Filtration - system design information
Link to this table

Device Drainage area Entrance/exit velocity Drain down/detention time Dimensions Materials Layout Recommendations (physical location, off-line placement) Soils
Pretreatment vegetated filter strip (VFS) < a few acres, max flow path 75-150 ft depending on perviousness, slope of drainage area <5% [1]; [2] <1 ft/s, flow should be sheet flow and unconcentrated [3] Maximum 72 hours [4] VFS width (parallel to sheet flow) = 25-100 ft depending on vegetation, slope and drainage area soil [5]; [6] Soil, grass [7] Residential lawns, parking lots, part of riparian buffer [8] Hydrologic Soil Groups A-D permitted, table for corresponding slopes [9]
Level-Spreader - Vegetative Filter Strip System (LS-VFS) < a few acres [10] <=10cfs [11] Maximum 72 hours [12] LS width (parallel to sheet flow) = 10-100 ft, VFS width >= 30-50 ft [13] Concrete, soil, grass [14] Distance from surface waters: LS and VFS must be outside riparian buffer, LS must be outside stormwater setbacks [15] VFS max slope = 8% [16]
Up-Flo Filter 0.66 acres impervious drainage area per filter module based on Nashville design storm 0.056 cfs per filter module (max number of modules 6-54) Round manhole: 4 ft diameter, 7.5 ft high Rectangular vaults: 6 ft x 8 ft x 6.5 ft to 15 ft x 13 ft x 6.5 ft Roads, carparks, commercial properties, airports, offline and online treatment of existing storm drains
Storm Clean Filtration flow rates (nominal/max)= 40/80 gpm, Strainer flow rate >= 100 gpm Filtration surface area (fabric elements) = 6.4 sq ft, Strainer surface area = 4.8 sq ft Stainless steel Can be fit into existing catch basin, curb inlet, drop inlet, or downspout
Gravel filtration Same as inlet gravel bags are placed around Varies by need. For example, one version available comes in 11x48, 11x96, and 19x28 inch bags Bags are high quality woven polymer material with high UV rating, gravel In front of or around existing catch basin inlets
Filtration berm 1 cfs per 8 linear ft Berm height = 12-18 inches high with 3:1 side slopes, every 100-300 feet depending on slope Washed, well-graded gravel/rock ¾ to 3 inches in size with <5% fines Right-of-ways, traffic areas, construction sites No restriction
SiltSoxx R by Filtrexx Varies by application Varies by application Available in 5 in to 32 in diameter depending on application, up to 200 ft in length Filtrexx Media in Filtrexx Mesh Existing inlets, site perimeters, paved surfaces, compacted soils, exposed slopes Compacted or susceptible to erosion
Shorex R by Filtrexx Same as catch basin 15-40 gpm 15-gallon storage, fits any existing storm drain Stainless steel or HDPE, EnviroSoxx filtering media cartridge Existing inlet

This page was last edited on 3 August 2022, at 19:05.