Separating sewage from rainwater
Vancouver is working toward the Province of BC's environmental goal to eliminate sewage overflows by 2050. As the City replaces combined sewer systems with separated sewer systems, properties will also need to have separated sewer systems.
In a combined sewer system, stormwater runoff is combined in a single pipe with wastewater from homes, businesses, and industry.
During drier weather, the stormwater and wastewater are carried to the sewage treatment plant together. But in heavy rains, high volumes of stormwater can exceed the capacity of a combined sewer system. The excess, untreated amounts overflow and empty directly into our waterways.
Benefits of a separated sewer system
In a two-pipe separated sewer system, stormwater is collected through storm drains. It travels through different pipes than household sewage and other wastewater.
Separating stormwater from wastewater is better because it:
- Eliminates combined sewer overflow
- Prevents flooding by increasing capacity
- Allows stormwater to be used as a resource
How the City prioritizes sewer replacement
There are two sewer separation programs running concurrently in the City. The overall sewer mains are being separated so that storm drains carry stormwater runoff separately from other wastewater.
Similar work is being done to separate the sewer mains that serve private properties. This project focuses on smaller areas based on the following conditions:
- There is a documented history of sewer line blockages for which the City was fully or partially responsible
- An indication that a City managed sewer line maintenance program is no longer effective or has become exhaustive
- The property owner has fully replaced the private property portion of the sewer line and reports that the City portion is in poor condition
The City has a separated sewer system in the following areas:
- West End
- Mt. Pleasant
- Burrard Inlet and Fraser River shorelines
By 2020, the City plans to install separated sewers in these areas:
- Point Grey
If you are a property owner in these areas, you will be notified when the City begins to replace the sewer system in your area. You should plan to upgrade the sewer connection on your property at that time, at your own expense.