Plants and soils are under valued players in managing stormwater and green infrastructure performance.
A case study of Shoemaker Green designed by Andropogon Associates on the campus of the University of Pennsylvania, “Wet Lab” authored by Emily McCoy in the November/December 2014 issue of gb&d (Green Building and Design) said one of the most important findings from early results from a five-year site performance monitoring plan by the Earth and Environmental Science Department was just how “undervalued” plant material and soils are in managing stormwater. In the year May/2013 to June/2014 no stormwater left the site even with supersized 3”+ rain events. “Transpiration measurements of the vegetation show that native floodplain species and umcompacted turf are veritable workhorses, transpiring anywhere from three to ten gallons of water per day during the growing season.” Function during winter events was not as good, causing designers to readdress increased system capacity for winter months. (2014) gb&d.