Flower Creek Dam needs to be replaced
by Duane Williams, KLCB-KTNY Radio
January 4, 2011
LIBBY - Morrison-Marilee engineer, Ryan Jones, told the Libby City Council the City owned 65-year old Flower Creek Dam needs to be replaced within the next five years. The dam provides the sole source of city water.
The dam is being inspected for relicensed by the State. 17 core samples were taken, but only three were able to be tested, because the others disintegrated. The problems stem from concrete quality problems during initial construction 65 years ago.
It poses a safety problem. While the dam is, most likely, not in imminent danger of failure except from a seismic event, Jones told the Council it will not pass inspection in five years. It appears to be deteriorating at an accelerating rate, he said. Major work was done on the dam in 1966. The dam is leaking up to two gallons per minute through the face in some spots.
It raises serious questions about finding alternative sources of water for the city. Deep wells had been investigated some years ago, but aquifer pollution from the lumber mill makes that not viable. Flower Creek remains the most viable source for city water.
Replacing the Flower Creek dam with the same arch design currently in place will cost an estimated $4-1/2 million dollars. Replacement with a mass structure similar to the Libby Dam construction has an estimated price tag of $5-1/2 million. Those numbers are an obvious funding issue. A replacement project would take 16 months to the bid stage, and two, maybe three years to completion.
Jones said he believes the State will require an early warning system to be installed immediately.
Jones made it clear that Morrison-Marilee is not saying the dam will fail in the next five years, but that the safety factor will not be there in five years to relicense the dam again.
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Story by Duane Williams, KLCB-KTNY Radio, www.todaysbestcountryonline.com, e-mail: klcb@frontiernet.net.
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