Filtration tables combined Filtration tables combined

Filtration - pollutant removal information

Filtration - pollutant removal information
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Device	Primary mechanism	Secondary mechanism	Other mechanism	Proprietray/nonproprietray	Above ground/below grade	Pollutants removed
Pretreatment vegetated filter strip (VFS)	Filtration	Screening/Straining	Settling	Nonproprietary	Above Ground	Sediment, organic matter, trace metals, nutrients, pesticides
Level-Spreader - Vegetative Filter Strip System (LS-VFS)	Filtration	Screening/Straining	Settling	Nonproprietary	Above Ground	Sediment, organic matter, trace metals, nutrients, pesticides [1]
Up-Flo Filter by Hydro International	Filtration	Settling	Screening/Straining	Proprietary	Underground	Sediment, heavy metals, oil, nutrients, floatables, trash [2]
Storm Clean R catch basin filtration insert by CleanWay	Filtration	Screening/Straining		Proprietary	Underground	Trash and debris, sediment and total suspended solids, and oil (hydrocarbons and heavy metals depending on filter element options - Vermiculite media and MetalZorb media respectively) [3]
The StormBasin TM	Filtration			Proprietary	Underground	Sediment, trash, vegetation, nutrients, bacteria, oil, metals [4]
Gravel filtration (e.g.,Filter socks, Rock Sox, gravel bags, gravel filter booms, etc.)	Filtration	Screening/Straining		Proprietary and Nonproprietary	Above Ground	Sediment, trash, organic matter
Filtration berm	Filtration			Nonproprietary	Above Ground	Sediment, trash, nutrients
SiltSoxx R by Filtrexx	Filtration	Screening/Straining		Proprietary	Above Ground	Sediment, hydrocarbons, nutrients [5]
StormExx R by Filtrexx	Filtration	Screening/Straining		Proprietary	Underground	Sediment, bacteria, heavy metals, hydrocarbons, nutrients

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% [6]; [7]	<1 ft/s, flow should be sheet flow and unconcentrated [8]	Maximum 72 hours [9]	VFS width (parallel to sheet flow) = 25-100 ft depending on vegetation, slope and drainage area soil [10]; [11]	Soil, grass [12]	Residential lawns, parking lots, part of riparian buffer [13]	Hydrologic Soil Groups A-D permitted, table for corresponding slopes [14]
Level-Spreader - Vegetative Filter Strip System (LS-VFS)	< a few acres [15]	<=10cfs [16]	Maximum 72 hours [17]	LS width (parallel to sheet flow) = 10-100 ft, VFS width >= 30-50 ft [18]	Concrete, soil, grass [19]	Distance from surface waters: LS and VFS must be outside riparian buffer, LS must be outside stormwater setbacks [20]	VFS max slope = 8% [21]
Up-Flo Filter	0.66 acres impervious drainage area per filter module based on Nashville design storm [22]	0.056 cfs per filter module (max number of modules 6-54) [23]		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 [24]
Storm Clean		Filtration flow rates (nominal/max)= 40/80 gpm, Strainer flow rate >= 100 gpm [25]		Filtration surface area (fabric elements) = 6.4 sq ft, Strainer surface area = 4.8 sq ft [26]	Stainless steel [27]	Can be fit into existing catch basin, curb inlet, drop inlet, or downspout [28]
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. [29]	Bags are high quality woven polymer material with high UV rating, gravel [30]	In front of or around existing catch basin inlets [31]
Filtration berm		1 cfs per 8 linear ft [32]		Berm height = 12-18 inches high with 3:1 side slopes, every 100-300 feet depending on slope [33]	Washed, well-graded gravel/rock ¾ to 3 inches in size with <5% fines [34]	Right-of-ways, traffic areas, construction sites [35]	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 [36]; [37]	Filtrexx Media in Filtrexx Mesh [38]	Existing inlets, site perimeters, paved surfaces, compacted soils, exposed slopes [39]	Compacted or susceptible to erosion
StormExx R by Filtrexx	Same as catch basin	15-40 gpm [40]		15-gallon storage, fits any existing storm drain [41]	Stainless steel or HDPE, EnviroSoxx filtering media cartridge [42]	Existing inlet

