The Annacis Island wastewater treatment plant treats about 175 billion litres of wastewater every year. Located in Delta at 1299 Derwent Way, the plant provides secondary treatment to wastewater for over 1 million residents in 14 municipalities. Once treated, wastewater is discharged into the Fraser River.
Metro Vancouver will be working to improve this plant to meet the needs of our growing population. These improvements will:
- increase the plant’s wastewater treatment capacity
- enhance the plant’s ability to operate in the event of a major earthquake
- allow the plant to take advantage of green energy captured on site
- allow the plant to continue to manage odour
Improvements will take place over the next several years and will include public consultation.
The wastewater treatment plant is regulated through an operating certificate issued by the BC Ministry of Environment. The treated wastewater that is discharged from the plant is required to meet standards for biochemical oxygen demand and total suspended solids, which each must not exceed 45 mg/L. On most days, the plant’s effluent contains less than 15 mg/L for biochemical oxygen demand and 15 mg/L for total suspended solids.
Recovering resources from wastewater
The plant uses anaerobic digestion to break down organic materials from wastewater to produce biosolids and methane gas. The methane from this process is then used to generate heat and electricity that is used to run the plant. The Annacis Island plant produces enough energy to meet all of its own heat requirements and about 50% of its electricity requirements. This reduces its greenhouse gas emissions by 660 tonnes every year. The plant produces about 42,500 bulk tonnes of biosolids every year.