Update on St. Mary Siphon Rehabilitation

On Thursday, August 1, the Bureau of Reclamation (BOR) and the Milk River Joint Board of Control updated stakeholders on the rehabilitation efforts following the St. Mary siphon failure on June 17. The failure halted water transfers from the St. Mary system, resulting in widespread water shortages throughout the Milk River basin.

Steven Darlinton with the Bureau of Reclamation reported that NW Construction is conducting the rehabilitation of the failed siphon site through a modification to the existing Diversion Dam contract, allowing for a quick start. The contract includes the removal of the damaged St. Mary Siphon, site cleanup, some site preparation for new pipe installation, and restoration of the affected river. M&D Construction is responsible for removing and transporting the steel from the site to Steel Etc. in Great Falls for recycling.

Sletten Construction has been contracted by the Milk River Joint Board of Control to install a new bridge to support the siphons and provide a maintenance lane for future work across the river. Sletten Construction is currently mobilizing equipment and preparing a pad for their large crane. Additionally, the Joint Board is negotiating a contract with NW Construction for the installation of new siphons at both St. Mary and Halls Coulee. The project timeline includes the installation of a temporary bridge starting August 5, 2024, demolition of the old bridge around August 19, 2024, and site rehabilitation concluding by September 5, 2024. The straight sections of the 90-inch steel siphon replacement pipe have been ordered and are expected to arrive on-site in early October 2024.

The estimated cost for replacing the St. Mary and Halls Coulee siphons is $70 million. Repayment letters have been sent to project beneficiaries, enabling municipalities, irrigators, and pump contractors to explore funding options and loans. Currently, secured funding includes $9.2 million from the Joint Board and $7.5 million from BOR, with the project projected to run out of money by November 1, 2024. Additional identified funding sources include $26 million from the State of Montana through HB 6, which is under negotiation as an interest-only loan, $37.2 million from the BOR Aging Infrastructure Account, and $750,000 from the Emergency Watershed Protection Program, coordinated by Natural Resource and Conservation Services and the State DNRC.

Securing these additional funding sources is crucial to avoid construction delays. The BOR emphasized, as mentioned during the July 9, 2024, Tin Cup meeting, that the siphons are not expected to transfer water from Sherburne Reservoir to Fresno Reservoir until at least August 2025. Jennifer Patrick of the Milk River Joint Board stated, “We will continue to host bi-weekly stakeholder calls every other Thursday until winter shutdown to provide critical updates on the project. From a construction standpoint, it’s important to note that we are all pushing this project forward and will seize every opportunity to expedite these fixes and restore water flow to the Milk River. We are also working diligently to keep our Milk River Project Facebook page and http://www.milkriverproject.com website updated to ensure the public stays informed.”