Lawmakers express concerns over lengthy Arkabutla Dam modification project

• Nearly a decade of work is planned by the U.S. Army Corps of Engineers on the Northwest Mississippi dam.

Elected officials want an accelerated timeline for the completion of the Arkabutla Dam modification project, but the U.S. Army Corps of Engineers, Vicksburg District, said the project is moving as quickly as possible.

During a hearing earlier this week before the Mississippi House Ways and Means Committee, Colonel Jeremiah Gipson, commander of the district, told lawmakers repairing the Northwest Mississippi dam is a complex undertaking, which includes calling in the nation’s top civil engineers and waiting on Congress to act.

“We are putting the best engineers on this portfolio,” he said. “The Corps of Engineers doesn’t do anything without congressional authority and appropriation.”

House Committee Chaiman Trey Lamar (R) said the Corps has some of the “smartest people in the world” employed, so it seems that the agency “could do it a little bit quicker” concerning the $830 million project.  

According to the Corps, the current plan estimates nearly a decade of work on the dam. For a project of this scale, this longer timeline reflects the time needed to design the fix, have it reviewed and approved, obtain construction funding, and carry out the construction in phases to minimize downstream risk during construction, the Corps outlined.

The Corp stressed that both the price and timeline are preliminary estimates, but the design will be more efficient.

“I know it’s not the right timeline, but what we don’t want to do is in 20 years from now say we got it wrong,” said the commander.

The problem started in May 2023, when an opening larger than a concrete highway jersey barrier was discovered under the dam. The Corps immediately lowered the water levels to alleviate pressure on the nearly 80-year-old structure.

This action, explained Will Bradley, chief of engineering and construction for the Vicksburg District, reduced the chances of a breach. The drawdown is an ongoing safety measure approved by their headquarters as a “major deviation” from normal operations, the Corps said.

Several members of the House committee questioned if a breach was possible and if so, how long did area residents have to evacuate. The Corps estimates that the nearly 2,500 residents would have around 36 hours to evacuate.

One lawmaker asked why it only took three years to build the dam but will take three times as long to repair it. Colonel Gipson explained that while the construction took three years, the amount of time for design work and funding that preceded the work was not factored in. He continued by saying the repair work to adhere to modern safety standards is very different than building a dam from scratch.

During the two-hour hearing, the Corps said the Arkabutla Dam has received a 1 on its Dam Safety Action Clarification ranking, the lowest ranking on the scale.

Arkabutla Dam Safety Modification Project Full Project Estimated Timeline

Below is the information the Corps has listed on their website regarding the full project estimated timeline:

The Arkabutla Dam Safety Modification Project is a multi-year effort. Here’s an overview of the key milestones and what to expect in terms of timeline:

• 2023 (Emergency & Study Launch): In spring 2023, a sinkhole and seepage issue were discovered at the dam, prompting an emergency response. USACE immediately began interim repairs (like grouting and planning for relief wells) and kicked off the Dam Safety Modification Study to analyze long-term solutions. This study phase involved experts investigating the problem and evaluating repair options throughout late 2023 and 2024.

• 2024 (Interim Repairs Underway): Early in 2024, USACE awarded a contract and installed six relief wells and additional monitoring equipment as a short-term fix to stabilize the dam’s foundation. 

• By fall 2024, the emergency drilling and foundation grouting work was largely completed significantly reducing immediate risk. Some grouting does remain as part of Phase II of the interim repairs. Meanwhile, the dam safety study continued, and a tentative long-term repair was identified (ultimately, the plan to replace the outlet works – the dam’s water release system). 

• Environmental assessments and design prep were initiated in late 2024.

• 2025 (Study Completion & Design Start): Transition from planning phase into design of the final repair, which could take 4 to 5 years to complete. 

• Starting in summer 2025, you may see engineers and survey crews on site at Arkabutla collecting data to inform the design. The design phase will likely take a few years – this is when we create the detailed blueprints for the fix (replacement of the outlet works and any related dam modifications) and obtain the necessary permits and funding approvals.

• 2029-2030 (Construction Begins): If all goes according to plan, we aim to start major construction by around 2030. This could be a bit earlier or later depending on funding and design progress, but late this decade to 2030 is a reasonable target for breaking ground on the permanent repairs. Construction will involve building a new outlet works for the dam and possibly other supporting work like improving internal drains or buttressing parts of the embankment (as determined by the final design). We will keep the public updated as we get closer to this phase.

• 2030–2037 (Construction Ongoing): Building the new outlet works and making all necessary dam upgrades will take approximately 7 to 10 years of work on site. This lengthy construction period is due to the complexity of the project – we’re essentially performing major surgery on the dam, which must be done carefully and often in stages. During this time, the lake will likely remain lower than normal. We will also maintain any necessary closures for public safety throughout construction. It’s possible some recreation areas could reopen before 2037 if portions of the project finish early, but a full return to normal will coincide with project completion.

• By 2037 (Project Completion & Lake Refill): The current schedule estimates construction completed by around 2037, assuming no significant delays. At that point, all new dam components should be in place and thoroughly tested. We will then slowly refill Arkabutla Lake in stages to test the new embankment and outlet works. Once the pool is raised to normal levels the lake will resume normal operation. All recreation areas would be reopened, and the dam will officially be back to normal service with improved safety and reliability. 

Please note: These timeline points are estimates. Large infrastructure projects can be affected by funding cycles, weather, and other unforeseen factors. USACE is doing everything possible to expedite the work without compromising quality or safety. We will keep the community informed of any major changes to the schedule.