Pollution Concerns

Effluent from salmon farms is not captured. Instead it flows directly, untreated, into the marine environment and into contact with wild species.

Waste from fish farms is a mixture of fish feces, uneaten food pellets, drugs and drug residue, streaming continuously into the waters off of B.C.’s coast. There are presently more than 120 open net-cage fish farms currently operating in the coastal waters of B.C. producing waste that has been estimated to be roughly equivalent to the raw sewage from a city of 500,000 inhabitants. Each new open net-cage farm added in B.C. increases the volume of untreated, chemical-laden effluent entering the marine environment.

In the open net-cage systems now used, the waste simply spills through the cages, into the surrounding water and onto the ocean floor below the cages. Some of the waste on the bottom is eaten by crabs and other shellfish, but the bulk is left on the ground under the farm. There it decomposes, using up the oxygen in the surrounding water, in some cases suffocating the salmon in the farm above. Even if the farm is moved, the waste left behind renders the seabed uninhabitable for other marine life for up to five years after the farm has relocated.

The contaminants from salmon farm operations have also been linked to elevated levels of mercury in rockfish, affecting a traditional food source still used by coastal communities.