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]

This page was last edited on 13 April 2020, at 18:00.

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