Learn what the City is doing to ensure the sanitary sewer system functions properly.

City of Surrey has one of the largest sanitary sewer systems in the province. It is made up of more than 1,500 km of sanitary sewer pipes that carry wastewater from one point to another by gravity, and service connections that connect homes and businesses to the sanitary sewer system.

Within the system there are 21,000 manholes and 80,000 inspection chambers that allow the City to access and maintain the sanitary sewer system. There are also 40 pump stations that pump wastewater from a lower elevation to a higher elevation, where wastewater cannot be carried to a sanitary sewer by gravity.

The system also features forcemains and siphons that carry wastewater under pressure from one point to another, as well as odour control facilities that address issues at specific locations.


We regularly inspect the sanitary sewer system and fix issues to make sure that the system:

  • Has no blockages and is working properly
  • Is not broken or collapsed at any location(s)
  • Is reducing the risk of rainwater and groundwater entering the sanitary sewer system.

The City inspects and maintains the entire sanitary sewer system except for the service connection between your home or business and your property line, which is your responsibility to maintain.


Our inspection and maintenance work includes:

Video inspections

A camera takes a video as it travels through a sanitary sewer. City staff review the video and identify issues in the sewer, such as cracks, leaks, blockages, dips, roots, fats, oils and grease deposits, or breaks in the pipe. New sanitary sewers are also video inspected to confirm that they have been built properly.

Smoke testing

A non-toxic vapour (that looks like smoke) is added to the sanitary sewer. If the smoke comes out of a roof downspout or cleanout on a house or building, then there is a possible cross connection (meaning rainwater or groundwater can enter the sanitary sewer system). Cross connections are a violation of the City’s Sanitary Sewer Bylaw No. 16611 and should be fixed by the property owner immediately. Smoke testing can also identify broken or missing lids or caps on inspection chambers and manholes.

Dye testing

A coloured, non-toxic liquid is added to a roof downspout or building foundation cleanout. If the dye appears in the sanitary sewer, then there is a cross connection. Similarly, if dye is added to a drain in a house or building and the dye appears in the storm sewer, this is also a cross connection. Cross connections must be fixed by the property owner immediately per the City’s Sanitary Sewer Bylaw No. 16611.

Pressure testing

A small section of the sanitary sewer is isolated using “bladders” and air is added to the isolated section to pressurize the pipe. A gauge then reads the air pressure in the isolated section over time. A drop in air pressure indicates that there is a leak or crack in the pipe. A gel-like substance (called grout) may be added to seal off the leak or crack in the pipe.


Water is injected into a sanitary sewer to move debris that is stuck. The debris is removed by a vacuum truck at a downstream manhole.

Fat, oil and grease removal

A circular rotating saw is sent through the sanitary sewer to cut and remove hardened deposits that have attached to the pipe.

Root cutting

A circular rotating saw is sent through the sanitary sewer to cut tree and vegetation roots that have entered the sanitary sewer through cracks or joints in the pipe. Sometimes cutting the roots actually makes the root system grow faster (pruning effect), so property owners are warned not to plant trees, shrubs or other large plants over sanitary sewer pipes. See what a sanitary sewer full of roots looks like.

Responding to Sanitary Sewer Issues

Emergency issues are repaired as soon as possible. Any remaining issues are added to the City’s upcoming projects list.

See how to report a problem with your sanitary sewer.

Low Pressure Sewer Systems

Low Pressure Sewer (LPS) systems are built in areas that cannot be serviced by the City’s gravity sanitary sewer system and when the area is too small to build a community pump station at a reasonable cost.

Learn more about LPS systems.

Future Sanitary Sewer Projects

The City's annual capital construction program and 10-year servicing plan identifies sanitary sewer system upgrades needed to service the community over the next 10 years. All sanitary sewer system components are designed in accordance with the City's design criteria.

Find out more about current and past tenders, as well as requests for proposals, quotations and information for the sanitary sewer program.