BMPs - Structural
Quantity Control Devices: These include detention/retention ponds, constructed wetlands, dams and check dams and rain barrels. Ponds and wetlands also provide some biological treatment of polluted water, as well as habitat for fish and wildlife.
Filtration Devices: These include bio-filters, grassy swales, sand filters, catch basin inserts, manufactured bags and booms or skimmers. They remove particulates and associated pollutants such as heavy metals and phosphorous.
Infiltration Devices: These include underground stormwater storage vaults, bio-retention areas, porous pavement, dry wells, dry swales, infiltration basins and infiltration trenches. They allow stormwater to return to the ground, rather than simply run off impervious surfaces.
Hydrodynamic Devices: These are special structures that concentrate and remove sediment, litter and other floatable solids, and oil. They include proprietary devices such as BaySaver®, Stormceptor®, and Aquaswirl®.
Erosion Control Devices: These include silt fences, erosion blankets, vegetative covers, riprap (stone) coverings or barriers, mulches, and sandbag dikes. Detention practices that slow the peak flow of stormwater also serve to decrease erosion in stream channels.