11-18-020 Definitions.

   For the purposes of this chapter, unless the context requires otherwise, the following terms, regardless of whether or not they are capitalized, shall have the definitions set forth below:

   Applicant. A person applying for a Stormwater Management Plan approval or an amendment thereto or variance therefrom. An Applicant must be the Owner or Developer of the Regulated Development specified in the Plan.

   Average Dry-Weather Flow. Non-stormwater flow that consists of either (a) sanitary flow as quantified in 35 Ill. Admin. Code, Subtitle C, Chapter II, Part 370, Appendix B (“Table Number 2 – Commonly Used Quantities of Sewage Flows From Miscellaneous Type Facilities”), as amended, or (b) industrial process water flow as quantified by determining the cubic feet per second released during the average of seven consecutive 24-hour periods.

   Best Management Practice (BMP). A measure approved by the commissioner and used to control the adverse stormwater-related effects of development.

   Building commissioner. The commissioner of buildings or his designee.

   Commissioner. The commissioner of water management or his designee.

   Developer. Any person who manages, organizes, oversees, plans or supervises the creation of a Regulated Development.

   Drainage Area. Any location from which or through which stormwater moves to a drainage system.

   Existing Conditions. The condition of a site in the ten years prior to the date of a Plan submission, as shown on historical aerial photographs or other verifiable documentation. If a site has been demolished and/or cleared within such ten-year period, its conditions prior to such demolition and/or clearing may be used as a basis for existing conditions.

   Impervious Surface. A surface which substantially precludes the infiltration of water, such as concrete, asphalt, tile or compacted gravel.

   Infiltration. The passage, movement or percolation of water into and through soil surfaces, including soil surfaces on roofs and in landscaped areas.

   Owner. The owner, manager, agent or other person in charge, possession or control of a Regulated Development or any part thereof.

   Plan. The Stormwater Management Plan required by this chapter.

   Regulated Development or Development. Any construction activity, excavation or grading, commencing on or after January 1, 2008, that:

      (a)   disturbs a land area or substantially contiguous land areas of 15,000 or more square feet in the aggregate. Land areas separated by public right-of- way at the conclusion of development shall not be deemed “substantially contiguous” to each other for purposes of this definition. For purposes of calculating square footage pursuant to this paragraph (a), “land area” shall include twenty-five percent of the square footage of the sidewalls of a building that directly connects to the sewer system via side gutters, and shall also include any average dry-weather flow based on a conversion rate of 1.0 cfs (cubic feet per second) into one acre (43,560 square feet), or

      (b)   creates an at-grade impervious surface of 7,500 or more substantially contiguous square feet, or

      (c)   results in any discharges of stormwater into any waters or separate sewer system.

   For purposes of this definition, square footage shall be calculated based upon the project as a whole, regardless of whether construction proceeds in phases. A Regulated Development shall not include projects located entirely within the public right-of-way at the conclusion of development. With respect to a project located both on the public right-of-way and on private property at the conclusion of development, that portion of the project located on the public right-of-way will not be included in calculating the square footage thresholds of subparagraphs (a) and (b) of this definition. If a project includes Residential Development, the Residential Development will not be included in calculating the square footage thresholds of subparagraphs (a) and (b) of this definition.

   Residential Development. A Regulated Development, or portion thereof, which upon completion will result in the subdivision of land into detached single-family or two-family dwellings.

   Runoff. The water derived from precipitation falling onto a Regulated Development which is in excess of the infiltration capacity of the soils of that Development, which flows over the surface of the ground or is collected in any watercourse.

   Stormwater. Water derived from any form of precipitation.

   Stormwater Drainage System. Any and all natural and artificial means used in combination to conduct stormwater to, through, or from a Drainage Area to the point of infiltration or final outlet from a Regulated Development. A Stormwater Drainage System includes, but is not limited to, any of the following: conduits and appurtenance features, canals, channels, ditches, streams, culverts, streets, storm sewers, detention basins, swales, vegetated areas and pumping stations.

   Stormwater Management Plan. A detailed formulation of a program of action which describes a proposed or existing Stormwater Drainage System and environmental features applicable to a Regulated Development. The Plan shall include programs for grading and drainage, operations and maintenance, and soil, sediment and erosion control. These programs shall consist of written documentation, scaled maps and drawings with supporting engineering calculations.

