The Sanitary Sewer (Wastewater) Collection System requires routine maintenance to ensure it continues to operate efficiently. This routine maintenance is completed throughout the year by flushing and inspecting the sanitary sewer mains via sanitary sewer manholes. Areas in the city that may be determined to be more susceptible to sanitary sewer problems may be flushed more often than others.
Sanitary Sewer Main Flushing
The flushing program is an integral component to the sanitary sewer collection system as it helps clean and remove residual debris and build-up from within the mains. Flusher/Vacuum combo trucks are used to flush water through the sanitary sewer main at a high velocity to remove debris and build-up from the pipe walls.
Materials and substances such as FOG (fats, oils and grease) and wipes (even those labeled as "flushable") combined with root infiltration, rocks and dirt are common causes for the build-up within a sanitary sewer main. A routine flushing program minimizes the chances of the build-up in the mains from becoming a blockage, potentially causing sewer backup or overflow which pose significant health and environmental concerns.
The goal of any sanitary sewer flushing program is to minimize service calls and sewer backup, caused by main blockages. However, the program cannot be successful without the participation of our customers. Be mindful of what you are flushing into the sanitary sewer main and only flush what the sanitary sewer is intended to collect.
Important to Note
The sewer main flushing process can cause pressure fluctuations within the sewer service laterals leading into homes or businesses and can potentially suck out the standing water in the p-traps. P-traps that have dried out can become smelly, releasing a sewer odour into your home or business. Simply fill your p-traps with hot water to eliminate the smell.
Tree Root Removal
Part of the City’s routine maintenance program is the removal of tree roots in affected areas of the sanitary sewer mains. Tree roots, if left undisturbed in the sanitary sewer mains and services, will completely block the sewer causing sewer backup. Tree roots thrive in the warm, moist sanitary sewer mains that are full of nutrients which attract the tree roots. As tree roots expand, they can cause breaks and large cracks in the sanitary sewer lines which significantly decreases the integrity of the pipe.
The most common way to clear roots from a service line is through the use of root cutters and augers. The Sewer Utility is only responsible for city owned infrastructure, providing a courtesy service where applicable. However, root removal via herbicide application is the best option within the sanitary sewer mains being that they are so much larger than a service so a cutter or auger may take too much time.
If a section of a sanitary sewer main is found to be affected by tree roots, licensed operators may administer herbicide to clear the root infiltration.
|Current Sewer Flushing Operations|
|Field Operators are currently working on Sewer Flushing in: 2019 Season Completed|
|It is anticipated that operations will next move into: TBD in 2020|
|Sewer Flushing Zone Map (PDF)|
Please Note: In addition to the routine schedule, there may be additional flushing completed in some areas of the City requiring more frequent attention. Unless the flushing activities are expected to last more than one day, that specific zone will not be noted above for these locations.