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BPA Wants Expanded Testing
of Turbine Rule for Fish

by Barry Espenson
Columbia Basin Bulletin - December 19, 2003

The Bonneville Power Administration would like to see expanded testing next year of the long-held theory that operating hydro turbines near peak efficiency provides the highest survival for juvenile salmon.

A proposal to evaluate the effect on survival of deviating from the "one percent efficiency" rule would expand from a limited test at a few units to across all 14 turbines at McNary Dam.

Participants at Thursday's System Configuration Team meeting were told that allowing suspension of the rule could put an additional $14 million annually on average in BPA's coffers.

The operation of turbines within one percent of their peak efficiency is called for in NOAA Fisheries' 2000 Federal Columbia River Power System biological opinion. That document is intended to assure that hydro operations don't jeopardize the survival of salmon and steelhead listed under the Endangered Species Act.

Relaxing the rule would have the effect of allowing the dam operators, the Corps of Engineers, to send more water through the turbines. Because of the rule of operating turbines within 1 percent of their peak efficiency the flow is around 12,400 cubic feet per second through each turbine. The turbines' capacity is 16.4 kcfs.

BPA officials believe the switch can be made without greatly affecting the fish. But fish managers feel that a full power house test is too risky given the uncertainties both of survival through the turbines and entry to the dam's gatewells.

The issue, long-debated at the technical level, has been broached at the policy level during recent meetings of the top regional representatives of federal hydropower and fish management.

A relaxation of the rule would allow the dam operators to channel more water through the turbines in spring and summer, particularly at times when high river flows force "involuntary" spill. BPA's Kim Fodrea said that analysis done by the agency indicates that, based on a 50-year record, the increased flow through the turbines would generate from zero to $26 million annually over what is generated under the one percent rule. The zero would be in extreme low water years.

Resolving the issue of whether the one-percent rule is necessary is one potential option for increasing flow through McNary, which has the lowest hydraulic capacity of the dams on the lower Columbia. New state-the-art-turbines expected to be both more fish friendly and allow greater generation have been eyed by BPA and the Corps of Engineers. But the costs estimates are high -- $160 million or more for the project.

NOAA Fisheries' Bill Hevlin said Thursday that "we don't support 16K operations at all the units" in 2004 as BPA is proposing. Hevlin is chair of SCT, a technical forum created by the BiOp to prioritize research and capital improvement projects at the mainstem hydro projects with the goal of improving fish passage survival.

"It's too great of a risk to our endangered fish. We just can't jump there. We'll take some risks when there's enough information there that we know we're not way out on a limb," Hevlin said. He said a year or more of research "operating a couple turbines" at flows exceeding the one percent efficiency is needed before a shift to a full powerhouse could be contemplated.

NOAA's Steve Rainey said that past research shows that there is a "strong enough correlation" between high efficiency flows and higher fish passage survival turbines to justify a cautious approach. Fodrea said a reanalysis of the data from those past studies found fault with that perceived correlation.

"We decided this rule wasn't well founded in the first place," Fodrea said. BPA does not want to push off a full powerhouse test, he said.

"We're saying that is too long. We're willing to accept the risk," Fodea told the SCT. BPA's favored option would be a test at all 14 units at flows at the one percent efficiency level and above. The flows through the turbine would be increased as the demand for power warranted. The cost of that proposed study is estimated a $3.3 million, which would likely have to be paid for by BPA directly or through the Columbia River Fish Mitigation Program's already cramped budget.

"What Witt said yesterday is that we don't have the money to do that," the Corps' John Kranda said. Witt Anderson, chief of the Corps' Northwest Division Fish Management Office, participates in meetings of the federal executives held this week to discuss this and other topics. The Corps expects to have about $70 million to spend on research and capital projects in 2004 and already has a list of as much as $77 million worth of projects that it would like to carry out.

Fodrea said Bonneville has been pursuing more full scale testing of the turbine flows for more than a year as it looks for "more effective ways of operating." Frustrated with salmon managers rebuffs in NOAA Fisheries technical forums, BPA decided to elevate the issue to the policy makers' level.

"There's no data to support the rule yet we're forced to spend millions of dollars" on pilot scale tests, Fodrea said. There is $2.1 million earmarked in the budget for a survival/efficiency study through two turbines.

"My feeling is that we're no longer in a technical argument," Fodrea said.

During Thursday's discussion, Rainey decried the fact that the full powerhouse proposal had essentially circumvented the NOAA Regional Forum process in which technical groups first review study proposals. He said his office had just received the information on the new proposals two days earlier.

He said NOAA concerns go beyond the fear that the dam's most hazardous passage route might be made even more dangerous with increased flows.

"That's about a third more water flowing through the gatewell and a third more debris through the gatewell," Rainey said. "We can barely stay ahead of the debris at 12.4 kcfs."

That extra debris load would plug screens designed to steer young fish toward the mechanical passage route.

The reduction in spill is also "a big concern" because more fish would likely go through the turbines.

"Are they going to survive at that 98 percent level" that can be expected from spill passage, he said.

Barry Espenson
BPA Wants Expanded Testing of Turbine Rule for Fish
Columbia Basin Bulletin, December 19, 2003

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