McNary Provides Multiple Functionsby Tammy Malgesini
East Oregonian, May 4, 2007
Dam operations impact power, fish survival, navigation, recreation
McNARY - At the McNary Lock and Dam, human ingenuity harnesses the power of the Columbia River to produce hydropower, study fish behavior, transport goods and provide recreation.
The U.S. Army Corps of Engineers operate and maintain eight dams within its Walla Walla District, including McNary Dam approximately one mile east of Umatilla off Highway 730.
The four major functions of the dam include hydropower, fish support programs, navigation and recreation.
Hydropower is harnessed through 14 turbines located in the dam's powerhouse, with the capacity to generate 1,000 megawatts. One megawatt would equal the power of approximately 800 microwave ovens.
Randy Ryan, operations manager at McNary Dam said $45 million worth of power has been generated at the dam since Jan. 1. The yearly cost of operating the dam is $15 million.
"We've already gone over the break-even point for the year," Ryan said Thursday. "Everything on top of that is gravy."
About 48 percent of the power used in the Pacific Northwest is obtained through hydropower. Other resources include coal, combustion turbines, cogeneration, imports, nuclear and non-utility generation.
Joe Saxon, a public affairs team leader with the Corps of Engineers, said hydropower is clean, renewable, reliable and efficient.
"No system is perfect, but as far as compromises - this is the way to go," he said.
Ryan said the dam has a "black start capability."
If an energy failure occurs, the hydropower is designed to self-start in the smaller units and then move on to the bigger units.
"It's a domino process," he said.
This technology helps restore electricity in case of blackout situations.
A $52 million fish program is operated by the Walla Walla District to assist juvenile salmon and steelhead as they migrate to the Pacific Ocean. The juvenile fish are transported over, around and through the damson their downstream journey.
The fish are aided by a juvenile bypass system, which includes fish screens to keep them out of the turbines in the powerhouse, routing them into collection facilities or guiding them back into the river below the dam.
Others are collected and transported to an estuary below Bonneville Dam in barges or trucks.
Some of the juvenile fish are implanted with passive integrated transponders for fish research and monitoring.
Although the powerhouse's turbines rotate at 85.7 revolutions per minute, fish are minimally impacted. Ryan likens it to a fish going through a revolving door, not a blender.
"Our tests indicated 97 percent of the fish that go through a turbine are unharmed," Ryan said.
However, with additional studies and testing, fish biologists are targeting for a 100 percent non-injury rate.
In March, temporary spillway weirs were installed in two of the spillway bays at McNary Dam to determine if their use would increase fish survival rate.
With the use of the tracking devices implanted in fish, biologists can study how fish respond to their environment. Information gleaned can assist biologists in further developing technology to reduce injury to fish.
With water plummeting at approximately 1,000 cubic feet per second, fish biologists are attempting to lure fish to the temporary spillway weirs to reduce the turbulence of the area where fish are passing through.
"It's a behavior and survival study for us," said Ann Setter, a fisheries biologist.
Setter is hopeful to glean information to increase the likelihood fish will be attracted to the surface passage, rather than over the spillway.
Using the technology of the tracking devices, physical counting of fish and floating transponders near the spillways; virtually every fish is accounted for.
"There's not going to be a fish anywhere that doesn't get detected out here," said Brad Eby, another fisheries biologist.
Although the studies may reveal changes need to be made in the turbines to decrease the fish injury rate, Cary Rahn, project manager for the Columbia River Fish Mitigation, recognizes the dam is a multi-purpose facility. Hydropower operation and navigation needs also are considered in the equation when making changes.
Use of the navigation locks enables more efficient transportation of goods than semitrailers. One barge's load capacity would equal between 120-134 semitrailers.
Not only can more tonnage be moved by barges, but at a cheaper cost. Gallons of fuel needed to ship cargo from Lewiston, Idaho, to Portland by barge are approximately 2,000. The same amount of cargo shipped by rail would require 5,000 gallons and by truck 17,000.
Recreational activities offered on Corps land include fishing, boating, hiking and observing wildlife.
David McDermett, a park ranger, said wildlife in the area include whitetail deer, beavers, badgers, coyote and birds.
"It's a destination point with picnic areas, fishing, recreational boating and water-skiing," he said.
Three park rangers are available to answer questions at interpretive displays and provide water safety programs.
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