Water district officials on Salt Spring are hopeful provincial funds to raise a weir at St. Mary Lake can also be used to bring about an ecological compromise — protecting competing interests of furry and finned wildlife living at Duck Creek.
The North Salt Spring Waterworks District (NSSWD) received approval for an unexpected $10 million in funding from the B.C. government last year to raise the weir at the island’s largest lake, to both increase water storage capacity there and to better sustain the required environmental water flow into the creek — where salmon annually come to spawn.
While the storage capacity issue is practically self-explanatory, a nuance surrounding protecting the environmental water flow was again brought to light this month, according to NSSWD operations director Ryan Moray, with the return of a “little furry friend.”
“The beaver has returned,” said Moray at the district’s meeting Thursday, May 29, “and ironically has built a dam in a very similar spot to where he did two years ago.”
The district has once again applied for a permit to remove the beaver’s handiwork, since it directly interferes with their ability to deliver the mandated water flow for salmon in Duck Creek. But trustees and staff imagine a future where they might be able to let the animal go about its business in peace — a plan that hinges, in part, on determining whether the flow they’re currently sending downstream is the right one.
Board chair Brian Pyper said the district is mandated to provide 8.9 litres of water every second into Duck Creek year-round — a number that’s hardly noticeable, supply-wise, during the winter and shoulder seasons.
“But that’s also what we have to provide during the summer and the early fall,” said Pyper. “When we look at the entire consumption, on average, of both Maxwell and St. Mary lakes, we’re at about 17 litres per second — so roughly 50 per cent of our entire consumption is mandated for summer flow.”
There’s certainly a number that’s too low, Pyper said, recalling a drought summer where flows had fallen to less than one litre per second.
“The streams were drying out,” said Pyper, “and the temperatures were rising.”
Pyper said he had joined salmon enhancement society members and others who “went out with buckets” to collect and relocate fish. After the crisis, he said, it had been satisfying to see how as little as two litres per second had brought conditions at Duck Creek to “something that looked healthy” for the ecosystem. The possibility that salmon in the creek could be reliably sustained with less water was something the district had subsequently put to federal and provincial officials.
“What the DFO folks indicated to us was that a separate study could be required,” said Pyper. “We’re trying to see if we can get an answer on this within the budget of the weir funds — because it’s a key component of the [weir] design.”
Moray said one of the design options would include a “cohabitation” plan for both beaver and fish.
“That one has a larger dedicated pipe that could accommodate both fish passage and environmental flow needs,” said Moray, “and then keep that clear of beaver activity, potentially letting the beaver utilize the existing channel for his activities.”
Pyper said the biologist consultant had suggested the other solution was to trap and relocate the beavers, leaving the channel open for fish passage and flows. The board wanted to wait for staff to hear more from provincial officials before making that decision.
“We’re looking at all the options,” said Pyper.