Sewer inspection, rehabilitation and maintenance
District Operations is responsible for the inspection, cleaning, and maintenance of over 9,000 kilometres of sewers (storm, sanitary and combined) in order to ensure uninterrupted service. The section also makes sure that the city’s major watercourses (streams and rivers) are free of blockages and obstructions.
Inspection
Sewers are inspected to determine the need for structural repairs and/or maintenance. Inspection and assessment is carried out by means of:
- visual observation
- closed circuit TV camera
- dye tracing
- flow monitoring
Maintenance
Maintenance is performed on both main sewers and lateral connections to remove the following materials:
- calcite buildup
- tree roots which penetrate the sewer
- grease accumulation
- sediment buildup (in catchbasins, sewers and laterals)
The removal of the above materials is performed by a number of maintenance processes, but typically achieved by flushing the material using a high pressure jet of water, and collecting and disposing of the deposited materials.
Repairs, rehabilitation
When the need for repairs or rehabilitation is found, one or more of the following is carried out:
- cracks and joints are sealed
- pipe sections are replaced or lined
- manhole and catchbasin structures are replaced or repaired
District Operations also responds and assists with a number of environmental issues including spill response and mitigation.