Annual dredging of the Snohomish River will be completed earlier than usual because of new federal protections for salmon. The Army Corps of...

Annual dredging of the Snohomish River will be completed earlier than usual because of new federal protections for salmon.

The Army Corps of Engineers removes sandy material each year in a six-mile stretch of the Snohomish River, starting at its mouth, from one of two collector basins on the river’s bottom.

In the past, the work was usually completed around February. But because of new regulations to protect salmon in Washington, Oregon and Northern California, the work must be completed by Jan. 2, when the rules will go into effect, said Patricia Miller, the corps’ project manager for the dredging.

As a result, a contractor has been working 24 hours a day, six days a week since Dec. 6 to remove 200,000 cubic yards of silt from the upstream collector basin. The work is usually spread out over a longer period.

“Because of the new regulations, our permit for doing this work expires at the end of the year,” Miller said.

The corps will work with the National Oceanic and Atmospheric Administration, which regulates habitat in federal waters, to determine a dredging schedule for next year, Miller said.

The corps plans to dredge the downstream collector basin at the end of 2006, she said, keeping with the alternate-year schedule of dredging the river’s upstream and downstream basins.

The new regulations will determine when that work can be done without harming salmon. In the Puget Sound area, chinook salmon are protected under the federal Endangered Species Act.

The corps maintains the two collector basins, which are about 30 feet deep, because the last portion of the Snohomish River is a federal navigation channel. Typically, the river is about 8 feet deep near the upstream collector and about 15 feet near the downstream collector.

The silt collected this year will be dumped at an approved spot in Port Gardner Bay, Miller said.

Often, the material is reused. In the past, the silt has been used to reinforce protective berms at Jetty Island and to cap Superfund sites around the U.S., and as a base material in road projects. There have been no takers for the silt being collected this month, though.

The Port of Everett, which dredges areas near its marinas, says it relies on the corps to dredge the lower stretch of the Snohomish River because silt buildup would prevent larger boats from navigating the river.

“Also, when we go to dredge our marina facilities, there would be more for us to dredge, making it more expensive for us in the long run,” said Graham Anderson, a senior planner for the Port.

Christopher Schwarzen: 425-783-0577 or cschwarzen@seattletimes.com