Post - Construction BMP's
The best way to mitigate stormwater impacts from new developments is to use measures, called best management practices (BMPs) or stormwater treatment practices (STPs), to store, treat, and infiltrate runoff on the development site before it can affect water bodies downstream. Innovative site designs that reduce imperviousness along with smaller-scale low impact development practices dispersed throughout a site are excellent ways to achieve the goals of reducing flows and improving water quality.
Those subject to the Virginia Stormwater Management Law and Regulations are required to address post-construction stormwater runoff from new development and redevelopments. This primarily includes developing strategies to implement a combination of structural and non-structural BMPs, and measures to ensure adequate long-term operation and maintenance of those BMPs.
The BMPs, for which design and construction standards and specifications can be found at the following links, have been approved for use in Virginia to reduce the volume of runoff and its level of pollutantion. These include non-proprietary BMPs that consist of the more traditional practices, such as ponds and infiltration devices, and others that might be classifed as low impact devlopment (LID) practices. They also include BMPs classified as proprietary or manufactured practices. The DEQ has made a conscious choice to move away from confusing labels and simply refer to all these practices as BMPs or STPs. Sizing information is included in the standards and specifications for each practice. However, additional information regarding Virginia’s uniform sizing criteria can be found in the Virginia Stormwater Management Handbook. Links to the Handbook can be found on the “References and Tools” page of this website.