Frank Corey stands on the new Terrell Creek Dam that was reconstructed to better control waterflow and support salmon migration. Before the dam was remodeled, the water flowed out into the creek via an 8-foot dropoff on Corey’s left, and was impassable for the spawning salmon populations. (Photo by Brandy Kiger)
Despite a marked drop in temperatures Saturday morning, which left many with reddened cheeks and numb hands, residents from across Whatcom County made the trek down a service road off Aldergrove Road to get a glimpse of the improvements that will hopefully foster a restoration of chum, and eventually coho, salmon populations in the Terrell Creek watershed.
The 8.7 mile stretch of creek that drains from the 500-acre Terrell Lake and empties into Birch Bay has been barren of salmon for quite some time. Now, the Whatcom Conservation District and the Nooksack Salmon Enhancement Association (NSEA), along with many other organizations, have teamed up to find ways to make the creek a viable habitat for the hardy fish and help them find their way back upstream to the lake. “People talked about how there used to be a large population of coho in the area,” resource coordinator Frank Corey said. “So we started to look for funding. Luckily it was an appealing project, and not too hard to get.”
Funding eventually came from the National Fish and Wildlife Service and the BP Cherry Point refinery.
The project had three goals: To fix any fish passage barriers, to determine how much water was needed in Terrell Creek to support the salmon through the summer, and to install remote site incubators with native stocks of the fish.
Starting with three smolt traps in Birch Bay State Park, the NSEA trapped all out-migrating fish in the spring, carefully monitoring the number of salmon leaving the watershed. What they found was that with the exception of one sharp peak – a result of a property owner releasing salmon into the creek from his pond – the Terrell Creek population had flatlined.
It was up to the groups to find out why. Corey and NSEA teams walked the entire creek to identify potential fish passage swim barriers and found that in its current condition, the creek could not support the natural migration of the fish.
“It was like a faucet. It was either on or off,” Corey said. “And, if the water is off, salmon are not going to live.” In addition to the inconsistent waterflow caused by the Terrell Dam, there were other barriers, both natural and man-made that impeded the migration of the fish.
They included overly thick canary reed grass, inaccessible culverts, and most notably, an eight-foot drop from the top of Terrell Dam into Terrell Creek. Higher water temperatures due to the decreased stream flow, loss of deep pools and the removal of natural riparian vegetation that shades the stream didn’t help either.
Corey, along with engineers, looked at their options, and eventually decided that a new dam for Terrell Creek would be their best option. They reconstructed around 700 feet of creek bed below the dam, filling it with more than 2,300 tons of hardpan material that was compacted and graded to a one percent slope. They then covered that hardpan with 500 tons of spawning gravel, making the creek a place the salmon would be inclined to spawn.
Because the new dam was constructed with a fish passage and easy access in mind, the project also allowed for a bypass system that could be used to lower lake levels and moderate winter flood flow without disrupting the habitat.
Once all the provisions were in place to ensure that the salmon could survive, project coordinators began reintroducing a native stock of chum to the creek using remote site incubators. Rachel Vasak, director of the NSEA, noted that volunteers who monitor the salmon remote site incubators are key to the program’s success. “It’s so critical to have volunteers. We have 5,000 fish to babysit, and we’re responsible for their safekeeping.”
In their restoration efforts, NSEA decided that it would be best to start a reintroduction program with chum salmon because their spawn hatch out of the gravel and do not require the extensive 18 months of growing time in freshwater that cohos do. The adults swim upstream and spawn in October, by February the eggs are ready to hatch and then the hatchlings make their way out to the sea.
They’ve been working for six years now to bring the chum back to the area and restore salmon to the watershed. With some success under their belt, they can now start thinking about reintroducing coho to the area.
While they are not yet sure what kind of population Terrell Creek can support, Vasak said that she’s simply trying to achieve a population that will be self-sustaining. “Every watershed is different,” she said. “Before we started putting our footprint around here, these streams were full of fish.”
She also added that the changes made to the creek to improve fish passage do more than just offer the chance for a salmon population to once again thrive in the watershed. They also contribute to improving the overall water quality of Terrell Creek and its tributaries. “The [salmon] are an indicator species. Our hope is that if we improve the water quality along the creek, we’ll improve the water quality in the watershed. It won’t fix everything, but it’s a piece of the puzzle,” Vasak said.