Algal bloom warning for Canning River

Algal bloom warning for Canning River.
Algal bloom warning for Canning River.

RESIDENTS and visitors to the Canning region have been warned to avoid recreational activities in the Canning River at Kent Street Weir and upstream to Nicholson Bridge in the Canning River due to an algal bloom.

Environmental Health Director Jim Dodds said the blue-green bloom – species dolichospermum circinalis – was characterised by a green filamentous discolouration in the water and was capable of producing several types of toxins.

Ingesting this water could cause gastro-intestinal illness, affect nerve tissue and cause liver damage.

One of the toxins also bioaccumulates in shellfish and may cause paralytic shellfish poisoning.

Contact with the water could cause skin irritation leading to dermatitis.

Recreational activities such as swimming, canoeing, wading, fishing, crabbing, and shellfish collection in these waters should be avoided.

Pets and livestock should also be kept away from the water during the bloom.

The cities of Canning and Gosnells have erected health warning signs at the main access points leading into the river at Kent Street Weir and upstream of Nicholson Bridge to the Hester Park landing.

Anyone who comes in contact with algal-affected water should rinse it off with clean water and seek medical attention if they feel unwell.

“As a general rule people should avoid swimming in water that is discoloured or has scum on the surface, and not collect wild shellfish because their safety cannot be guaranteed,” Mr Dodds said.

Mr Dodds said commercially available shellfish from supermarkets and other commercial outlets in Western Australia were not affected by the bloom because they were managed by a strict quality-assurance program that was designed to ensure they were safe for human consumption.

Fact file:

This blue-green algae species is not uncommon to the Canning River, and the same type of bloom in the same part of the river occurred in March last year.

There is no one factor responsible for the bloom, however nutrient inflows combined with seasonal weather conditions do have a bearing.

The Department of Parks and Wildlife will continue to monitor the bloom and provide advice on algal levels to the Department of Health.

For further information please refer to the weekly Microalgae Activity Report on the Department of Parks and Wildlife website, or refer to algal bloom information found on the HealthyWA website.