Monitoring Porous Asphalt Stormwater Infiltration and Outflow

Performance of porous asphalt (PA) was evaluated on a parking lot of the Washington State University Puyallup campus that included three pavement treatments in triplicate: maintained impervious asphalt (MIA), maintained porous asphalt (MPA), and unmaintained porous asphalt (UPA). Maintained treatments were annually swept with a regenerative air street sweeper. Infiltration rates measured annually using an infiltration ring declined over the course of the study (2011–2015) from 118 to 39  mm/min39  mm/min for the MPA, and from 134 to 54  mm/min54  mm/min for UPA, respectively. Lower infiltration rates on maintained cells relative to unmaintained cells are ascribed to the air-blast and suction cycle that characterizes the type of street sweeper used. The authors hypothesize that particulate matter was forced deeper into the porous structure of the pavement wearing course, reducing infiltration rates in the maintained cells. Annual maintenance was shown to be too infrequent and did not prevent infiltration rates from declining, with parts of the pavement cells becoming clogged. However, performance of the pavement as a whole, measured by relating total storm inflow to storm outflow, did not decline over the study period with 99.5% of storm inflow infiltrating into the porous asphalt pavement surface. Time-series analysis showed that peak flow mitigation of stormwater was considerably superior with permeable pavements in comparison with impervious pavement surfaces.

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  • English

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Filing Info

  • Accession Number: 01646622
  • Record Type: Publication
  • Files: TRIS, ASCE
  • Created Date: Aug 21 2017 4:36PM