Is the groundwater table at risk of pollution from the infiltrating stormwater?
Pollution is possible if an infiltration BMP is not placed in the proper area. Siting of this BMPs is critical to their success. These systems should not be used in areas where high-levels of contaminants are present. The Villanova Pervious Concrete / Porous Asphalt Comparison Site is a good example of a clean site; the major source of pollution is from the automobiles that park in the parking lot. Stormwater is naturally cleaned as it moves through the soil stratum, so small amounts of metals and nutrients can be cleaned out and retained in the soil just as if they were infiltrated through pervious grass or wooded areas. Parking lots, driveways, and walkways are ideal locations for these infiltration systems.
