Annacis Island Wastewater Treatment Plan (WWTP) New Outfall System
Pomerleau Bessac General Partnership (on behalf of Metro Vancouver)
Vancouver, British Columbia, Canada
March 2020 – Ongoing
The Annacis Island Wastewater Treatment Plant (WWTP) is one of our region’s largest wastewater treatment facilities. It receives and treats wastewater from 14 municipalities across the Lower Mainland so that it can be safely released back into the Fraser River.
Metro Vancouver is increasing the capacity of the current facility to meet the needs of our growing population and ensure it continues to protect the public and the environment. Planned improvements include:
- Building a new outfall pipe to carry treated wastewater from the plant to the Fraser River;
- Increasing the size of the plant and its ability to treat more wastewater;
- Repairing or replacing older parts of the existing plant;
- Strengthening the plant to reduce the impacts of an earthquake;
- Improving existing odour controls; and
- Building a more reliable back‑up power source.
Wastewater from the (WWTP) is released into the Fraser River through an outfall pipe once it has been treated. A new outfall location and diffuser system is being installed, which involves constructing a tunnel approximately one-kilometre long from the plant to the river. The new outfall location and design will ensure that treated effluent is dispersed over a broad area underwater to maximize dilution and minimize the impact on the environment.
The new pipe is expected to meet the regional growth needs for the next 100 years while ensuring greater seismic resilience and continuous, reliable and safe management of liquid waste.
Hatfield is the Qualified Environmental Professional and Environmental Manager for the Project. Hatfield prepared Environmental Protection Plans for both the landside construction and works taking place in the Fraser River, which is a highly sensitive environment. Ongoing environmental monitoring includes site inspections, the implementation of environmental plans/permits, soil and water sampling, acoustic monitoring, marine mammal monitoring, fish salvages, and addressing environmental deficiencies. Our range of specialists are also providing environmental, regulatory and technical advice, environmental orientations and training, identifying and helping to resolve environmental issues, incident reporting, and preparing frequent update reports to meet the client and regulator’s needs.