How the System Works

Every day, Metro Vancouver residents, businesses and industries produce about 1 billion litres of wastewater. This wastewater is collected through a region-wide network of sewers, which carry it to wastewater treatment plants.

What’s in wastewater?

Water becomes wastewater once it has been “used” in some way. About 80% of wastewater comes from our homes, when we use toilets, sinks, showers, washing machines and do anything else that sends water into a drain or pipe. Wastewater can also include stormwater from rain and other water that is not absorbed into the ground.



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How the collection system works

Once it leaves a building, wastewater flows into municipal sewer pipes and then into larger, regional trunk sewers. Pumping stations keep wastewater moving through the system until it reaches one of the region’s five wastewater treatment plants.

A different collection system also captures stormwater from rainfall and other sources. Stormwater goes into a separate system of stormwater sewers—usually municipal—which discharge directly into the nearest body of water. In older parts of the region, some stormwater goes into combined sewers, which carry both stormwater and sewage. The collection system also takes in stormwater in drainage areas around rivers and streams.

Metro Vancouver’s role

The majority of wastewater collection is done by municipalities, which account for over 8,500 km of the region’s sewer pipes. Metro Vancouver is responsible for about 530 km of trunk sewers (larger pipes that connect to municipal sewers) and 33 sewage pumping stations. Its major responsibility is operating the region’s five wastewater treatment plants. Metro Vancouver also works with municipalities to manage stormwater and drainage issues.

Maintenance and upgrades

Metro Vancouver maintains and upgrades the wastewater collection system on an ongoing basis (see current sewer construction projects). Regularly scheduled maintenance includes:

  • using remote video cameras to locate faulty trunk sewers and to monitor pipe and wastewater flows within the system
  • performing preventative sewer cleaning and maintenance, based on information provided by monitoring systems; and
  • repairing or replacing trunk sewers and other structures in the regional wastewater collection system

Metro Vancouver also works with municipalities to set priorities for inspecting, upgrading and repairing municipal sewer systems.

Problems in the pipes

Some of the things that we put down our sinks and toilets cause serious problems for the region’s sewers. Grease, disposable wipes and other items can clog sewers and damage pumping equipment, causing sewage to overflow into the environment. Find out what residents and businesses can do to help keep the region’s wastewater system running well.