**** HRM Media Release
Risk advisory for Shubie Canal pond has been lifted
The Halifax Regional Municipality is advising residents that the blue-green algae risk advisory previously in effect for the Shubie Canal pond near Fairbanks Centre in Dartmouth has been lifted.
Blue-green algae (cyanobacteria) is naturally occurring in freshwater environments and may become visible when weather conditions are calm. These organisms can multiply rapidly during the summer, leading to extensive growth called a bloom. Some types of blue-green algae produce toxins during blooms and when these blooms decay, the toxins may be released into the water, posing a risk to people and pets.
Tests have confirmed that the bloom in the pond consists of green algae, not blue-green algae, so there is no risk of toxin exposure.
Risk advisories are issued based on a number of factors, including the visual observation of algae blooms, test results and information regarding the current life cycle phase of algae blooms. As algae blooms die and decay, toxins are released. Unsafe toxin levels can remain in the water even after the bloom is gone.
When an algae bloom is observed, a risk advisory is issued and initial testing is done to determine whether the algae bloom is toxin producing. If the algae bloom is not toxin producing, the risk advisory will be lifted and no further testing is required.
If the algae bloom is toxin producing, the risk advisory will remain in effect until blooms have disappeared and post-bloom test results indicate water is within safe limits.
To learn more about algae blooms, visit http://www.halifax.ca/about-halifax/energy-environment/harmful-algae-bloom