GREAT LAKES BASIN
Not only is this globally significant ecosystem at the heart of Canada’s economy, it is teeming with life. Within its diverse ecosystem we find turtles, moose, wolves, bald eagles, waterfowl and more than 200 species at risk.
A watershed under threat
WWF’s Watershed Reports found that is faces very high threats from pollution, habitat fragmentation, overuse of water and invasive species, jeopardizing the health of wildlife – and people too. But perhaps even more alarming is the fact that we don’t collect enough data to know just how much damage all this stress is causing.
Where the water flows, the salt goes
In southern Ontario, rapidly increasing levels of chloride (Clˉ), caused by the excessive use of road salt in the winter, is having a devastating impact on the freshwater ecosystems of the Great Lakes.
In the winter we use too much salt, often 30 times more than what is needed for safe roads and walkways. The salt spread on our pavement doesn’t disappear with the snow and ice, and instead it seeps into soil or flows from roads and parking lots into sewers and then into makes its way into our creeks, rivers, wetlands and lakes. Some urban creeks are becoming as salty as oceans (19 000 mg/L Clˉ) and may maintain levels that are dangerous for wildlife (>120 mg/L Clˉ) year-long. Chloride levels spike during snow ice and rain events, even in the fall.
The Great Lakes Basin is not a coastal ecosystem adapted to fluctuating salt levels. Freshwater species such as salamanders, frogs and fish can’t survive in water that’s too salty and are disappearing. In groundwater dependent communities salt also ends up in the drinking water, extending the threat from species to people.
We want the Great Lakes to be Less Salty
Water health in Canada
- Use less salt: You only need a salt shaker or film cannister worth of salt rocks to clear a city sidewalk slab (1m₂).
- Shovel to remove big chunks of snow before salting.
- Know when to salt: Road salt is only effective between 0 & -7ºC