Long-term effects of three types of permeable pavements on nutrient infiltrate concentrations.

There is limited information about long-term effects of permeable pavement parking lots on concentrations of nutrients in infiltrates. A 0.40-ha parking lot that contained three types of permeable pavement including permeable interlocking concrete pavement (PICP), porous asphalt (PA) and pervious concrete (PC) was constructed in 2010 at a U.S. EPA facility in Edison, New Jersey. This study was conducted from October 2010 to August 2017. Water quality samples were collected from the rainfall, parking lot runoff, and infiltrate from these three pavement types. Samples were analyzed for parameters including NH3-N, NO2-N, NO3-N, TN, PO4-PO4, TOC, ORP and pH. Statistical methods were used to study infiltrate concentration changes with time. Results showed, for all analytes, there were no differences between permeable interlocking concrete pavement and pervious concrete median concentrations. Data showed distribution of species changed and supported nitrification processes. The trend varied with source. Nitrogen species showed slowly increasing trends in rainwater, PC and PICP infiltrate concentrations while phosphate concentration showed a slightly increasing trend in rainwater and porous asphalt infiltrate. It is recommended that communities select PC and PICP when nitrogen species are the pollutants of concern and PA is more suitable for orthophosphate removal.