A stormwater oil and grit separator is an underground device that captures oil and sediment from storm events, runoff and snowmelt. Capturing these contaminants prevents them from entering Nose Creek, and eventually the Bow River.
Oil and grit separators are located at:
Oil and other contaminants collect on parking lots, driveways and roads. They are carried to an oil and grit separator by rain and snow melt. A stormwater oil and grit separator's design allows the device to separate oil and sediments into different containment areas until they can be cleaned out. The oily substances rise to the top of the containment area, and sediment settles at the bottom of the unit, allowing clean water to flow directly into the City’s storm drainage system.
Stormwater oil and grit separators collect a particular volume of sediment and oil before a clean-out is required. Therefore, cleaning frequency depends on the unit's size and site conditions, such as the size of the drainage area and the type of activities undertaken on the site.
Under the Drainage Bylaw No. B-03/2014 (pdf) the City requires that the Interceptor, device or practice is in good working condition at all times and is serviced often enough so it does not become overloaded.
Inspections may be performed by the device’s manufacturer, or a designate. On a private site it is the owner’s responsibility to retain a contractor to clean and dispose of the contents of their oil and grit separator.
Cleaning and/or maintenance requirements are to be based on inspection results.
The City requests that stormwater oil and grit separator maintenance records are submitted to water.services@airdrie.ca annually.