The much-awaited construction of the new Flower Creek Dam in Libby is about to begin, according to Mayor Doug Roll.
The reservoir behind the dam, located southwest of the city, has been lowered and contractors have begun moving equipment onto the site so that construction of a new dam can start within the month. The project is estimated to cost more than $8 million and is part of a multi-year water system improvement project in Libby.
At the same time, Libby recently raised water rates in order to pay for the improvements. Roll said the city had hoped it didn’t have to raise rates, but noted that the infrastructure improvements were critical.
“There is a big issue with aging infrastructure across the nation,” Roll said. “We’re not alone.”
The dam was built in 1946 and holds back the community’s drinking water. In 2010 it was deemed inadequate and engineers say it could be compromised if there were a major seismic event in the area. Morrison-Maierle completed a core sample test of the arch dam and found that the concrete strength was less than 1,000 pounds per square inch. Normal strength is between 3,000 and 4,000 pounds per square inch. A report, issued by Morrison-Maierle in September 2011, stated that under normal conditions the dam would be usable for another five years. If a seismic event did compromise the dam, Flower Creek and Libby could be flooded. In 2012, Lincoln County installed a new sensor and alert system at the dam. If there were a sudden drop in water behind the dam, 911 dispatchers would be notified and could view images of the site to decide if a siren should be sounded in the city.
The new dam will be built 85 feet downstream from the current one and will cost an estimated $8.4 million and will be covered by various government loans and grants.
Although city officials said they believed the project was critical to the city’s infrastructure, it has dealt with numerous delays over the last few years, particularly after the U.S. Fish and Wildlife Service rescinded a 2012 comment on the project and asked that a biological assessment of local grizzly bear, Canada lynx and bull trout populations be completed before the project moved forward.
The dam construction comes after the city wrapped up its water-main improvement project, which took more than a year and a half. Roll said the city was able to replace about 10 percent of the water mains in an effort to reduce the number of water leaks in the system. Despite those improvements, Libby’s water system still has issues and city employees have been dispatched to complete emergency repairs on the water mains on numerous occasions over the last few months. The most notable incident occurred in November on U.S. Highway 2 and closed the main route through town for nearly 15 hours.
In order to pay for some of the improvements, the city has raised water rates. Previously, city residents paid a base rate of $33 a month for 3,000 gallons of water. For every additional 1,000 gallons people would pay $2.96. Now people pay a base rate of $36 and an additional $2.96 for every 1,000 gallons of water they use.
Rolls said the rate increases would have been steeper had it not been for money the city received a few years ago in a settlement with International Paper because of a groundwater contamination at the old lumber mill.