ALDER LAKE – Logs and other woody debris delivered during winter storms to the reservoir behind Alder Dam are a safety hazard for boaters and a headache for Tacoma Power maintenance crews in this popular recreation area near Mount Rainier.
But that same assortment of wood is a blessing for salmon habitat restoration projects in the tributaries of the Nisqually River, including Ohop Creek near Eatonville.
So the Tacoma utility and partners in a major Ohop Creek restoration project teamed up last week to move about 100 logs from Alder Lake several miles down the river valley to ground zero of the Ohop Creek project.
They put their trust in the team of Eatonville contractor Max Swick and log truck driver John Zizer, who carefully negotiated a loaded truck across the narrow causeway atop the 1,500-foot-long dam, flanked by the lake on one side and the Nisqually River 330 feet below the dam on the other side.
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With just inches to spare, eight loads of logs snaked across the dam and now await use in what is the most ambitious stream restoration project in the Nisqually River watershed.
Beginning in August, a 0.6 mile stretch of the creek, which was straightened and ditched by farmers for irrigation and flood control in the early 1900s, will be reshaped into a 1-mile streambed that meanders through 90 acres of revegetated wetland habitat. The new stream will be dug this year and the logs will be placed in the streambed this summer. Then water will be allowed to flow there next year at a cost of $2.2 million, said Kim Gridley, project manager for the South Puget Sound Salmon Enhancement Group, one of the Nisqually tribe’s many partners on the Ohop project.
It’s part of a long-range project that could eventually turn 4.3 miles of ditched stream channel back into 6 miles of more natural, fish-friendly stream flowing through the narrow, lush Ohop Valley.
Restoring creeks like the Ohop is important because it’s one of only two tributaries to the Nisqually River that produce chinook salmon, which are listed as threatened under the federal Endangered Species Act.
“If some catastrophic event – for example, a devastating flood – were to wipe out the entire population of chinook along the main stem of the river, salmon from Ohop Creek would be able to repopulate the rest of the river,” said Jeanette Dorner, salmon recovery program manager for the Nisqually tribe. “By having separate populations in different rivers and creeks in the same watershed, you strengthen the entire population.”
The rebuilt, broader stream will provide better winter habitat for young chinook and coho salmon, as well as improved habitat for steelhead, pink salmon and cutthroat trout.
All the species will benefit from the man-made logjams, which are places where young fish can feed and rest, said Florian Leischner, a tribal salmon recovery biologist.
Strategically placed logs also slow down stream flows, making it easier for adult salmon to migrate, he said.
The project has taken years to plan, partly because it takes the cooperation of several property owners in the narrow, lush valley.
People have been concerned about increased flooding and limiting livestock access in the valley as more of it converts to wetlands, Gridley said.
“So we moved the project further downstream to reduce the risk of upstream flooding,” she said. The project begins on a farm purchased by the Nisqually Land Trust, a willing partner.
Swick, a longtime Eatonville area resident, offered this assessment of community attitudes on the Ohop project:
“I think more and more people are aware of the need for projects like this,” he said.
Tacoma Power provides log debris collected from behind its hydroelectric dam reservoirs to several stream habitat restoration projects in southwest Washington free of charge, said Tacoma Power biologist Mark Wicke.
Typically, logs and other woody debris flush into the reservoirs during the rainy season, wash up on the shoreline that time of year when the reservoirs are drawn down, then start to refloat and cause a nuisance to boaters and other recreational users in the late spring and summer when the reservoirs are allowed to refill for recreation, he said.
“In past years, we used to have to burn a lot of the wood debris,” Wicke said. “We’d rather put it to a good use like this.”
Most of the logs headed for the Ohop project arrived in Alder Lake during the major December 2006 storm, he said.
It took eight Tacoma Power employees two months working 12-hour days to clean up the mess, which totaled 100,000 cubic yards of wood debris, Wicke said.
The common method for cleaning the reservoirs of logs is to build a log boom, connect each end to a boat, then sweep up the debris, allowing it to collect behind the boom before it’s deposited above the shoreline.