A leg up for salmon
Construction has begun on a new fish ladder around the dam on Bear Creek at the Oak Street Bridge in Ashland. The $1.7 million project is expected to be completed by Oct. 15.
The diversion dam, built in 1920, helps apportion water flows to fish and to irrigators in the Talent Irrigation District, said fish biologist Mick Jennings, who was working on the dam Tuesday.
The present fish ladder was modified 17 years ago, but the National Marine Fisheries Service in 2008 established criteria for fish passages, and this fish ladder doesn’t measure up, said David Walsh, spokesman for the U.S. Bureau of Reclamation in Boise, Idaho.
Reclamation is overseeing the project, which is being done by Northbank Civil and Marine of Vancouver, Wash.
The fish ladder, now on the south bank of Bear Creek, is being moved to the north bank in two stages that will allow fish to use one, then the other, without interruption, said Jennings.
“This will be a better fish ladder,” he said. “Right now, the steelhead and coho (salmon) are having difficulty finding the entry to the ladder so they can get upstream and spawn. Coho have special protection and have more difficulty jumping. They’re not great leapers.”
The new ladder complies with the Rogue River Basin Project’s Biological Opinion of 2012, which requires the Bureau of Reclamation to establish fish passage for Southern Oregon and Northern California coho for all of Bear Creek to the upper reaches of its tributaries, said a news release from Walsh.
The operation of the diversion dam will be controlled by an Obermeyer bladder, which reacts to water flow by filling with air, so it can raise or lower the gate, apportioning water to fish and irrigation, said Elizabeth Heether, Bureau of Reclamation environmental protection manager in Yakima, Wash.
“It’s a conservation project for coho. We’re hoping for more coho into the upper reaches of Bear Creek tributaries,” said Heether. “It modifies the dam crest and improves flow control and sediment movement.
“It’s a system to provide computer support, analyzing data at TID. It provides better attraction flow to help fish find the ladder. It’s a technical project with a lot of benefit for getting passage over the dam. In irrigation season (summer), TID gets the same amount of water and fish get a more reliable flow.”
Northbank Project Manager Evan Grass, working on the project last week, said, “Now, it doesn’t flow right. Fish are not getting up there right. … When we’re done, it will have a bigger pool, wider passage and better flows for the fish. In summer, when we need more water in the TID canal, the Obermeyer will pop up and do that.”
Walsh said the new ladder was to be poured and the old ladder demolished this week. The Obermeyer is slated for installation Aug. 18.
John Darling is a freelance writer living in Ashland. Email him at firstname.lastname@example.org.