Filtration - system and component sizing

Filtration - system and component sizing
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Device	Land use	Downstream BMP (type)	Enhancement opportunity	Sizing calculations	Inlets/oulets	Flow diversion structures	Slopes
Pretreatment vegetated filter strip (VFS)	Often not suitable for in ultra-urban settings where space is limited or areas with high pollutant loading [43]	Infiltration, Retention [44]	No	Depends on slope and imperviousness of drainage area: See MPCA table entitled “Guidelines for filter strip pre-treatment sizing”	Outflow 2-3 inches above filter strip [45]	May include pervious berm or check dam, which should have an outlet pipe or overflow weir [46]	2-6% depending on soil, 0% perpendicular to flow [47]
Level-Spreader - Vegetative Filter Strip System (LS-VFS)	Often not suitable for in ultra-urban settings where space is limited or areas with high pollutant loading [48]	Infiltration, Retention [49]	No	LS length: 10 ft/cfs, VFS sized for a 1 in/hr storm (larger flows bypassed)	Outflow 2-3 inches above filter strip [50]	May include flow bypass, forebay and/or blind swale, and underdrain [51]	Depth at inlet = 3 ft, depth before outlet = 1 ft
Up-Flo Filter	Suited to industrial sites, locations contributing to wetlands/protected regions or area requiring high level of treatment [52]		Yes	See manufacturer’s sizing tool (requires registration)	Can accept 15 in or 24 in pipes [53]	Bypass siphon, sump, filter module, outlet module [54]
Storm Clean		Underground Injection Controls (UIC), swales, detention/ retention ponds, infiltration trenches [55]	Yes	Sized to rectangular or round catch basin, adaptive design available for larger catch basins [56]; [57]; [58]		Bypass port, strainer, filter element [59]
Gravel filtration	Areas with high erosion concern such as construction sites.		No	Each gravel bag can be adjusted to meet specific flow, sediment, or filtration requirements. [60]
Filtration berm	Residential, Commercial, Industrial, Retrofit, Highway/Road, limited Ultra-Urban [61]		No	8 linear feet per 1 cfs based on 10-yr, 24-hr design storm [62]	Size outlets for 24-hour drawdown time [63]		Suitable for most steep surface slopes [64]
SiltSoxx R by Filtrexx	Construction, Residential, Commercial	No restriction	Yes	Flow-based, see time to overflow at different flow rates (1-7.5 gpm/linear ft) for each size in Table 1			Slope up to 1:1 grade [65]
StormExx		No restriction	Yes	One-size fits all with modification supports [66]	Treated water outlet from cartridge = 2 in diameter	Bypass structure

Filtration - installation and maintenance recommendations

Filtration - installation and maintenance recommendations
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Device	Installation notes	Frequency of inspections	Maintenance checklist (link)	Permitted on private land/ Maintenance agreement recommended	Practices for minimizing sediment and trash buildup	Practices for minimizing washout	Cost considerations (equipment needed and man hours)
Pretreatment vegetated filter strip (VFS	Construction sequence	Quarterly and after every 1 in storm event for first two years, then biannually [67]			Sediment removed at least biannually of when buildup exceeds 2 inches in depth [68]	Appropriate vegetation and landscaping maintenance; See Appendix [69]	Generally $100-$1400 per acre [70]
Level-Spreader - Vegetative Filter Strip System (LS-VFS)	Construction notes	Quarterly and after every 1 in storm event for first two years, then biannually [71]			Sediment removed at least biannually of when buildup exceeds 2 inches in depth [72]	Appropriate vegetation and landscaping maintenance; See Appendix [73]	Generally $100-$1400 per acre [74]
Up-Flo Filter		Every 6 months for first year of operation, then site specific. Floatables, sediment, media, and drain down filter each need to be inspected [75]	Inspection and maintenance checklist		Sediment removal at least once per year or once sediment depth is 16 inches [76]		Routine maintenance for manhole unit takes about 1 hour [77]
Storm Clean	One-person installation [78]	Monthly [79]	Maintenance instructions		When visual inspection or water sampling show degradation. MetalZorb is non-hazardous and does not require special waste handling [80]		Vactor truck or large shop vac; One person [81]
Gravel filtration		After each rainfall			Remove sediment from behind bag as needed
Filtration berm	Construction sequence	After each rainfall [82]	Maintenance considerations		Routinely remove accumulated trash and debris [83]	Appropriate vegetation and landscaping maintenance (eg. mowing and level gradient restoration); See Appendix [84]	Depends on height, length, width, and location of berm [85]
SiltSoxx R by Filtrexx	Installation instructions	Within 24 hours after rainfall event [86]	Maintenance instructions		Sediment removal from upslope side when accumulation has reached ½ the effective height of the Soxx [87]
StormExx	Installation notes	Every 90 days, frequent drive through inspection during leaf-fall and after storm events [88]		Costs for one year of service and maintenance may be added to proposal [89]	Quarterly general service, fall cleaning and cartridge replacement [90]