Sewage pollution from outdated onsite and municipal sewage treatment facilitates are the main contributors to municipal pollution in the Georgia Strait, Burrard Inlet, and Fraser River. In metropolitan Vancouver and the increasingly populated Fraser Valley, municipal sewage pollution contains a large number of toxic substances such as pathogens (bacteria and viruses); nutrients such as nitrogen and phosphorus are also a problem. Increased nutrients in the water can lead to excessive plant growth (such as blue-green algae).

When sewage material decays and algal material grows, they take up oxygen in the water, which is exasperated in the warmer summer months. This process reduces the amount of oxygen available to marine invertebrates and fish at high discharge rates.

Municipal sewage waste can also create potential health risks for recreational users of the waterways. Polychlorinated byphenols (PCBs) were banned from production in the 1970s but are still found in the bottom layers of sediment and can be discharged back to the air. PCBs can affect the neurological, immune, and reproductive systems of mammals and also are known to cause cancers.

The Iona wastewater treatment plant is located in the city of Richmond, just north of Vancouver International Airport. It serves a large portion of the metropolitan Vancouver population. It provides only primary sewage treatment before disposing the effluent in a deep-sea outfall in the Georgia strait. Both the Iona and the Lionsgate treatment facilities require urgent upgrades (see Ottowa Riverkeeper and Eco-Justice).

Also, approximately 150,000m3 of sewage effluent is discharged into the Fraser River Basin from sewage treatment plants located upstream from the town of Langley, close to the mouth of the river. The Hope treatment plant located upstream has only primary, not secondary, treatment of the sewage.

Resources:

Metro sewage plants failing federal test

Hidden killer: Sewage from Greater Vancouver and Greater Victoria is Georgia Straight’s number one pollution threat