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Rocky Reach fish bypass system creates conflict

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WENATCHEE, Wash. - The right kind of fish bypass system to use at a dam is as difficult for humans to figure out as it is for salmon to negotiate.

In the Columbia basin, water hydraulics, volume and flow rate as well as dam, spillway and tail race construction vary from dam to dam.

Add to these physical differences the Endangered Species Act (ESA), policies from the Bonneville Power Administration and various Public Utility District (PUDs), the National Marine Fisheries Commission, the U.S. Fish and Wildlife Service, tribes, the Columbia River Inter-tribal Fish Commission, public comment, politics, profit and environmental activism and you've got a real logistics nightmare.

Fish-friendly dams are a contradiction in terms. Implementing bypass systems is just as contrary.

Everybody involved with salmon restoration has an agenda. Bonneville Power Administration and the PUDs want to generate power as profitably as possible while meeting ESA requirements. Tribes want to be able to fish in their usual and accustomed places, conduct their ceremonies, run their fishing businesses and feed their families.

Politicians want everybody to be happy. They want constituents to feel the environment is being served while business and industry are being supported at the same time.

Agencies whose job it is to implement environmental policies want to develop comprehensive plans that work. They want their programs and budgets to grow.

On an individual level, many people in all these organizations have a deep interest in saving salmon for the salmon's sake. Left to personal preferences, they would like to see the rivers run and the salmon flourish.

But the public's all-consuming need for electrical power, plus the profit motive of the utilities that serve them, make direct spill the least cost-effective method of facilitating salmon passage. More often than not, dam bypass systems become a study in compromise between the bottom line and environmental stewardship.

The Rocky Reach dam in the Chelan Public Utilities District of the mid-Columbia River is a good example.

Depending on which direction salmon are migrating, Rocky Reach Dam is either hurdle two on the way to the ocean or hurdle eight on the way back. Depending on who you talk to, the average direct and indirect mortality rates at Rocky Reach for fish headed downstream is 5 to 10 percent.

Not all dams are created equal as far as fish mortality is concerned. A lot depends on whether the dam is equipped with intake deflection screens, the type, size and speed of turbines used to generate power or whether fish are spilled over the dam at high flow rates or have to negotiate other bypass systems around the dam.

Direct mortality occurs when a fish is killed immediately, in the process of negotiating the dam. Indirect mortality occurs when fish are de-scaled swimming past the deflectors or stunned by the turbine blades and die later.

And then there is predation. Birds and other predators learn where fish are siphoned back into the river having negotiated a spillway or bypass. If current flows are sluggish in these areas, salmon smolts are easy pickings.

In addition, because fish often hesitate at dams for as much as a week during migration, their journey may conceivably stretch out two months longer than a normal, unimpeded passage would take. Of those that survive, many may be in a weakened state by the time they head to sea.

In response to these problems and under the mandate of the Endangered Species Act, dam operations along the Columbia are required to keep mortality rates as low as possible.

Section 10 of the ESA allows commercial operations to function while permitting a certain "take" or kill of endangered fish. Each dam operation is licensed and monitored by the National Marine Fisheries Service and the Federal Energy Regulatory Commission (FERC). Rocky Reach is up for re-licensing by 2006.

Officials at Chelan PUD, which operates the dam, hopes an ambitious salmon bypass system they have been working on since 1994 will satisfy its re-licensing requirements as far as the ESA and FERC are concerned.

Under guidelines of a Habitat Conservation Plan structured in 1994 by Chelan PUD, NMFS and Washington Fish and Wildlife Service, the utility is shooting for a 95 percent overall survival rate for salmon negotiating Rocky Reach Dam.

To arrive at that low a mortality rate, engineers have used a combination of tools, including intake deflector screens, a 4,600-foot, $20 million bypass tube, plus a certain amount of spill over the dam for sockeye every season.

"The last couple of years we've been conducting some pilot survival studies and we've got indications that we're very close to meeting Habitat Conservation Plan goals," says Brett Bickford, senior civil engineer project manager for the Rocky Reach fish bypass system. "We decided to stop prototyping and go ahead ... and make a final system."

But the Yakama Nation and the Columbia River Inter-tribal Fish Commission disagree with Chelan PUD's plan on several counts.

First they object to use of the Habitat Conservation Plan as a guideline because no Environmental Impact Statement has been released and there is no signed agreement between Chelan PUD, NMFS, the Department of Fish and Wildlife and the state formally implementing the plan.

"I think all of us, whether it's state, federal or tribal agencies, are very concerned that they are proceeding with this project because there are criteria for this project that aren't meeting standards in terms of engineering and velocity criteria," says Bob Heinith, a hydrology expert with CRITFC. "Moreover, the fact is that it's a system that is not showing very much promise in terms of the number of fish it's guiding to it."

In the past, poor performance of intake deflection screens at the dam lead Chelan PUD engineers to almost scrap their use.

"We've got scientific review by an independent scientific advisory board and they basically said we shouldn't put in any more screen systems ... because the evidence is that screen systems de-scale fish; they select one stock versus another and there appears to be significant delayed mortality directly related to the screen systems," Heinith says.

Heinith and Bob Rose, assistant to the environmental manager for the Yakama Nation, say they believe current plans at Rocky Reach promise little improvement over past performance. They say because of the configuration of the dam, the best solution for salmon passage is either natural spill or constructing a sluiceway through the face of the dam at a point called the Cul de Sac.

"You're probably going to get some of the best fish passage in the river if you do that," Heinith says.

Chuck Pevan, fish and wildlife supervisor for Chelan PUD, says a sluiceway constructed from the Cul de Sac would be so enormous it would be larger than most bridge projects across the mid-Columbia.

"But if we truly felt that it was the answer, we would not shy away from it," Pevan says. "We just don't believe it's the answer and we think we can use the water more efficiently. And that does mean generate electricity and at the same time safely guide fish around the project."

If just salmon safety were at stake, Bickford agrees a sluiceway or direct spill is the answer. But to best meet the combined needs of energy consumption, profit margins and salmon, he says the current multi-option plan is the best.

"Spill is very inefficient at Rocky Reach," he says. "To even meet 95 percent through the spillway, you would have to spill almost the whole river - 80 percent. And then what actually happens is that by doing that, you have gas super-saturation problems."

He says earlier problems with intake screens de-scaling salmon have been reduced since construction of a large surface collector for the salmon bypass tube in the Cul de Sac changed water flow dynamics.

Despite concerns from tribes and the potential threat of a lawsuit if they move to implement the Habitat Conservation Plan, Chelan PUD seems satisfied the current plan is worth implementing.

Chelan PUD hopes to start construction of the bypass system next year after the Habitat Conservation Plan is adopted and the EIS is complete. Between construction, operation and maintenance, plus water lost for energy purposes down the bypass pipe, the utility estimates the cost will be about $160 million.

"The thing that we get worried about is the re-licensing," says Heinith. "We get worried that they're going to go ahead and spend all this money and they're going to end up with a system that doesn't work so well.

"There's a whole host of problems with these techno-fixes. We're just saying let's get back to the basics and dedicate the waters necessary to move these fish on through ... quickly so they are in good shape and protected as they do it."