GARRISON, N.D. (NewsDakota.com) – Senator John Hoeven, alongside officials from the U.S. Army Corps of Engineers, reviewed progress today on the $1.8 billion spillway safety project at Garrison Dam. This critical initiative aims to ensure the long-term integrity of the dam, which is the largest mainstream dam on the Missouri River. It also oversees Lake Sakakawea, the largest reservoir managed by the Army Corps by volume.

The project will address multiple long-term safety concerns at Garrison Dam that could potentially lead to uncontrolled water releases. These risks became evident during the record-breaking water flows of the 2011 flood. In the aftermath, a comprehensive study recommended a complete overhaul of the spillway’s drainage system, a reinforced concrete overlay in the spillway chute, and other key safety modifications.

The project is currently in the Preconstruction Engineering and Design (PED) phase, which began in 2023, utilizing funding that Hoeven secured as a member of the Senate Energy and Water Development Appropriations Committee. The PED phase, which will take six years of field investigations, will inform the final design, with construction slated to begin in 2029.

To date, Senator Hoeven has secured nearly $13 million for the design phase, with an additional $32 million in PED funding included in the Senate’s Fiscal Year (FY) 2025 appropriations legislation.

“The Garrison Dam, along with the Lake Sakakawea and Lake Audubon reservoirs, are critical infrastructure for our state, providing reliable water supply for communities and agriculture, while also supporting recreation and tourism,” said Hoeven. “A key function of the dam is to control Missouri River water levels, which helps protect the region from the risk of flooding. The historic water flows during the 2011 flood revealed that the spillway needs modifications to ensure the dam’s long-term integrity. We’ve been working to fund the pre-construction and design phase to address these safety concerns as quickly as possible.”

The project represents a significant investment in ensuring the stability of Garrison Dam and the safety of the surrounding regions. As the PED phase continues, officials are optimistic about future construction to safeguard the dam against potential threats for decades to come.