Best Management Practices (BMPs) Siting Tool
EPA’s Best Management Practices (BMPs) Siting Tool identifies potential suitable locations/areas for implementing different types of BMPs or low impact development (LID) controls. It supports users with selecting suitable locations that meet the defined site suitability criteria, such as drainage area; slope; hydrological soil group; groundwater table depth; and road, stream, and building buffers. It is designed to be used by anyone interested in reducing runoff from a property, including site developers, landscape architects, and urban planners.
BMPs for Managing Stormwater Runoff
BMPs treat rain where it falls. They address three criteria that are critical to managing urban stormwater runoff and reducing combined sewer overflows (CSOs):
- Volume: Reduce or delay the volume of stormwater that enters the sewer system.
- Peak Discharge: Reduce the maximum flow rate into the combined system by decreasing the stormwater volume and lengthening the duration of discharge. This inherently lowers the frequency of combined sewer overflows.
- Water Quality: Improve water quality through volume reduction, filtering, and biological and chemical processes.
Because they prevent, intercept, and treat stormwater near the source, stormwater BMPs can be adapted to meet stormwater management goals.
Types of BMPs
BMPs are classified and conceptualized as scale-based and type-based. The scale-based category classifies them according to the size of the application area, such as lot-, community-, or watershed-scales. The type-base category classifies them into three types according to the geometric properties:
- Point BMPs: Practices that capture upstream drainage at a specific location and may use a combination of detention, infiltration, evaporation, settling, and transformation to manage flow and remove pollutants.
- Linear BMPs: Narrow linear shapes adjacent to stream channels that provide filtration of runoff, nutrient uptake, and ancillary benefits of stream shading, wildlife habitat, and aesthetic value.
- Area BMPs: Land-based management practices that affect impervious area, land cover, and pollutant input.
The following structural BMP options are supported.
| Point BMP | Linear BMP | Area BMP |
|---|---|---|
| Constructed Wetland | Grassed Swale | Green Roof |
| Infiltration Basin | Infiltration Trench | Porous Pavement |
| Bioretention | Vegetated Filter Strip | |
| Sand Filter (surface) | Sand Filter (non-surface) | |
| Rain Barrel | ||
| Cistern | ||
| Wet Pond | ||
| Dry Pond |
Benefits of Using BMPs
- Promotes the natural movement of water, instead of allowing it to wash into streets and down storm drains.
- Can blend in with the landscape and infrastructure.
- Can be infrastructure, such as a permeable parking lot.
- Can provide aesthetic effects.
- Can reduce the amount of pollutants entering the water collection system.
- Can improve water quality and the water treatment process at water treatment plants.