Considerations for structural BMP use in karst settings.
Link to this table
| BMP |
Karst considerations |
| Bioretention |
If containment levels remain high after treatment or if water inflow presents a threat, an underdrain and-or use of a synthetic or other impermeable membrane liner should be considered to seal the bottom of the system. |
| Media filter |
If containment levels remain high after treatment or if water inflow presents a threat, an underdrain and-or use of a synthetic or other impermeable membrane liner should be considered to seal the bottom of the system. |
| Vegetative filter |
- Avoid water ponding
- Should be engineered to avoid channel erosion and optimize pollutant removal
|
| Infiltration trench or basin |
- Not typically recommended in active karst areas due to sinkhole formation and inadequate treatment by a scarcity of underlying soils
- If used, should have supporting geotechnical investigations and calculations
- Pre-treatment should be extensive to limit risk of groundwater contamination
- Local review authority should be consulted for approval
|
| Stormwater ponds |
- Should be constructed with a synthetic or clay liner in active karst areas
- Should have supporting geotechnical investigations and calculations
- Should be limited to a maximum ponding depth (e.g. < 10 feet)
|
| Constructed wetlands |
- Should be constructed with a synthetic or clay liner in active karst areas
- Should have supporting geotechnical investigations and calculations
- Should be limited to a maximum ponding depth (e.g. < 10 feet)
|
