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− | + | <font size=3>'''This table shows guidance on BMP selection based on physical feasibility characteristics of a site.'''</font size><br> | |
− | Link to this [[BMP selection based on physical feasibility|table]]. | + | Link to this [[BMP selection based on physical feasibility|table]]. |
<table class="sortable"><tr> | <table class="sortable"><tr> | ||
<th>BMP group</th> | <th>BMP group</th> |
This table shows guidance on BMP selection based on physical feasibility characteristics of a site.
Link to this table.
BMP group | Surface areaa | Drainage area | Soil infiltration rate | Head | Separation from bedrock | Depth to seasonally high water table | Maximum slopec | Ultra-urban |
---|---|---|---|---|---|---|---|---|
Bioretention | 7-10%; Minimum 200 ftb2 | 5 acre maximum; 0.5-2.0 acre preferred | Any soil; use underdrain for C and D soilsd | 4-6 feet | 3 feet | 3 feet | 20% | Yes |
Filtration - media | Neglibible, except for access | 5 acre maximum; 0.5-2.0 acre preferred | Media part of designd | 2-6 feet | 0 feet if enclosed | 3 feet for vegetated; 0 feet if enclosed | 20% | Yes |
Filtration - vegetative | Varies based on depth | 10 acre maximum | Media part of design | 2-6 feet | 0 feet if enclosed | 3 feet for vegetated; 0 feet if enclosed | 20% | Possible |
Infiltration trench | Varies based on depth | 5 to 10 acre maximum | Native soils with i>=0.2 inches/hour | 2-12 feet | 3 feet | 3 feet | 15% | Possible |
Infiltration basin | Varies based on dept | 5 to 50 acre maximum | Native soils with i>=0.2 inches/hour | 2-12 feet | 3 feet | 3 feet | 15% | No |
Stormwater ponds | 1-3% | 25 acre minimumb | A or B soils may require liner | 3-10 feet | 0 feet (shallow soil limits design) | 0 feet (except if hotspot or aquifer) | 25% | No |
Constructed wetlands | 2-4% | 25 acre minimumb | A or B soils may require liner | 3-10 feet | 0 feet | 0 feet (except if hotspot or aquifer) | 25% | No |
aSurface area as a function of contributing surface area, except for ponds and wetlands, where it is a function of entire drainage area
b10 acres may be feasible if groundwater is intercepted and/or if water balance calculations indicate a wet pool can be sustained
cSlope is defined as the slope across the proposed location of the practice
dInfiltration gallery could be designed to provide limited recharge