Update to Permeable Pavement Research at the Edison Environmental Center

The EPA’s Urban Watershed Management Branch (UWMB) has been monitoring the permeable pavement demonstration site at the Edison Environmental Center, NJ, since 2010. This site has three different types of permeable pavements including interlocking concrete permeable pavers, pervious concrete, and porous asphalt. The permeable pavements are limited to parking spaces, while adjacent driving lanes are impermeable and drain to the permeable surfaces. The parking lot is instrumented for continuous monitoring with thermistors and water content reflectometers that measure moisture as infiltrate passes through the storage gallery beneath the permeable pavements into the underlying native soil. Each permeable surface of the parking lot has four lined sections that capture infiltrate in tanks for water quality analyses; these tanks are capable of holding volumes up to 4.1 m³, which represents up to 38 mm (1.5 in.) for direct rainfall on the porous pavement and runoff from adjacent driving lanes that drain into the permeable surface. Previous technical releases concerning the demonstration site focused on monitoring techniques, observed chloride and nutrient concentrations, surface hydrology, and infiltration and evaporation rates. This presentation summarizes these past findings and addresses current water quality efforts including pH, solids analysis, total organic carbon, and chemical oxygen demand. Current findings support earlier findings for pH, total organic carbon, and chemical oxygen demand where porous asphalt infiltrate values exceeded the infiltrate values of the other two permeable pavements; interestingly, porous asphalt suspended solids concentration is increasing with time.