Filtration - system design information

Filtration - system design information
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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. [17]	Bags are high quality woven polymer material with high UV rating, gravel [18]	In front of or around existing catch basin inlets [19]
Filtration berm		1 cfs per 8 linear ft [20]		Berm height = 12-18 inches high with 3:1 side slopes, every 100-300 feet depending on slope [21]	Washed, well-graded gravel/rock ¾ to 3 inches in size with <5% fines [22]	Right-of-ways, traffic areas, construction sites [23]	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 [24]; [25]	Filtrexx Media in Filtrexx Mesh [26]	Existing inlets, site perimeters, paved surfaces, compacted soils, exposed slopes [27]	Compacted or susceptible to erosion
StormExx R by Filtrexx	Same as catch basin	15-40 gpm [28]		15-gallon storage, fits any existing storm drain [29]	Stainless steel or HDPE, EnviroSoxx filtering media cartridge [30]	Existing inlet