Erynn Du / Staff Reporter
Winter is here in British Columbia, and that means people are dumping road salt on their driveways. But what isn’t common knowledge is how it effects salmon. In the CBC article, “Road salt runoff has conservationist worried about salmon,” John Templeton, chair of the Stoney Creek Environment Committee explains that excessive levels of salt in salmon habitats can kill off the salmon eggs and interfere with their growth.
With dangerously low populations of salmon returning, knowing how road salt impacts salmon is essential to preserving their growth.
Every year the city of Vancouver uses 3000 tons of road salt in order to upkeep road safety. There is no doubt that road salt is needed for safety, but what about the streams?
A new study by researchers from UBC collaborating with local hatcheries are trying to learn more. When people pour salt on the roads, the ice and snow eventually melt, washing the road salt into untreated storm drains which lead into the streams. “There are federal and provincial regulations that set maximum salt levels in streams, but these levels are not routinely monitored,” wrote UBC researcher Dr. Chris Wood.
Earlier research has already shown that high salt levels in freshwater streams lead to increased deformities and mortality for salmon. “Even though adult salmon live in salt water, they grow up in fresh. When they’re ready for salt water, their whole body has to change to adapt,” wrote UBC researcher Dr. Patricia Shlute.
Even though road salt cannot be eliminated due to safety reasons, there are ways to minimize the damage. The most obvious is to use road salt properly. From the CBC article, “Researchers investigate impact of road salt on salmon,” Wood says, “We’re not saying that salt is all bad — salt is good in many ways. It makes our lives safer when we salt roads — but we do think there is a tendency to overuse salt and not apply it in the most thoughtful manner.”
According to the Ottawa Riverkeeper website, one meter of sidewalk only requires two tablespoons of road salt. The salt should be sprinkled evenly, not in clumps. It is also recommended to buy pet-friendly salts, which are also safer for salmon too. Sand is also a cost-effective method. However, it doesn’t work as a deicer, rather the sand provides traction on the ice. A rather new alternative some cities like Toronto and Calgary are using is sugar beet juice. The juice lowers the freezing temperature and works in freezing temperatures much lower than salt. Unfortunately, the sugar in the beet juice increases germs, and when melted into streams, can reduce the oxygen in water. Though there is an environmental cost to every alternative, some are better than others. Moving forward, it is important to be mindful of what we are pouring on the ground, as it all ends up in the streams where the salmon spawn.
Sources:
Researchers investigate impact of road salt on salmon | CBC News
Road salt runoff has conservationist worried about salmon | CBC News
Calgary expands use of beet juice to de-ice roads | CBC News