Algae blooms throughout BC Interior

Concerns about water safety for human and animal consumption for drinking and for recreation.

Observation: A number of freshwater bodies, of varying sizes, have seen significant algae blooms this year. Access to these water bodies for drinking water and recreation has been restricted as some species of cyanobacteria produce microcystin toxins that are hazardous to humans and animals. Further, access to the bodies of water by animals has also been restricted due to the potential for these toxins to impact livestock and pets.

There is no visual way to identify whether there are toxins present, or whether the species of algae are capable of producing microcystins. As such, health authority staff must rely on field testing, which provides presence/absence for the toxin in a very small sample size, or laboratory sampling, which takes up to two weeks, during which access must be restricted.

In one recent algae bloom noted in Douglas Lake, a number of dead fish were found near the shoreline. Dissolved oxygen available for the fish was depleted from the water as a result of the algae bloom. The attached image shows the same stretch of shoreline on Douglas Lake during the largest part of the bloom, and after algae levels had receded. -Casey Neathway, Interior Regional Manager, First Nations Health Authority (FNHA).

LEO BC Network Coordinator comments: Unusual blooms of Cyanobacteria---blue-green algae---in lakes occurs with increases in the input of nutrients, such a phosphorous, from agriculture, laundry detergents, wastewater, landscaping, changes in forestry practices and watershed function, disturbances on watersheds such as fires, and changes in wildlife populations. Patterns of observed algae blooms can help determine their drivers. - Tom Okey, Ocean Integrity Research and the University of Victoria School of Environmental Studies.

Resources:

Blue-green Algae (Cyanobacteria) Blooms, HealthLink BC

Blue-Green Algal Blooms in Lakes, Ministry of Environment

Blue-green Algae (Cyanobacteria), Okanogan Basin Water Board