BMP selection based on physical feasibility BMP selection based on physical feasibility

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 ft2	5 acre maximum; 0.5-2.0 acre preferred	Any soil; use underdrain for C and D soilsd		3 feet	3 feet	20%	Yes
Filtration - media	Negligible, 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 depth	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%	10 to 25 acres recommendedb	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 or less 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