(a) All storm water runoff generated from a site shall be adequately treated before discharge in order to ensure maximum pollutant removal is achieved to the extent where these discharges shall not cause or contribute to violations of the water quality standards. It will be presumed that a storm water management system complies with this requirement if:
(1) The preferred method is to design water quality BMPs to trap 85% of total suspended solids (TSS) based on annual loadings by particle class. An alternative method as a default criterion is to design BMPs, to capture the first inch of runoff from the impervious area of the site and discharge it over a 24-hour period.
(2) The Director has discretion to require more stringent controls for water quality where the Director determines the minimum standards of this section are not adequate. Areas where more stringent controls may apply include outstanding resource waters, trout waters, wetlands, steep slopes, 303(d) listed waters, TMDLs or other sensitive areas.
(b) All development and redevelopment projects and portions of redevelopment projects disturbing 1 acre or more or that will result in more than 1 cubic foot per second increase in peak runoff rates shall meet the requirements of this section even though there is not a change in land use.
(Ord. 4281, passed 5-5-2009; Ord. 4698, passed 5-5-2015)