Changes

Flooding is a major environmental and economic challenge, particularly in urban areas where impervious surfaces prevent natural infiltration. Flooding can result in traffic interruption, economic loss, infrastructure damage, basement flooding and other undesirable consequences. [[Climate change]] is increasing the frequency and intensity of extreme rainfall events, exacerbating flood risks. This will be particularly severe in older areas where the minor system was not designed to today’s standards and/or major drainage system pathways have been altered or do not exist. Catastrophic losses from flooding have been steadily rising in Canada over the last two decades.

Flooding is a major environmental and economic challenge, particularly in urban areas where impervious surfaces prevent natural infiltration. Flooding can result in traffic interruption, economic loss, infrastructure damage, basement flooding and other undesirable consequences. [[Climate change]] is increasing the frequency and intensity of extreme rainfall events, exacerbating flood risks. This will be particularly severe in older areas where the minor system was not designed to today’s standards and/or major drainage system pathways have been altered or do not exist. Catastrophic losses from flooding have been steadily rising in Canada over the last two decades.

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Hydrological changes associated with urbanisation are increased storm runoff volumes and peak flows (Qp), faster flow velocities and shorter time of concentrations. A reduction in infiltration generally leads to less groundwater recharge and baseflow.The flashy response results in tremendous stresses for the urban stream and downstream receiving areas (Walsh et al., 2005)."''

"Hydrological changes associated with urbanization are increased storm runoff volumes and peak flows, faster flow velocities and shorter time of concentrations. A reduction in infiltration generally leads to less groundwater recharge and baseflow. The flashy response results in tremendous stresses for the urban stream and downstream receiving areas" (Walsh et al., 2005).}}

In order to protect downstream properties from flooding due to upstream development, Conservation Authorities establish flood control for future SWM planning through regularly updated of Hydrologic Studies and Subwatershed-level Stormwater Management Studies that characterize flood flow rates, define the location and extent of Flood Damage Centers and assess the potential impact of further urbanization. Flood mitigation strategies that incorporate Low Impact Development (LID), traditional stormwater management, and hybrid infrastructure can manage stormwater effectively and reduce flood impacts.

In order to protect downstream properties from flooding due to upstream development, Conservation Authorities establish flood control for future SWM planning through regularly updated of Hydrologic Studies and Subwatershed-level Stormwater Management Studies that characterize flood flow rates, define the location and extent of Flood Damage Centers and assess the potential impact of further urbanization. Flood mitigation strategies that incorporate Low Impact Development (LID), traditional stormwater management, and hybrid infrastructure can manage stormwater effectively and reduce flood impacts.