   Watercourse. Any channel, natural or artificial, lined or unlined, through which water flows or may flow.

   Waters. All watercourses and all lakes, ponds, wetlands and other bodies of water, whether natural or artificial, that are located wholly or partly within or adjoining the territorial boundaries of the City.

(Added Coun. J. 12-13-06, p. 95586, § 1; Amend Coun. J. 11-8-12, p. 38872, § 208)

11-18-030 Stormwater management plan – Required.

   Every Regulated Development shall at all times have in place a Plan approved by the City. In addition to such other requirements as the commissioner may set forth by regulation, the Plan shall include the following:

   (a)   Provisions for Stormwater Management:

      (1)   Rate Control. Stormwater Drainage Systems shall manage the peak rate of discharge from the Regulated Development, incorporating the maximum permissible release rate. Provided, however, that Developments that create an at-grade impervious surface of less than 7,500 substantially contiguous square feet and that directly discharge to waters shall not be subject to the rate control requirements of this subparagraph (a)(1).

      (2)   Volume Control. Stormwater drainage systems shall reduce the volume of runoff from a Regulated Development by one of the following measures:

         (A)   capture one-half inch of runoff from all impervious surfaces in accordance with volume control BMPs; or

         (B)   for Developments that do not directly discharge to waters or to a municipal separate storm sewer system, achieve a fifteen percent reduction in impervious surfaces from existing conditions.

   (b)   Provisions for sediment and erosion control.

   (c)   Provisions for operations and maintenance.

(Added Coun. J. 12-13-06, p. 95586, § 1)

11-18-040 Stormwater management plan – Exceptions.

   (a)   A Plan shall not be required for Residential Development.

   (b)   The volume control requirements of a Plan shall not apply to the following:

      (1)   Developments that do not directly discharge to waters or to a municipal separate storm sewer system and that will upon completion of development have less than fifteen percent impervious surfaces.

      (2)   Developments consisting of surfaces at an airport that are intended for aircraft operation.

      (3)   Developments taking place at any facility that is operating under a permit issued pursuant to the National Pollution Discharge Elimination System, 40 C.F.R. Part 122, as amended, for industrial or municipal discharges.

(Added Coun. J. 12-13-06, p. 95586, § 1)

11-18-050 Stormwater management plan – Submission, approval and compliance.

   (a)   The submission of the Plan required by this chapter shall be made by the Applicant to the building commissioner in such form(s) and format(s) as the commissioner may require. As part of the Plan submission, the Applicant shall provide such information regarding the site and its proposed uses as the application may require. The Plan submission shall be submitted as part of the sewer permit review process required by Chapter 11-16 of the Code. The building commissioner shall be the custodian of all such submissions.

   (b)   The Plan shall be valid only upon approval by the building commissioner.

   (c)   Before a Plan may be approved, the Applicant must certify to the building commissioner that the Applicant has met or will meet, in addition to the requirements of this chapter, all other city, county, state, and federal requirements related to floodplains, wetlands and water quality.

   (d)   Following Plan approval and completion of construction, the Owner shall provide to the building commissioner, in such time frame as established by regulation, as-built drawings of the Development in such form(s) and format(s) as the commissioner of water management may require. Consistent with applicable law, the building commissioner shall treat such as-built drawings as confidential trade secrets, and shall provide the Owner with a copy of any appeal, received by the building commissioner, of the building commissioner's notice of denial provided to a third party seeking inspection and copies of such drawings.

(Added Coun. J. 12-13-06, p. 95586, § 1; Amend Coun. J. 11-8-12, p. 38872, § 209)

11-18-060 Stormwater management plan – Amendment.

   A Regulated Development shall be developed, operated and maintained in compliance with its approved Plan until such time as the City approves an amendment or other modification of the Plan for that Regulated Development. The submission of a request for amendment shall be made to the building commissioner in such form(s) and format(s) as the commissioner of water management may require. The building commissioner shall review any request for amendment and shall notify the Applicant of the result of such review. An amendment may only be granted if the building commissioner determines that the amendment will not have a detrimental effect on the Plan.

