More than two years after high water strained the U.S. Army Corps of Engineers dam system along the Missouri River, work continues to make repairs to the structures.
This year, repairs are being made on Fort Peck Dam’s gates, the spillway slab, plunge pool, recreation area roads and drains, the spillway access road and drains and rehabilitation of eight emergency gate controls.
The four projects cost about $43.5 million. That’s only a fraction of the $234 million the corps is spending on more than 100 repair projects along the Missouri River from Fort Peck downstream.
The $43.5 million also is substantially less than the $225 million that was originally requested for repairs to Fort Peck Dam, which would have included strengthening the spillway to handle flows up to 265,000 cubic feet per second. During the 2011 high water event, the dam’s peak outflow through the spillway was 66,000 cfs.
Instead, the corps hired ASI Constructors Inc. of West Pueblo, Colo., to repair the plunge pool at the base of the spillway at a cost of $34.4 million. That project is not expected to be completed until 2015.
The next most expensive repair is the $6.6 million being spent on the spillway gates. That work is expected to be finished next year. The contract was awarded to J.F. Brennan Co. Inc., a marine construction company from La Crosse, Wis.
“There will still be a lot of work going on with those two jobs,” said John Daggett, Fort Peck project manager.
The two easiest and least-expensive projects at Fort Peck were completed last year. They included a contract to install 17 relief well outfall pipes that alleviate pressure on the downstream toe of the dam, which was awarded to Prudent Technologies Inc. for $122,748; under-seepage control was a $6,900 project completed by Lakeside Excavation.
Fort Peck Dam was completed in 1940 after seven years of construction. It is the largest hydraulically filled dam in the United States. The structure received its most intensive test on June 15, 2011, when the reservoir reached a record elevation of 2,252.3 feet above sea level.
Flooding during the unusually wet spring of 2011 caused more than $2 billion in damage and five fatalities along the Missouri River and prompted the Federal Emergency Management Administration to issue disaster declarations in each Missouri River state.
(Brett French is a reporter with the Billings [Mont.] Gazette.)