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Dam-crossing Helper for Fish Arrives at Lower Granite Dam by Associated Press Idaho Statesman - June 20, 2001

Weir designed to ease steelhead, salmon over spillway

LEWISTON -- An $11 million device to ease young salmon and steelhead through Lower Granite Dam toward the ocean will be installed this week, although fish advocates call it a waste of time and money.

The 1,000-ton weir will be installed on a spillway gate as the next step to improve fish passage conditions at the dam, U.S. Army Corps of Engineers spokesman Dutch Meier said.

The corps has installed screens, a surface bypass collector and "behavioral guidance structure" to direct young fish away from turbines. For years, it has collected them and barged them around most of the reservoirs.

"That's two of the three ways a fish gets past a dam," Meier said.

Now, the federal agency is trying to improve spillway passage. The removable weir is designed to ease fish over a spillway instead of shooting them through its opened gates, where they face water pressure and dissolved gases that act like the "bends" on divers.

Meier said the weir will create a false waterfall that attracts and passes fish near the top of the water column.

It will be mechanically tested throughout the summer, and biologically tested next year. Biologists will track radio-tagged salmon and steelhead smolts as they pass the dam to determine if they use the new route.

Last year, the federal government decided not to recommend breaching the four lower Snake River dams for now, opting to determine if other measures save the runs.

The weir is the latest in technological additions tested at Lower Granite.

"That's lovely, but it's a waste of taxpayer money," Idaho Rivers United Executive Director Bill Sedivy said of the weir. "They know as well as we know and anybody with any scientific credibility knows, the only way to bring these fish back is to remove the four lower Snake River dams. This may help, but it's not going to solve the problem."

The surface collector and behavioral guidance system have been retired for the time being at Lower Granite.

Each provided an incremental improvement to salmon passage, but biologists where unable to say they worked well enough to install the prototypes at each of the dams on the Snake and Columbia rivers.