A right-of-way LID for stormwater management

Recent rainfall research in Ontario has pointed out the trend of increasing rainfall events in winter and spring seasons.  In order to provide stormwater management, low impact development practices should be designed accordingly.  A right-of-way LID, termed Etobicoke Exfiltration System (EES), was designed and constructed in early 1990 in Toronto and was found to provide significant stormwater control in urbanized area.  The design manual has recently been prepared for Ontario Ministry of the Environment and Climatic Change Road.  This presentation will outline the planning, design, and construction procedure.  An EES is designed to manage stormwater over four seasons by retrofitting roads with two 200 mm (8 inches) perforated pipes with end capped below a storm sewer system.  The design concept is to direct road runoff up to 13 mm of rainfall to these two perforated pipes with end capped and fill the void space of the sewer trench for exfiltration to the surround soil at all times (i.e. including snowmelt and winter rainfall). Two and a half kilometer of this exfiltration system was constructed in the City of Toronto and found (by monitoring) to be able to control rainfall up to 24 mm without overflowing to the storm sewer above.