History of Flower Creek Dam

There are several big projects that the city began undertaking in 2012.  These included preparation for the construction of the Flower Creek Dam in 2014; major repairs to leaking water distribution lines; installation of pressure reduction valves and curb-side water meters for properties with broken meters; street repair; new sidewalks on the north end of Louisiana; and dedication of Riverfront Park.

Our biggest project is Flower Creek Dam.  The City has made the decision to replace the dam because of the loss of strength of the concrete in the dam through many years of seepage.  There is also the serious concern of public safety with the possibility of failure of the dam.

Council considered several options including more repairs and other water sources besides Flower Creek.  The council unanimously chose replacement as the most cost effective, long- term choice to ensure a viable water source for Libby’s future.  The City considered replacement to be the only realistic option.

Below is a history of issues with the dam.

1946—Construction of the Dam

1966—Vrious areas repaired with higher quality concrete, construction joints and cracks grouted, epoxy applied to upstream joints and cracks.

1978—The dam is leaking again

1995—Installation of a synthetic liner on the upstream side

2009—State inspection for renewal of 5-year operating license; seepage becoming more severe

2010—17 core samples of the downstream face reveal substandard concrete in the original construction; fracturing of concrete allowing seepage; overall concrete strength below acceptable levels; concrete strength will continue to fail

2011—State letter to City: “the Department does not believe that the Flower Creek Dam is in imminent danger of failing, but we do feel that the City needs to move forward with all due diligence to either have the Flower Creek Dam replaced or repaired.”  The City decides to replace the dam.

2012—The City constructs a new access road to the dam and pays for drilling of the bedrock to choose a suitable location for the new dam.

The estimated cost of building our new dam is $8.5 million. The exact cost will not be known until the project is put out to bid. Our engineering firm has secured $850,000 in grants and hopes to secure another $450,000 for a total of $1.3 million in grants.

Rural Development, a federal agency that assists rural communities with expensive public works projects, will provide the remainder of our financing.  We hope to receive a grant of 45% for the remaining amount and only have to borrow 55% 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.

In preparation for construction in 2014, twenty-five feet of the fifty-eight foot high existing dam will be removed this summer or autumn..  This project, when completed, will protect our community from a dam failure.  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.

The community is welcome to review engineering documents at city hall or call with questions.