The Nooksack River registered some of its highest flood levels ever in the recent flooding that authorities now say caused as much as $50 million in damages. But that doesn’t fully account for the impact on salmon runs and habitat restoration work managed by the Nooksack Indian Tribe. And the Lummi Nation listed major concerns about flooding impacts on its two salmon hatcheries, as well as likely devastation on juvenile fish and redds in the Nooksack Basin.
The Nooksack River, which loops around Bellingham and the North Cascades in northwest Washington, provides habitat for all five species of Pacific salmon. Historically, the Nooksack tribe has depended heavily on early chinook runs. Those have been the focus of recent restoration work.
Just this past summer, the tribe finished installing more than 100 engineered logjams in the north fork of the river, to cool and slow the water for these critical salmon runs.
Habitat program manager Treva Coe says they’re worried about the impact of what was likely record-breaking high water on all of that work.
“But flooding is common, and we design these to be stable in 100-year flood and to be resilient to changes — channel changes, the channel moving,” Coe said, “but sometimes we’ll see some damage.”
She says both of the early chinook runs have hatchery programs that are sustaining them, and it’s a good insurance program moving forward. But it’s far from ideal.
“We're really trying to do what we can to restore the habitat so they could be naturally sustaining and not have to be sustained in hatcheries,” she said.
And that’s why habitat restoration is so critical.
“We've built hundreds of these structures, and for the most part, they've remained stable and intact,” she said. But all bets are odd when the water comes as high and fast as it did on Nov. 14.
“We’re eager to get out and see how they fared,” she said.
It will likely take weeks before they know what happened to the logjams because flooding remains in many areas and is preventing access on the ground. An early flyover of the south fork by helicopter revealed no obvious losses.
But along with any immediate physical devastation of these new structures, there’s concern about impacts on juvenile fish and eggs in the riverbeds, planted in salmon nests known as redds. Damage to them won’t be fully understood until the young fish and hatchlings are expected to return as adults, several years from now.
“It’s inevitable that nearly every single chinook and pink salmon redd in the Nooksack Basin was destroyed from the extreme flood event,” wrote Tom Chance, the Lummi tribe's salmon enhancement manager, in an email about the flood damage.
He said that tribe’s two hatcheries were “able to squeak through with no severe issues,” though they were greatly impacted with temporarily clogged intakes because of sand and gravel brought in by the floodwaters. Still, he said, the recent flooding show how critical those hatchery program are.
“Without these hatchery programs, we may be teetering on the brink of the extinction of natural-origin Nooksack chinook after a year like this,” he wrote.
