and other documentation shall be signed and sealed by a licensed professional engineer. Additionally, the engineer shall provide a letter, bearing his or her seal and signature, which certifies that all plans, calculations and other documentation submitted by him or her have been prepared and are in full compliance with all applicable county ordinances. However, public trail and park facility projects that do not involve the placement of structures or fill can be submitted without the certification or seal of a licensed professional engineer;
(h) A copy of a Natural Resource Inventory (NRI) shall be submitted by the applicant to the Planning, Building and Development Director for development that is required to obtain a NRI performed by the McHenry-Lake County Soil and Water Conservation District pursuant to state statute 70 ILCS 405/22.02a;
(i) For all development sites requiring a National Pollutant Discharge Elimination System permit, the applicant shall submit a notice of intent (NOI) to the Illinois Environmental Protection Agency to comply with the National Pollutant Discharge Elimination System Stormwater Permit. The approved erosion control plan created pursuant to the requirements of this chapter and the Watershed Development Ordinance shall fulfill the plan requirements in the National Pollutant Discharge Elimination System permit;
(j) A copy of the consultation application to the Illinois Department of Natural Resources shall be submitted by the applicant to the Planning, Building and Development Director for development that is required to comply with the consultant process of the Illinois Endangered Species Protection Act (520 ILCS 10/11) and the Illinois Natural Areas Preservation Act (525 ILCS 30/17);
(k) A wetland submittal, if required, under § 151.146(M); and
(l) A copy of the building plans and cost estimates in accordance with Federal Emergency Management Agency National Flood Insurance Program standards shall be submitted for modifications to existing structures in the Regulatory Floodplain.
1. A copy of building plans shall be submitted for modifications to existing structures in the Regulatory Floodplain: the building plans shall include a comprehensive materials list of all items directly associated with the structure. At the discretion of the Planning, Building and Development Director, the building plans and comprehensive materials list shall be signed and sealed by an Illinois Licensed Architect or Licensed Professional Engineer.
2. A minimum of two cost estimates shall be submitted for modifications to existing structures in the regulatory floodplain, The cost estimates shall reflect the fair market value of all materials and labor directly associated with the structure, including construction management, overhead, and profit costs: the estimates shall correlate with the comprehensive materials list and building plans. At the discretion of the Planning, Building and Development Director, additional supporting cost estimate information shall be submitted.
(3) Dam safety permits. The applicant shall obtain and provide, when applicable to the proposed development, a copy of an Illinois Department of Natural Resources (IDNR), Office of Water Resources (OWR), dam safety permit or a letter stating that a dam safety permit is not required before the applicant requests or obtains a site development permit (see Appendix H for dam safety permit requirements).
(4) Federal, state, and local permits and approvals.
(a) The applicant shall obtain and provide copies of any and all required federal, state, and local permits for development in the regulatory floodplain before the applicant requests or obtains a site development permit. (See Appendix G for a partial list of agencies from which permits may be required.)
(b) Lake County Division of Transportation approval is required prior to the issuance of a site development permit when the property’s access is proposed or existing from a collector or arterial road. (See Appendix B for collector and arterial roads.)
(5) Proposed revisions to base flood elevation or regulatory floodplain boundary. The applicant shall submit, to the Planning, Building and Development Department, the Lake County Stormwater Management Commission, and the Federal Emergency Management Agency, the data required for proposed revisions to the base flood elevation of a regulatory floodplain study or relocation of a regulatory floodway boundary. The applicant shall also submit this data to Illinois Department of Natural Resources, Office of Water Resources, when the tributary area is greater than one square mile.
(6) Ground elevations. The applicant shall provide, when applicable to the development an affidavit or documentation to prove the location of the development relative to the base flood elevation prior to the effective date of the first regulatory floodplain map; and certification that the current ground elevation existed prior to the effective date of the first regulatory floodplain map.
(7) Subsurface drainage tiles. The applicant shall submit a subsurface drainage inventory. The inventory shall include locations of existing farm and storm drainage tiles by means of silt trenching and other appropriate methods performed by a qualified subsurface drainage consultant. All existing drain tile lines damaged during the investigation shall be repaired to their previous working status.
(a) The applicant shall provide a topographical map of the development site showing:
1. Location and depth of each trench and identified to correspond with the tile investigation report and surveyed points where the tile was field staked at approximately 50-foot intervals;
2. Location of each drain tile with a flow direction arrow, tile size, and any connection to adjoining properties;
3. A summary of the tile investigation report showing trench identification number, tile size, material and quality, percentage of the tile filled with water, percentage of restrictions caused by silting, depth of groundwater, and working status; and
4. Name, address, and phone number of person or firm conducting tile location investigation.
(b) Information collected during the Subsurface Drainage Inventory shall be used as part of the design and construction of a stormwater management system that meets the requirements of this chapter.
COMMENTARY: The Technical Reference Manual prepared by the Lake County Stormwater Management Commission and the “Procedures and Standards for Urban Soil Erosion and Sedimentation Control” prepared by the Northeastern Illinois Soil Erosion and Sedimentation Control Steering Committee are references to be used in the preparation of the documents required for submission. |
(Ord., § 8.1, passed 10-13-2009; Ord. passed 10-9-2012; Ord. passed - - ; Ord. 22-1060, passed 8-9-2022; Ord. 23-1056, passed 8-8-2023; Ord. 24-0207, passed 3-12-2024)