The U.S. Army Corps of Engineers said last week the threat of a dam failure at Arkabutla Lake is real and they have taken steps to monitor the dam and have a plan to fix it.
Col. Jeremiah Gipson, Commander of the U.S. Army Corps of Engineers, Vicksburg District, said Thursday, Sept. 23, that problems with the dam have been known for some time and the discovery of a “depression” in the dam in March 2023 prompted the Corps to assess the problem and draw the lake down.
“We will be totally transparent and we’re here today to talk about Arkabutla,” said Gipson. “I want to say first that protecting the community is our top priority.”
Gipson said the problem is erosion in the conduit connecting the intake tower to the stilling basin on the lower west side. He said six relief wells and pressure monitors have been installed to detect any motion in the dam and draw off water. He also said grout was injected to stop the current leak.
It was explained the conduit is made of jointed concrete culverts and the leak started in one of those joints.
Gipson said the dam was designed to have “water stops” placed around each one of the joints when the dam was constructed in the early 1940s, but that apparently didn’t happen. He added he did not know why.
All of this means a new outlet must be constructed and the timeline for that is 10- to 15-years.
Thursday’s meeting in Jackson was called by State Representative Trey Lamar, chairman of the House Ways and Means Committee, and saw senators and more than a dozen representatives at the table with the Corps.
“Arkabutla Lake is in my backyard and we were concerned with the news in the spring of 2023,” said Lamar. “We know this is the first major problem with the dam and we are here today to ask how you are going to fix it.”
Gipson explained an emergency has been declared and Arkabutla Dam is one of the top three concerns of the Corps. The corps owns and operates 790 dams across the nation.
He said the Corps began planning repairs in 2023 and they now call for building a massive coffer dam just north of the existing control tower, digging to the dam’s base and then constructing a modern water control tower.
It was explained the problem and fix are complex and an estimated 1.3-million-yards of new fill will be needed for the coffer dam and dam itself.
The design phase is expected to take up to five years with actual construction taking an additional five to seven years. Arkabutla Lake would take several years to refill and at least five more years to return to normal.
Lamar asked if there was any way to speed up that process.
Gipson said he met with Senators and Representatives in Washington recently to explain the problem and the need for funding.
Gipson said the Corps has an emergency action plan in place and even held a tabletop exercise in Batesville July 23, to get local Emergency Management personnel onboard with details about how to respond to a dam failure.
When pressed by Lamar about how much warning communities along the Coldwater would have to evacuate, he was told 24- to 36-hours.
While Arkabutla Dam’s main job is water control, it is also a local source of tourism and recreation.
All boat ramps were closed except for the Highway 51 Landing. Most day-use and campground facilities remain open to the public.
Arkabutla’s drainage area covers more than 1,000-square-miles and pool levels can rise quickly, especially during the winter rainy season.
At the 220-foot pool level Arkabutla covers 10,610-acres. The current pool elevation is 204-feet covering 1,370-acres. In the event of forecast rain, the pool will be lowered to 200-feet covering 136-acres.
Again, the Corps said safety is their top priority, and the physical integrity of the dam remains stable. They added the physical condition of the dam remains unchanged and a dam breach is not imminent.
The U.S. Army Corps of Engineers, Vicksburg District, can be reached by calling 601-632-5000 and pressing Zero or online at VicksburgDistrict@usace.army.mi.
