The River

By: Fraser Riverkeeper  09-12-2011
Keywords: Fish, Salmon, water quality

Aquaculture, or commercial/non-commercial salmon farming, has had a great impact on Fraser River. Several organizations and biologists claim that salmon farming located along west Coast of BC are responsible for the dramatic decrease of wild sockeye salmon in the Fraser River in 2009.  Salmon farming not only poses an impact on wild salmon themselves but also on water quality and human health.

Impact of aquaculture on wild fish habitat

Sea lice

The high concentration of farmed salmon promotes the development and frequent occurrence of sea lice. Sea lice are parasites that occur naturally in low numbers in the water habitat.  In the natural marine and freshwater environment, sea lice attach onto the adult salmon and feed on mucous and skin. They do not damage or physically harm the adult fish; however, with the establishment of commercial salmon farming, sea lice parasites on juvenile salmon pose a great threat or even death to the young fish.

The juvenile salmon become infested with sea lice during their passage along salmon farming areas on their journey back to the Fraser River. The sea lice infestation is therefore considered a major suspect in decline of Fraser River sockeye in 2009.

Fish escaping and cross-breeding

The farmed salmon are not native to BC; they are mostly Atlantic species.  The farmed salmon are held in open cages, or net-pens. The torn or damaged pens provide an easy escape route for the farmed salmon and their entry to the wild fish habitat. The escaped fish compete with wild salmon over food and shelters, transfer diseases and pathogens, and also interbreed with them.

Impact of aquaculture on water quality

Aquaculture has negative impact on the quality of water.  A high concentration of fish in the net-pen results in the occurrence of pathogens and diseases. To prevent this, farmed fish are fed with antibiotics and pesticides to prevent the spread of these diseases and pathogens.  Chemical residues from uneaten food and fish faeces contaminate the ocean floor and the water in the direct vicinity of the farms.   The waste can be carried away by the ocean current and cause pollution in other marine and fresh water ecosystems.

Impact of aquaculture on human health

From the human perspective, the salmon farm poses a direct threat to human by ingestion. The threat to human health rests in the high amount of pesticides, antibiotics residue, and food additives (to color grey fish meat to pink). Frequent ingestion of farmed fish can pose health risks, including cancer and resistance to antibiotics.

Salmon farm map and locations

The following links provide information on current salmon farms and locations:

Keywords: Fish, Salmon, water quality

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Geography and Geology

The Fraser Basin system comprises the main Fraser River and a huge network of tributaries that drains more than a quarter of British Columbia before the river’s egress into the Pacific Ocean through Vancouver. Its headquarters are in the Mount Robson Provisional Park in the Rocky Mountains, and it passes across the dry Fraser Plateau and through the coastal mountain ranges to the Pacific Ocean.


Watershed Facts

Discharge rate at the River mouth: The Fraser River flows at an average rate of around 3550 m3/second and dumps up to 20 million tonnes of sediment at its mouth in the Fraser Basin Delta. In addition to the industrial stresses exerted on the region, new development pressures metastasize as the vibrant Vancouver region draws more residents and more economic activity.



At the delta mouth of the river in the Lower Fraser valley, there are a number of recreational opportunities including walking, bird watching, picnicking, fishing and boating. The riverhead is in the Rocky Mountains, and there it provides a haven for canoeing, kayaking, and whitewater rafting enthusiasts. There are viewpoints, parks, trails, and an aerial tram that can take sightseers across the Fraser River.



Further exploration continued as George Simpson came to the river in 1828 to decide whether Fort Langley would be adequate as the Hudson Bay Company’s main Pacific depot. Most of British Columbia’s history is linked to the Fraser River because it was an important and essential route between the Interior and the Coast.


Water Quality

After accessing all of the site-specific conditions and how well-protected the aquatic life is, the Index ranks waterbodies in the categories of Excellent, Good, Fair, Marginal, or Poor. It drains about one-quarter of the province’s water and ranges from central British Columbia, to Southwest British Columbia and east to the Rocky Mountains near Jasper.