Reduced river flows lower flood concerns

        By AARON BOHACHEK

Staff writer

BONNERS FERRY — The Kootenai River should reach its maximum yearly inflow around the middle of June, said Boundary County Incident Commander Bob Graham.

With 119 percent of average water forecast for April to August and snow to water equivalents at 110 percent, the Libby Dam is sitting close to minimum elevation for the year.

The refilling period has not officially begun but inflow peaked out at 24,000 cubic feet/second earlier this week with heavy spring rains and the elevation climbed to around 2,387 feet.

With outflows at 20,000 cfs Wednesday, the dam was using all five power turbines at low level.

The level around Bonners Ferry was over 58 feet, above action level but below the 64 foot flood stage. With current reduction to 16,000 cfs using four turbines, the level should drop until peak releases for sturgeon in mid May.

According to Corps Civil Engineer Kristian Mickelson, the probability of flooding has been reduced to 10 percent, with the chance of a massive snow melting event downstream of Libby Dam much lower.

Hydraulic engineer Kevin Shaffer said the May forecast sets the summer minimum flows for bull trout, as well as the sturgeon flow augmentation volume.

The bull trout minimum flow from May 15 to Aug. 31 will be 9,000 cfs, and the volume to be released this spring and summer for sturgeon flow augmentation will be 1,200K acre feet.

The exact day will depend on a real-time decision made

See RIVER, A-3

RIVER

From A-1

by all interested parties, including the Army Corps, Kootenai tribe and federal agencies.

Peak releases will see a week at 25,000 cfs, then a reduction to 18,000 cfs for a week, followed by a second peak release of around 26,000 cfs depending on water levels in Lake Koocanusa, said Mickelson.

The bull trout minimum flow for Sept. 1-15 is 6,000 cfs.

Graham expects to see modified protocol from the Army Corps soon. A flood assessment group will be in Bonners Ferry on May 14 and a public information meeting will be held May 29.

Only dikes at the city of Bonners Ferry currently qualify for flooding help from the Army Corps, said Graham.

The Herald’s e-edition is still free, so to read the complete story, go to: http://www.bonnersferryherald.com/