Design Considerations Common To All Permeable Pavements

Impervious cover in watersheds without controls result in increased stormwater runoff and decreased groundwater recharge in response to rainfall events. This increased runoff can be the cause of negative impacts to municipal drainage systems, natural resource areas, and private properties. Impacts from impervious cover runoff can include increased stormwater flow volumes and velocities that can cause flooding and/or erosion; the transport of stormwater-related pollutants/debris from impervious surfaces to resource areas and drainage system components; the reduction of rainwater recharge to support groundwater systems and stream baseflow; and overall physical and chemical changes to the natural hydrologic system in a watershed. A key goal for improving and/or protecting the nation's water resources is the reduction of impervious cover in watersheds. For more than 25 years in the United States, there has been a continual increase in the development and implementation of stormwater management regulations with new requirements and design guidelines. These efforts are focused on preventing negative impacts as described above. Permeable pavement is a stormwater management practice that can reduce impervious surfaces in watersheds and related impacts.