The volume of storm water discharge used for calculating all user charges shall be based upon the Equivalent Residential Unit.
(a) Single-Family Residential - The volume of storm water discharge shall be determined by a survey of impervious area of such structures representing neighborhoods throughout the Village. Impervious areas to be calculated shall include, but not be limited to, roofs, walkways, patios, driveways, and parking areas.
Upon calculation of the impervious area square footage, an average shall be determined. This averaged square footage shall be applied to all single-family residential properties, and shall represent an Equivalent Residential Unit (ERU). For example one ERU = xxx square feet.
(b) Multi-Family Residential - The volume of storm water discharge shall be determined by applying the ERU to each residential unit where each unit is billed for utilities separately, or where the units are billed jointly, by dividing the total impervious area of the residential property, as surveyed and calculated by village personnel or its designee, by the ERU to determine the number of ERU's (volume) discharged into the public storm drainage system.
(c) Commercial, Industrial, and Institutional or other Public User - The volume of storm water discharge shall be determined by a survey of the subject property by village personnel or its designee and a calculation of the impervious area shall be made. The total impervious area square footage shall be divided by the Equivalent Residential Unit (ERU) to determine the number of ERU's (volume) discharged into the public storm drainage system.
(d) Vacant Structures - The volume of storm water discharge shall be determined by one of the above methods for all vacant property based upon its most recent use.
(e) Detention ponds, which detain discharge of storm water into the public storm drainage system, shall not reduce the calculation of impervious area.
(f) Retention ponds, which do not discharge into the public storm drainage system, shall cause a reduction in the calculation of impervious area proportionate to that area which drains to said retention pond. This reduction shall be at the sole discretion of the Planning Commission, upon recommendation of the Engineer.
(g) Property surveys and calculation of impervious areas shall be the responsibility of the Codes Enforcement Officer or Engineer as directed by the Planning Commission.
(h) Final determination for the method and manner of storm water discharge volume shall be the responsibility of the Planning Commission, upon recommendation by and input from the Engineer.
(Ord. 38-97. Passed 10-20-97)