Unless granted a waiver or variance by the Director of Public Works, the following performance criteria shall be addressed for stormwater management at all sites:
(A) All site designs shall control the peak flow rates of stormwater discharge associated with design storms specified in this chapter or in the city’s LDRs or state regulations, and reduce the generation of post construction stormwater runoff rates to pre-construction levels. These practices should seek to utilize pervious areas for stormwater treatment and to infiltrate stormwater runoff from driveways, sidewalks, rooftops, parking lots, and landscaped areas to the maximum extent practical to provide treatment for both water quality and quantity. Low-impact development (LID) is encouraged.
(B) To protect stream channels from degradation, specific channel protection criteria as prescribed in the city’s LDRs shall be met.
(C) Stormwater discharges to critical areas with sensitive resources (i.e., cold water fisheries, swimming beaches, recharge areas, water supply reservoirs) may be subject to additional performance criteria, or may need to utilize or restrict certain stormwater management practices.
(D) Stormwater that discharges from hotspots may require the application of specific structural BMPs and pollution prevention practices.
(E) For construction projects that disturb 25 acres or more and discharge the pollutant or pollutants of concern to a water on the South Carolina 303(d) List of Impaired Waters, the stormwater pollution prevention plan (SWPPP) prepared by the applicant must contain a written quantitative and qualitative assessment showing that the BMPs selected will control the construction and post construction stormwater discharges so that the stormwater discharges will not cause or contribute to a violation of water quality standards. A copy of the most current 303(d) List of Impaired Waters can be downloaded at the following DHEC Website: www.sedhec.gov/water/html/tmdl.html.
(F) All site designs are required to show appropriate erosion and sediment control BMPs accompanied by design calculations to support chosen controls.
(G) All site designs are required to exhibit control of waste such as discarded building materials, concrete truck washout, chemicals, litter, and sanitary waste at the construction site that may cause adverse impacts to water quality.
(Ord. 2008-06, passed 4-14-08) Penalty, see § 52.999