Arkabutla Dam

Relief Well Installation for Emergency Repairs

In 2023, the U.S. Army Corps of Engineers (USACE) discovered the Arkabutla Dam, critical infrastructure for flood control, was in a potential failure mode. Near the outlet conduit, multiple sinkholes were forming, and underseepage could destabilize the surrounding area of the conduit through the dam, from the reservoir to the outlet.

The dam was originally constructed in 1943, standing 10,000 feet long and 92 feet high. At normal pool elevation, it holds back 10,264,300,000 gallons of water. Preventing failure was critically important to prevent major floods and resident evacuation.

In December 2023, the U.S. Corps of Engineers solicited contractors for emergency repairs and the installation of six new relief wells. Contract Dewatering Services (CDS) and its contracting partner were the only bidders, with CDS ready and qualified to perform the highly technical work.

Drilling operations were conducted in an inherently high-risk environment defined by complex geology, active hydrology, and limited access. Before work began, CDS developed a comprehensive Drilling and Invasive Program Plan, incorporating detailed risk assessments and constructability reviews, which was approved by the USACE prior to work.

The six relief wells initially served high-volume dewatering needs, pumping up to 4,500 gallons of water per minute to support construction activities. By the end, three 70-foot deep relief wells on both the north and south sides of the outlet structure were placed on permanent service, relieving the underseepage pressures in a controlled manner and limiting the movement of foundation soils to restore dam stability.