A UBC-led project aiming to protect B.C.'s declining salmon population by identifying and reducing toxic road runoff, has received a significant financial boost.
The team has been awarded a $1.8 million grant from the provincial and federal governments through the second phase of the B.C. Salmon Restoration and Innovation Fund.
It was one of 58 B.C. projects splitting $86 million in funding for salmon protection and habitat restoration.
The researchers have linked 6PPD-quinone, a toxic chemical shed by car tire, to salmon deaths in Washington state, and are investigating similar connections here in B.C.
“When it serves its function in the tires, it's protecting the tires from oxidation, it forms a byproduct that's acutely toxic to salmon and particularly coho salmon,” explained Rachel Scholes, an assistant professor of civil engineering at UBC. “Any time it runs off our roads when it rains into creeks and streams it can cause toxicity … at very low concentrations it actually causes coho mortality.”
The UBC team is now working to identify potential toxic hotspots in the province so they can mitigate the chemical's deadly effects.
Postdoctoral researcher Timothy Rodgers said the team is sampling water at 20 salmon-bearing streams across Metro Vancouver, with a particular focus on North Vancouver and Surrey. Researchers test the water before, during and after rainfalls to measure levels of the compound in water.
“Everywhere the roads are interacting with watersheds is a place where there is at least some risk,” he said. “They go from very, very low before the storm, then they jump up … by like 60 times. We know we are seeing levels in the stream that are above the lethal concentration for 50 per cent of the salmon … and those are staying elevated for at least a couple of hours.”
“Together these projects will inform long-term water and salmon stewardship planning and provide valuable information on watersheds and trends that are critical to wild salmon populations,” federal Fisheries and Oceans Minister Diane Lebouthillier said Thursday of the B.C. Salmon Restoration and Innovation Fund grants.
“We know that restoration is critical to this. We can't just protect, we need to restore those critical places where salmon need to come back and spawn,” added B.C. Water, Land and Resource Stewardship Minister Nathan Cullen.
In the UBC project, the money will be used to build on previous research and support field studies on urban creeks during rainy weather to understand actual salmon exposure.
The team's research is aimed at the creation of “rain gardens” and other green infrastructure capable of filtering and containing 6PPD-quinone, preventing it from reaching at-risk salmon habitat.
“What we've found is that if the water that runs off of the roads carrying this chemical, if it passes through a rain garden or bio-retention system, if it filters through soil, a lot of the chemical gets removed,” Scholes said. “So it really protects salmon if we can install these kinds of rain gardens between busy roads and creeks and streams that have salmon populations.”
The team is working with the cities of Surrey and Vancouver to look at retention ponds to capture road runoff, and to explore how rain garden design could make them better at filtering out 6PPD-quinone.
In November, the U.S. Environmental Protection Agency said it was launching a regulatory review into the chemical which could one day see it banned.
– With files from Paul Johnson
