A detention basin or retarding basin is an excavated area installed on, or adjacent to, tributaries of rivers, streams, lakes or bays to protect against flooding and, in some cases, downstream erosion by storing water for a limited period of time. These basins are also called "dry ponds", "holding ponds" or "dry detention basins" if no permanent pool of water exists.
Grass swales are shallow, sloped, densely vegetated triangular channels designed to treat stormwater runoff. Similarly, grass buffers are vegetated areas surrounding wet basins and wetlands. As water flows over these swales and buffers, vegetation slows the water and allows for sedimentation and filtering of pollutants through the subsoil.
Proprietary BMPs A proprietary BMP is a pre-fabricated stormwater treatment structure utilizing settling, filtration, absorptive/adsorptive materials, vortex separation, vegetative components, and/or other appropriate technology to remove pollutants from storm runoff.
Rain gardens, also known as porous landscape detention, are engineered landscaped depressions that provide bioretention of pollutants in stormwater runoff. Bioretention removes pollutants through multiple processes including sedimentation, filtering, adsorption, evapotranspiration, and biological uptake.
Stormwater Planters Stormwater planters are structural containers with open bottoms that allow stormwater runoff to filter through the reservoir and infiltrate slowly into the ground below. Stormwater planter boxes can either be infiltration planters (designed to infiltrate through native soils) or flow-through planters (designed with an impervious liner and overflow pipe).