Stormwater Management
Stormwater is rain and melted snow that does not soak into the ground and becomes surface runoff. The water flows into storm sewers and nearby streams and rivers.
Stormwater management manages the water that comes from impervious surfaces. Rural areas, such as farmland, pastures and woodlands, are usually pervious. These areas absorb the rainfall and generate a small volume of runoff. Urban areas contain a higher percentage of impervious surfaces. Large amounts of water runoff can overwhelm natural channels and streams, causing erosion, localized flooding, and property damage.
Purpose
The purpose of stormwater management is to maintain natural water sources. It is important to protect them from the effects of urban development. A stormwater management control strategy reduces the chance of flooding, stream erosion and water pollution in urban areas.
Management
Oshawa manages stormwater in three ways:
| Control option | Examples |
|---|---|
|
Source |
Rain barrels, downspouts and cisterns, rain gardens etc. |
|
Conveyance |
Conveying stormwater via storm drains/sewers, swales, channels etc. |
|
End-of-pipe |
Control the effects of urbanization for flood and erosion control and water quality improvement and include stormwater management ponds, wetlands, infiltration basins etc. End-of-pipe facilities temporarily store stormwater runoff and release it at a controlled rate. Although the volume of runoff does not decrease, it reduces the risk of flooding as all the stormwater runoff does not arrive at the stream at the same time. |