(Added Coun. J. 12-13-06, p. 95586, § 1; Amend Coun. J. 11-8-12, p. 38872, § 210)

11-18-070 Change of ownership.

   (a)   Upon a change of ownership of a Regulated Development, each new Owner of the Regulated Development or any part thereof shall comply with the Plan approved for that Regulated Development until such time as the building commissioner approves an amendment or other modification of the Plan for that Development.

   (b)   A change of ownership of a Regulated Development shall not be considered to be an amendment. However, the Owner of a Regulated Development for which a Plan is required or has been approved shall notify each new Owner of the applicability of the Plan to the Regulated Development, and provide each new Owner with a copy of the Plan, before consummation of the sale of the Development. A violation of this subsection (b) shall be punishable by a fine of $500.00.

(Added Coun. J. 12-13-06, p. 95586, § 1; Amend Coun. J. 11-8-12, p. 38872, § 211)

11-18-080 Stormwater management plan – Fees.

   A non-refundable fee for review of a Plan submission or variance request shall be remitted to the building commissioner as part of the Plan submission or variance request. The fee for review of a Plan submission, or variance request based upon Section 11-18-090(b)(2), (3) or (4), shall be as follows:

   (a)   For Regulated Developments affecting less than 50,000 square feet – $1,000.00.

   (b)   For Regulated Developments affecting 50,000 or more square feet – $3,000.00.

   The fee for review of a variance request based upon Section 11-18-090(b)(1) shall be 50% greater than the amounts specified in (a) and (b) above.

   (c)   For amendments to a Plan submitted within one year of Plan approval, the fee shall be $350.00 per submission. For amendments submitted over one year after Plan approval, the fee shall be $500.00 per submission.

(Added Coun. J. 12-13-06, p. 95586, § 1; Amend Coun. J. 11-8-12, p. 38872, § 212)

11-18-090 Variance.

   (a)   Upon written petition of the Applicant demonstrating that exceptional circumstances exist, the commissioner may grant a variance, in whole or in part, from the requirements of Section 11-18-030. To the extent that the Applicant can comply with Section 11-18-030, the Applicant must do so.

   (b)   Exceptional circumstances justifying the application of this section shall exist only where the Applicant can clearly demonstrate, to the satisfaction of the commissioner, that one of the following four circumstances exists:

      (1)   The Applicant cannot comply with Section 11-18-030 because of the site's exceptional physical conditions or circumstances. To demonstrate that such conditions or circumstances exist, the Applicant must provide supporting documentation. At a minimum, the Applicant must show that the site is designed to minimize the peak rate of discharge and volume of stormwater from the Development. Such showing must include a BMP feasibility evaluation for each building, parking area, landscaped area and each other significant footprint at the site. The evaluation must include all necessary technical computations and analyses (examples include engineering, architectural and horticultural analyses) to assess fully the applicability of pertinent BMPs and the extent to which they can be applied to comply with Section 11-18-030.

      (2)   The Applicant cannot comply with Section 11-18-030 without causing a public nuisance.

      (3)   The Applicant cannot comply with Section 11-18-030 without violating the Building Code or the Fire Code, as those terms are defined in Section 1-4-090 of the code, or a state or federal law.

      (4)   The Regulated Development is a registered landmark and compliance with Section 11-18-030 would violate the Regulated Development's landmark status.

   (c)   Applications for a variance shall be in a form prescribed by the commissioner. All applications for a variance shall bear the notarized signature and certification of a professional architect, engineer or geologist licensed in the State of Illinois.

   (d)   In applying for a variance, an Applicant may propose, and the commissioner may consider, alternative measures to accomplish the stormwater management goals of this chapter.

(Added Coun. J. 12-13-06, p. 95586, § 1)

11-18-100 Site inspections.

   To enable the commissioner, or his designee, to monitor compliance with this chapter, the Owner shall permit access during reasonable hours to those areas of a Regulated Development affected by the Plan.

(Added Coun. J. 12-13-06, p. 95586, § 1; Amend Coun. J. 11-16-11, p. 13798, Art. II, § 6)