Stay connected with LSRCA

RSS FeedSubscribe to our YouTube ChannelLike us on FacebookFollow us on Twitter


Phoslock - How it Works

Phoslock is made by combining bentonite, a naturally occurring clay, with lanthanum, a malleable and ductile metallic element notably given as medical treatment to kidney disease patients to reduce phosphates in their blood. Neither bentonite nor lanthanum are harmful in the concentrations to be applied in this project.

Phoslock is mixed with water, taken from the water body itself, to form a slurry, which is then spread on the surface of the water. As the Phoslock particles sink, dissolved phosphorus binds with the lanthanum to become an insoluble compound. The bond between lanthanum and phosphorus is virtually unbreakable, making the phosphorus no longer available to plants and algae.

On the bottom of the water, Phoslock forms a fine layer of sediment that effectively traps other phosphorus, preventing future releases of the nutrient from being available to plants in the soil bed under the water.

Extensive testing of Phoslock has shown it removes up to 95 per cent of the phosphorus in the water. Tests indicate that it is not harmful to the water nor to aquatic organisms when properly applied. The product has been widely used throughout Australia, the USA, New Zealand, China, Holland, and Germany to treat, lakes, rivers, stormwater ponds, and drinking water reservoirs.

Find out more:

Testing Phoslock in the Lake Simcoe Watershed