The City has calculated the average Impervious Surface of Single-Family Residential Properties within the City to be 3,431 square feet. For purposes of calculating Storm drainage service charges under this Chapter, one (1) Equivalent Residential Unit (ERU) shall be equal to 4,020 square feet of Impervious Surface. Each Single-Family Residential Property within the City shall be assigned one (1) ERU. The total number of ERUs of each Non-Residential Property within the City (as defined in Section 929.03 hereof) shall be calculated by determining the total square footage of Impervious Surface on each such Property and dividing this total by 4,020. In no case shall any Non-Residential Property have an ERU of less than one (1). The total square footage of Impervious Surface shall be measured by the City based on the records of the County Recorder or Auditor, the City, or through field examination or photogrammetric analysis; provided, however, that owners of Properties which are proposed for subdivision and/or development after the date of the adoption of this Chapter shall include on all preliminary plan and final plan drawings submitted to the City in connection with the subdivision approval process, a certification as to the total square footage of Impervious Surface to be located on the Property upon its development. (Ord. 35-05. Passed 9-19-05.)