Permeable Pavement
What is Permeable Pavement?
Permeable pavements are paved surfaces that infiltrate, treat, and/or store rainwater where it falls. Permeable pavements may be constructed from pervious concrete, Permeable Pavement porous asphalt, permeable interlocking pavers, and several other materials. These pavements are particularly cost effective where land values are high and where flooding or icing is a problem. Permeable pavement is designed to allow percolation or infiltration of stormwater through the surface into the soil below where the water is naturally filtered and pollutants are removed. In contrast, normal pavement is an impervious surface that sheds rainfall and associated surface pollutants forcing the water to run off paved surfaces directly into nearby storm drains and then into streams and lakes. Pervious surface coverings, if installed correctly and properly maintained, duplicate the structural and functional features of traditional pavement.
Applications
Scientific studies have linked high levels of impervious surfaces to water quality degradation. Two thirds of the impervious surfaces in developed communities are in the form of pavement related to automobile usage. Any design that uses alternatives to reduce impervious pavement is a positive step towards improving the quality of a community’s water resource.
Permeable pavements are a recognized runoff reducing substitute for normal pavements in development or redevelopment of:
- Driveways, including residential driveways, low-traffic roads, fire lanes and emergency access roads;
- Parking areas; especially over-flow parking and those associated with office buildings, shopping centers and recreational facilities ;
- Sidewalks;
- Road shoulders and vehicle cross-overs on divided highways;
- Boat launching ramps;
- Others, including pool decks and patios.
The use of permeable pavement has been found to:
- Reduce storm water runoff. (Even when permeable pavement structure is saturated, its rough surface texture continues to slow surface flow of stormwater);
- Replenish groundwater;
- Reduce flooding which may over-load combined sewer sewage treatment plants;
- Require less land set aside and cost for development of retention basins;
- Reduce pollutants in run-off;
- Reduce irrigation of area plantings based on the seepage of rain into the sub soil surfaces
- Reduce thermal pollution;
- Lessen evaporative emissions from parked cars;
- Reduce glare and automobile hydroplaning (skidding) accidents;
- Reduce pavement ice buildup.
