Long-Term Characteristics of Infiltration Best Management Practices

Infiltration Best Management Practices (BMPs) are becoming a widely used tool in an effort to better manage storm water runoff. Many new storm water regulations require the implementation of storm water BMPs to reduce the volume of storm water runoff. The most widely implemented volume reduction BMPs are engineered infiltration practices. Even with such widespread use questions remain about how infiltration BMPs will function over the course of a year and more importantly; their lifetime. The focus of this research is on the actual infiltration process central to the operation of such BMPs. In total approximately ten years of hydrologic monitoring data were collected at three infiltration BMPs located on the campus of Villanova University in Southeastern Pennsylvania. The BMPs include a Pervious Concrete Infiltration Basin, a BioInfiltration Traffic Island, and an Infiltration Trench. Analysis of the monitoring data has provided valuable insight into the characteristics of long-term concentrated infiltration of storm water runoff. An attempt has been made to normalize their performance and provide information that could be relevant to any infiltration BMP. The BMPs all show significant seasonal variation and only one demonstrates a systematic decrease in performance.