You are here:
Research Update from EPA Permeable Parking Lot in Edison, NJ
Citation:
Brown, R. AND Mike Borst. Research Update from EPA Permeable Parking Lot in Edison, NJ. Presented at 9th New Jersey Water Monitoring Summit, Bordentown, NJ, November 28 - 29, 2012.
Impact/Purpose:
This presentation will highlight several general results collected from the EPA permeable parking lot in Edison, NJ, after three years of monitoring.
Description:
Communities are increasingly installing green infrastructure stormwater control measures (SCMs) to reduce pollutant loads associated with stormwater runoff. Permeable pavement is a SCM that has limited research on working-scale, side-by-side performance of different pavement surface types. In 2009, the U.S. EPA constructed a 0.4-ha (1-ac) parking lot in Edison, NJ, that was surfaced with three different permeable pavement types [interlocking concrete pavers (ICP), porous concrete (PC), and porous asphalt (PA)]. Each permeable surface has four equally-sized, lined sections that drain to collection tanks that enable composite sampling for water quality analysis. Each lined section is 55 m2 (590 ft2) and has an impervious hot mix asphalt contributing drainage area of about 36 m2 (390 ft2). Samples analyzed in this presentation were collected at roughly monthly intervals for more than two years. Samples were also collected and analyzed from rainwater, rooftop runoff, and asphalt runoff to provide comparisons to the infiltrate. Some of the stressors measured include: nutrients, chloride, heavy metals, suspended solids, and pH. For some stressors, the exfiltrate concentration varied by surface material. Surface infiltration rate was measured by following a modified version of ASTM C1701. Six randomly selected locations were tested on each surface monthly from December 2009 to May 2010, September 2010 to May 2012, and August 2012. Infiltration rates were significantly different across each surface. Overall, there has been little change in infiltration rate with time for any surface, so maintenance has not been performed to date. A reason for the longevity has been attributed to the clogging dynamics. Runoff transports solids to the upgradient edge of the permeable pavement surface, and the solids concentrate and collect at this location as the runoff infiltrates through the surface. As clogging progressed from the upgradient edge, the method of selecting a random location across the entire area typically resulted in not measuring a meaningful change in infiltration rate.
