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EXHIBIT A: CHAPTER 928 <br />to infiltrate the water quality volume or reduce the temperature of <br />discharged runoff. SCMs that reduce the temperature of discharged runoff <br />include bioretention, permeable pavement, underground detention, and <br />incorporation of shading and infiltration in parking lot design. <br />Each practice shall be designed to facilitate sediment removal, vegetation <br />management, debris control, and other maintenance activities defined in <br />the Inspection Plan and Maintenance Agreement for the site. <br />Table 2: Draw Down Times for Stormwater Control Measures <br />Stormwater Control Measure <br />Drain Time of WQv <br />Infiltration Basin or Trench' <br />48 hours <br />Permeable Pavement — Infiltration' <br />48 hours <br />Permeable Pavement — Extended Detention <br />24 hours <br />Extended Detention Facilities <br />■ Dry Extended Detention Basin' <br />48 hours <br />■ Wet Extended Detention Basins <br />24 hours <br />■ Constructed Wetlands (above permanent pool) 4 <br />24 hours <br />■ Bioretention Area/Cell'�' <br />24 hours <br />■ Sand and other Media Filtration' <br />24 hours <br />■ Pocket Wetland' <br />24 hours <br />Practices designed to fully infiltrate the WQ, shall empty within 48 hours to provide storage for subsequent <br />storm events. <br />Z The use of a forebay and micropool is required on all dry extended detention basins. Each is to be sized at a <br />minimum 10% of the WQ�. <br />3Provide both a permanent pool and an extended detention volume above the permanent pool. each sized with <br />at least 0.75*WQv. <br />'Extended detention shall be provided for the WQv above the permanent water pool. <br />s The surface ponding area shall completely empty within 24 hours so that there is no standing water. Shorter <br />drawdown times are acceptable as long as design criteria in Rainwater and Land Development have been met. <br />6 This includes grassed linear bioretention, which was previously titled enhanced water quality Swale. <br />Pocket wetlands must have a wet pool equal to the WQ,., with 25% of the WQ, in a pool and 75% in marshes. <br />The ED, above the permanent pooI must beequal to the WQ,. <br />Additional criteria apple to infiltration facilities: <br />a. Infiltration facilities should be designed to meet all criteria in Rainwater <br />and Land Development. <br />b. All runoff directed into an infiltration basin must first flow through a <br />pretreatment practice such as a grass channel or filter strip to remove <br />coarser sediments that could cause a loss of infiltration capacity. <br />C. During construction, all runoff from disturbed areas of the site shall be <br />diverted away from the proposed infiltration basin site. No construction <br />equipment shall be allowed within the infiltration basin site to avoid soil <br />compaction. <br />4. Additional criteria for extended detention facilities: <br />a. The outlet shall be designed to not release more than the first half of the <br />water quality volume in less than 1 /3rd of the drain time. The outlet shall <br />be designed to minimize clogging, vandalism, maintenance, and promote <br />