Stormwater Quality Design Manual (May 2007) - City of Sacramento ...

Technical RequirementsSand FilterTable SF-4. Design Data Summary Sheet for Sand FilterDesigner:Company:Project:Location:Date:1. Determine Design Water Quality Volumea. Tributary drainage areab. Water Quality Volume (based on 48 h drawdown)Area = ft 2WQV = ft 32. Sedimentation Basin Volume (V sb ≥ WQV) V sb = ft 33. Sedimentation Basin Depth (3 ft ≤ d sb ≤ 10 ft) d sb = ft4. Sedimentation Basin Area (A sb = V sb / d sb ) A sb = ft 25. Sedimentation Basin Shapea. Sedimentation Basin Length (L sb )b. Sedimentation Basin Width (W sb )c. Sedimentation Basin L:W Ratio (2:1 minimum)L sb =W sb =L:W =ftft6. Filtration Basin Storage Volume (V fbs ≥ 0.2 x WQV) V fbs = ft 37. Filter Bed Surface Areaa. Minimum filter surface area for storage (A fbs )A fbs = V fbs / d fbsA fbs = ft 2where d fbs = Depth of storage above filter bed (3 ft min.)b. Minimum filter surface area for flow (A ff )Sand Bed Depth (d f ≥ 1.5 ft)Coefficient of permeability for sand (k = 0.146 ft/h)Time required pass through filter (t f = 40 h)d fbs =d f =k =t f =ftftft/hrhrAff(WQV)( df)=(k)(d + d )(tfbsc. Final design filter bed surface area (A fb )ff)A ff = ft 2A fb = ft 28. Filter Bed Design (Check Type Used) Sand Bed with Gravel Underdrain Sand Bed with Trench UnderdrainStormwater Quality Design Manual for the Sacramento and South Placer RegionsSF-12 May 2007