This story is taken from Sacbee / Our Region / Environment
mweiser@sacbee.com
Published Monday, Jun. 22, 2009
The American River once hosted thousands of steelhead migrating upstream from the ocean in three separate runs. Today it's down to just two runs of a few hundred fish.
The Sacramento was the only river in western North America with four salmon runs. They numbered in the millions – so numerous that American Indians and settlers could catch a salmon dinner with their bare hands. Now one run is gone, and two are endangered. The fourth could join them soon.
Restoring a fragment of that spectacle to the Central Valley is the goal of rules proposed by the National Marine Fisheries Service. The service wants, among other things, restoration of winter- and spring-run salmon above Shasta Dam on the Sacramento River, and steelhead above Folsom Dam on the American River.
Combined, the fish transit order is considered the biggest of its kind in U.S. history.
Making it happen presents huge financial and engineering challenges. Costs could exceed $1 billion at a minimum – more than 10 times the original construction cost of both dams.
"It's pretty substantial, the amount of work that's required," said Mike Chotkowski, regional environmental officer at the U.S. Bureau of Reclamation, which operates the dams. "We still haven't even determined whether it's feasible."
The fisheries service says that without restoring access upstream, it's likely the three fish species will go extinct. Climate change means it will be harder to maintain cold-water habitat below the dams, so they must have access to better habitat.
"The fish are at that jeopardy point where it's important for us to take immediate steps," said Howard Brown, Sacramento River basin chief for the fisheries service.
The rules proposed this month, called a biological opinion, were developed in response to a lawsuit brought by environmental groups. Federal Judge Oliver Wanger agreed with their claim that prior rules, which had no fish passage requirement, did not prevent extinction.
The ruling raised anxiety among California water managers. Thirty agencies sued last week, alleging that the fisheries service didn't follow procedure in adopting the rules.
Other experts argue there are cheaper ways to rescue the salmon populations.
Among them is the volunteer group Save Auburn Ravine Salmon and Steelhead. It has worked quietly over the past year to remove small obstructions on Auburn Ravine, a little-known tributary of the Sacramento River.
The natural ravine flows with spring water and sewage treatment outflows starting in Auburn.
Accounts as recent as the 1960s show that the ravine once hosted robust fish runs, said John Rabe, a member of the group's board.
Four adult salmon were observed in the ravine last winter. The group expects hundreds next winter and plans a salmon festival in Lincoln to welcome them back.
Rabe said 600 small creeks between Modesto and Redding also could be restored – at far less cost than fixing the big dams.
"Don't waste time and money on the dams. Spend it on the creeks," he said. "That would open literally thousands of miles of spawning, which would make a huge, huge difference."
The federal rules don't specify how salmon and steelhead should be moved around the dams. Instead they require studies, starting in December, to find the best solution that can be in place by 2020.
By March 2012, water agencies must begin moving fish around the dams on a trial basis. This will probably be done by loading fish into trucks.
Experts say moving fish around Folsom and Shasta dams is a job as big as the dams themselves. Shasta, completed in 1945, stands 602 feet high. Folsom was finished in 1956 and soars to 340 feet tall.
They were built without any means to pass fish upstream, and each has a smaller dam downstream to regulate flows: Nimbus on the American, Keswick on the Sacramento.
Distance and elevation required to move fish upstream may eliminate the option of a traditional fish ladder at both dams, said Alex Haro, a research ecologist at the U.S. Geological Survey fish laboratory in Turners Falls, Mass.
Fish might not be able to cover the distances up and around the dams in a single day. As night falls, if fish are partway up a ladder, their instinct is to stop and rest, so they give up and turn around.
An alternative is a fish lift – essentially an elevator to raise fish straight up the face of the dam in a container. But like a fish ladder, it has limitations. One is that the fish then are released in a stagnant reservoir, without flows to guide them to spawning habitat.
Because of this, trucking and hauling fish could become the permanent solution.
In short, salmon and steelhead blocked from their historic habitat for decades instead could be driven home like commuters on a bus.
Fishery managers typically don't like truck-and-haul operations because fish survival in the past has been poor: Roughly half of the fish sometimes die from stress, oxygen loss or high temperatures.
But Kozmo Bates, a fish passage expert in Olympia, Wash., said survival is typically better than 90 percent in modern trap-and-haul operations.
"There's a certain protocol that makes it safe for the fish," he said. "I can't say it's 100 percent, but in new, contemporary facilities I've rarely heard of any problems with the fish, and when there are problems they get fixed quickly."
Sounds easy, but it is wrong to assume trucking fish is a cheap fix, experts said.
One reason: The collection facility at the base of the dam is essentially the same whether it serves a fish ladder or a trucking operation.
The fish must be directed from the river below the dam into a confined space. It's against their nature to do that, so they must be tricked with precise flows and temperatures, and a perfectly designed containment space.
This comes with a cost to water supplies. Dam operators must give up 3 percent to 5 percent of the water stored in the reservoir to create flows for fish passage through the containment structure, Haro said.
Also, juvenile fish have to be moved back below the dam after they've spawned. This requires a different collection system above the dam, one that ensures young salmon or steelhead don't get lost in the massive reservoir or eaten by predators such as bass.
One example of a modern downstream passage structure was built at Baker Lake in Washington state in 2008. It consists of nets spanning the reservoir near the dam, which direct fish into channels, and then mobile tanks mounted on floating barges.
Tanks are hoisted onto trucks, which deliver fish to ponds below the dam, where they acclimate to downstream conditions for a day or two before being released.
Bates estimates both upstream and downstream passage for truck-and-haul systems could cost $500 million each for Shasta and Folsom.
That's conservative, because each lake may need multiple downstream collection facilities, since each has multiple tributaries feeding the lake that may hold spawning fish.
"You have high dams, you've got predators in the reservoirs, you've got reservoirs that fluctuate greatly, and you have big rivers, too," Bates said. "You have four things there, and each one quadruples whatever price you start with."
The new rules, however, do provide something of an escape clause.
If a panel of water agencies and fish experts decides fish passage around the dams isn't feasible, salmon and steelhead must be restored elsewhere. That would turn the focus back to the Central Valley's many neglected creeks.
That's what John Rabe and the Auburn Ravine group are working on – a solution he said is "more realistic and a lot less expensive."
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Call The Bee's Matt Weiser, (916) 321-1264.
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