Thomas Jefferson University Lubert Plaza Methods

Abstract

Environmental Increased pervious area by 570% over former sitePervious and impervious surfaces before and after construction of the park were compared. The previous 1.8 acre site contained 93% impervious surfaces and the Lubert Plaza design reduced the impervious surfaces to 60% of the total site area. The area of the new building plus hardscaping was subtracted from the total site area to determine the total area of pervious surface. The pervious surface included planting beds, tree wells, and turf areas. . Compared with the total site area (adjusted to remove public right of way), the new design has approximately 40% pervious cover compared with the previous site's 7% pervious cover.  Captures and reuses up to 17,700 gallons of air conditioning condensate for irrigationAn underground cistern, located at the southeast corner of the site, provides approximately 17,700 gallons or 2365 cubic feet of storage. Pipes carrying stormwater and air conditioner condensate leading from the roof of the adjacent building are connected to the cistern. The volume was computed based upon data provided in the contract documents related to the cistern's dimensions and storage capacity. The cistern is comprised of plastic Atlantis Matrix Rain Tank modules with the perimeter wrapped in a non-woven geotextile and then a geomembrane. A weir assembly directs stormwater overflow to the City's combined sewer system. Irrigation demands beyond the amount provided by the cistern are supplied by Philadelphia's potable water system.