(c) The standards in EC 9.6792(3) do not apply to land use applications or development <br />permit applications within the S-DR Downtown Riverfront Special Area Zone. Instead, the <br />standards at EC 9.3155(17) apply. <br />(3) Standards. <br />(a) Stormwater quality facilities for water quality treatment shall be selected from and sited, <br />designed, and constructed according to the Stormwater Management Manual. The selected <br />stormwater quality facilities shall treat all stormwater runoff from all new or replaced <br />impervious surface areas, or an equivalent on -site area, that will result from the water quality <br />design storm. <br />(b) Stormwater quality facilities shall be selected based on the following priority order. <br />1. Infiltration shall be utilized for treatment of the water quality design storm runoff unless <br />one of the following site conditions exists: <br />a. Infiltration rates are less than 2 inches per hour; <br />b. Bedrock is less than 5 feet below the ground surface; <br />c. Groundwater elevations are less than 6 feet below the ground surface; or <br />d. Ground surface slopes are greater than 10%. <br />2. If any of the site conditions listed in subsection (3)(b)1 exist, extended filtration <br />(filtration through natural or engineered media) shall be utilized to treat the water quality <br />design storm runoff from the impervious surface areas unless: <br />a. The applicant submits a report that includes a site plan of the proposed <br />development and the required sizing of the stormwater quality facility based upon the <br />water quality design storm requirement showing that the development site has <br />insufficient land area to construct an infiltration or extended filtration facility to treat <br />the water quality design storm runoff without reducing the size of the proposed <br />development; and <br />b. The proposed development is otherwise consistent with all other applicable lot <br />and development standards. <br />(c) An applicant that is not required to use an infiltration or filtration system for any of the <br />reasons stated in (b) or (d) of this section will be subject to the Low Impact Development <br />component of the City's system development charge improvement fee due to the reliance on <br />an off -site system. In that case, the City's system development charge methodologies may <br />include a stormwater system development charge credit for an approved on -site mechanical <br />treatment facility. <br />Ordinance -- Page 3 of 7 <br />