Engineered for installation in growing medium on green roof systems, a 6" diam. stainless steel mesh covered receptacle collects drainage at ground level atop a sturdy 3" diam. perforated bronze standpipe. The standpipe channels drainage to a 12" diameter corrosion resistant, Duco coated cast iron drain installed in roof decking while extracting excess moisture from the surrounding growing medium ensuring optimal growing conditions for rooftop plantings.