As young, winter-run Chinook salmon swim from where they were born below Shasta and Keswick dams, they’re forced through levees in Battle Creek. Before those levees, Battle Creek would’ve been used as an area for those salmon to rest, feed and grow stronger before embarking into the ocean. 

Winter-run Chinook salmon were listed as an endangered species in 1994. Its population has been declining dramatically since the 1970s, according to the California Department of Fish and Wildlife. The salmon are threatened by warming waters and dams, making it more difficult for them to reach the colder waters closer to the snowmelt to spawn.  

Chad Praetorius, a fisheries biologist, said it’s a “death by a thousand cuts.” 

The effort in Battle Creek is being led by Chico State’s North State Planning and Development Collective. Recently, the California Wildlife Conservation Board granted the Collective $1.85 million. This money will go toward mitigating “… threats to juvenile salmon by reversing years of habitat fragmentation, floodplain disconnection and diminished nutrients,” a press release from Chico State stated. 

The project in Battle Creek is a small slice of the work being done throughout the salmon’s journey to help return the dwindling population. 

Rebekah Casey is the assistant director of the Collective and project manager for habitat restoration, which involves work such as removing levees to create flood plains for salmon to rest, feed and hide from predators.

The removal of those levees will slow down the speed that water flows through Battle Creek, allowing for the salmon to spend more time in the area to grow stronger before embarking downstream and, ultimately, into the ocean. 

Casey said that this grant money helps them finish previous work. In 2021, the Collective received a $10 million federal grant, which funded the investigation and planning for a restoration project; there wasn’t enough left over for construction and stewardship. 

“They (the Collective) came up with a design to remove about 3,000 feet of levee,” Casey said. These levees were rocks put into the channel to prevent overflow, preserving agricultural space. Now, the Collective is seeking to remove those levees to let the river create flood plains for the salmon during high flows. 

“It’s like a pilot gas station for a fish. They pull over, they get a snack, hangout, and relax to chill during high flows,” Praetorius said. 

Casey explained that research has been showing that the longer young salmon stay in the system before entering the ocean, the longer those salmon survive.  

With those levees gone, “They can go up into the flooded grass, and they have cover in the flooded grass and they feel free to just eat,” he said. “As that water pulls away from the floodplain and back into that creek, now they’re fatter and bigger.” 

They’re ready to go back on their timetable, not the levee’s timetable.”

Those salmon stay in the ocean for one to four years before heading back up into the Sacramento River — bringing ocean nutrients, such as nitrogen and phosphorus, along with them.

The nutrients and biomass brought to and from the ocean are critical for riparian areas, Casey said. 

“In the salmon-bearing streams, they found that there were nutrients that come back with salmon in the redwood trees,” Casey said. “The birds get them, the animals eat them. You end up with nutrients from the ocean that you just can’t grow here.” 

The nutrients delivered by salmon carcasses and waste enrich the soil along the banks of the river, creating more resilient ecosystems. With less salmon, fewer of those nutrients are used by the ecosystems that host an abundance of life. 

That’s why Praetorius called this project “beyond a dual purpose.” Those nutrients that fed the ecosystems helped the river “meander,” instead of what it currently does, which is continuously dig downward. 

“Most of the projects we’ve done have been to restore that meander in the river, but this time we’re removing the rock to allow it (the river) to do its job,” Casey said. “We’re creating a channel, but really we’re giving it its power back.” 

The construction will take about nine months, Casey said. Then, native species will be planted in the area. She said that the habitat restoration will contribute to relatively fast results.. 

“There just isn’t enough habitat, so when there is habitat there, they start to utilize it,” she said. 

Much of this area was tribal land, and as the Collective begins restoration, they’ll continue working with the Tribal Office at Chico State in case they come across cultural artifacts.  

“There’s a lot of tribes in that area, and if we find something, we definitely want them to be a part of the solution finding,” she said. 

Chris Hutton can be reached at [email protected]