It is nearly impossible to ascribe the cause of a single event to the broader issue of climate change, the trend is clear: an increasing number of high-intensity, short-duration (HISD) events are impacting our urban areas, exacerbating the stresses on overtaxed stormwater infrastructure. The figure highlights a series of seven recent extreme rainfall events which have struck the Greater Toronto and Hamilton Area (GTHA). On August 10, 2012, a large storm tracked across Lake Ontario parallel to the Canadian shoreline. Situated only 15 km southeast of Mississauga, this event lasted 6.5 hours and had estimated sustained intensities of 150 - 200 mm/hr. While the impacts of extreme rainfall events on urban areas cannot be ignored, the increasingly prolonged, dry inter-event periods necessitate that stormwater infiltration and percolation be maximized in order sustain base flows in support of aquatic ecosystems. | It is nearly impossible to ascribe the cause of a single event to the broader issue of climate change, the trend is clear: an increasing number of high-intensity, short-duration (HISD) events are impacting our urban areas, exacerbating the stresses on overtaxed stormwater infrastructure. The figure highlights a series of seven recent extreme rainfall events which have struck the Greater Toronto and Hamilton Area (GTHA). On August 10, 2012, a large storm tracked across Lake Ontario parallel to the Canadian shoreline. Situated only 15 km southeast of Mississauga, this event lasted 6.5 hours and had estimated sustained intensities of 150 - 200 mm/hr. While the impacts of extreme rainfall events on urban areas cannot be ignored, the increasingly prolonged, dry inter-event periods necessitate that stormwater infiltration and percolation be maximized in order sustain base flows in support of aquatic ecosystems. |