Flower Creek Dam Moves Ahead

The city of Libby is moving ahead with plans for construction of a new dam on Flower Creek in 2014 at an estimated cost of $8.5 million.

The engineering firm contracted to oversee the project, Morrison-Maierle, has secured $850,000 in grants and hopes to secure another $450,000 for a total of $1.3 million in grant funding.

Rural Development, a federal agency that assists rural communities with expensive public works projects, will provide the remainder of the financing.

The City hopes to receive a grant of 45 percent for the remaining amount and only have to borrow 55 percent from Rural Development as a low interest loan. It is estimated, therefore, that the city will be borrowing around $3.9 million for the dam. It is important for the public to understand that the city and its residents are not paying $8.5 million for the dam.

The city has made the decision to replace the dam, built in 1946( with major repairs in 1966 and 1995) because of the loss of strength of the concrete in the dam through many years of seepage.

A state inspection in 2009, required for the renewal of a five-year operating license, found that seepage was becoming more severe. Core samples taken in 2010 revealed substandard concrete in the original construction, fracturing of concrete allowing seepage, and overall concrete strength below acceptable levels.

City officials were informed that while the dam did not appear to be in imminent danger of failing, repair or replacement was strongly recommended. The council considered several options including more repairs and other water sources besides Flower Creek before unanimously choosing replacement as the only viable option (Special Council Meeting,-March 10, 2011).

In 2012, the city constructed a new access road to the dam and paid for drilling of bedrock to choose a suitable location for the new dam.  The City also learned from a new report from dam specialist Paul C. Rizzo Associates in Pennsylvania that “strengthening of the existing dam is not possible.”   The City’s earlier decision to rebuild the dam was thereby reinforced.

In preparation for construction in 2014, 25 feet of the 58 -foot high existing dam will be removed this summer or fall. The reduced structure will be demolished before the reservoir is filled. There will also be preparation this year of the bedrock foundation before the dam is constructed next year.

Other major projects planned by the city for 2013 include repairs to leaking water distribution lines, installation of pressure reduction valves and curbside water meters for properties with broken meters, street repairs, new sidewalks on the north end of Louisiana Avenue, and dedication of Riverfront Park. There will be more information on those projects in the weeks to come.

The community is welcome to review engineering documents and letters at City Hall.

Next Week:  Upgrading our water distribution system