Record Spring Chinook Return At Willamette Valley’s Fall Creek Dam, Reservoir Drawdown To Move Juveniles A Factor

The U.S. Army Corps of Engineers report a record return of spring chinook salmon this year at Fall Creek Dam.

According to officials, more than 800 spring chinook salmon returned this year.

Fall Creek Dam is at river mile 7.2 on Fall Creek, a tributary of the Willamette River, about 20 miles southeast of Eugene, Ore. It is a rockfill structure with a gated concrete spillway and outlet works for regulating lake levels. Fall Creek was completed in 1966 at a cost of $22 million.

Fall Creek Dam works in coordination with Lookout Point and Hills Creek dams to provide flood risk management, water quality improvement, irrigation, recreation, and habitat for fish and wildlife. During flood season, the dams hold back water to regulate downstream flows. Fall Creek Lake provides 115,100 acre-feet of storage and controls runoff from 184 square miles of drainage area.

Greg Taylor, a fisheries biologist with the Corps’ Portland District, said this year’s spring chinook return number is more than double the 10-year average return rate, which is about 350 fish, and higher than the pre-dam estimate of 600 fish for this subbasin.

“The overall return to the Willamette Basin is not strong, so seeing such a high return came as a welcome surprise,” Taylor said.

Reservoir drawdowns are a contributing factor in this success story, he said.

“The full draw-down of the reservoir behind Fall Creek Dam to the streambed passes more juvenile fish downstream at a higher survival rate than previous operations.” said Taylor. “The key to getting adult salmon back is getting more juvenile fish safely downstream.”

The operation has additional benefits for young salmon that will live in the reservoir next year by reducing the numbers of nonnative fish that predate on or compete with these fish for food in the reservoir.

“This type of success is a great model for what we might be able to do at other projects,” said Taylor.

Corps biologists operate the Fall Creek Adult Fish Facility, located at the base of the dam, and work with partners from the Oregon Department of Fish and Wildlife and the National Marine Fisheries Service to improve fish numbers within the basin.

At the facility, biologists collect returning salmon and record data about them such as size, weight, gender, whether they are hatchery or wild, and overall health. Then the fish are safely transported by truck upstream to spawn.

To learn more about Fall Creek and Corps’ draw-down efforts visit:

www.nwp.usace.army.mil/willamette/fall-creek/drawdown/

Also see:

— CBB, Sept. 22, 2017, “FALL CREEK DAM (MID-WILLAMETTE) GETS NEW FISH COLLECTION FACILITY TO MEET BIOP REQUIREMENTS” https://www.cbbulletin.com/fall-creek-dam-mid-willamette-gets-new-fish-collection-facility-to-meet-biop-requirements/

— CBB, August 19, 2020, FEDERAL JUDGE RULES CORPS NOT MOVING FAST ENOUGH TO HALT CONTINUED DECLINE OF ESA-LISTED UPPER WILLAMETTE RIVER WILD SPRING CHINOOK/STEELHEAD; “SIGNIFICANT MEASURES NEVER CARRIED OUT’ https://www.cbbulletin.com/federal-judge-rules-corps-not-moving-fast-enough-to-halt-continued-decline-of-esa-listed-upper-willamette-river-wild-spring-chinook-steelhead-significant-measures-never-carried-out/

— CBB,  Feb. 6, 2015, UPGRADES AT OREGON’S FOSTER DAM (SOUTH SANTIAM) FISH PASSAGE FACILITY AIMED AT ESA-LISTED SALMONIDS https://www.cbbulletin.com/upgrades-at-oregons-foster-dam-south-santiam-fish-passage-facility-aimed-at-esa-listed-salmonids/

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