Lock and Dam 2 at Hastings above Prescott on the Mississippi will soon feature four new Tainter valves, replacing ones first installed in the 1940s. The new steel valves began the design process in 2022, with a $3 million contract with OCCI Inc. in 2023 for fabrication in Missouri. Delivery was by barge and should take six weeks total to install, after the process began Sept. 20.

Those involved in leading the project include Senior Project Manager Billy Thomson with the St. Paul District Army Corps of Engineers, Contracting Office Representative Ben Rhoda, Project Technical Lead Faith Sandberg, and Master Tender (boat operator) Brandon Johnson.
The new Tainter valves at Lock and Dam 2 are part of a proactive replacement project after inspection found the current valves to have pitting and are being installed by a crew out of Fountain City. They are painted for corrosion protection and utilize composite bushings instead of brass to avoid releasing grease into the water. The new valves are engineered for 50+ years but will require sandblasting, painting to fight corrosion, and pin/brushing replacement in about 20 years for maintenance.
Tainter valves are named after American engineer Jeremiah Burnham Tainter, build on a design first originated by Thomas Parker, allowing for water release in Wisconsin's logging era.
Now used worldwide, Tainter valves are composed of a curved skin plate attached to an iron framework that connects to a pivot point, allowing the gate to raise and lower as needed to regulate water flow.
The ones on the navigation lock at Lock and Dam 2 at Hastings are reverse orientation, meaning they catch water flowing into them, with a rubber seal to prevent leakage. The new valves are arranged in pairs, with two at the front of the navigation lock and two at the back of the lock.
By raising or lowering the respective valves the water level is lowered and raised in the lock. No pumps are involved, with gravity and water flow used instead to draw levels up or down at the lock. A total of 40 portholes or 20 on each side are used to manage water flow. Physical inspections were conducted by divers in 2022 to assess the vulnerability of concrete walls and steel members. The site was de-watered in 2024 for maintenance tasks.
Installing the new Tainter valves meanwhile started last week with the front of the lock. In order to work the area of the Tainter valve alongside the lockhead is closed off with bulkhead, a large metal piece inserted in a slot behind the valve area to control water flow. The Tainter valve area is then drained allowing crews to remove the old welded valves and replace them with new bolted ones. The valve area itself is 37 feet deep. Divers are not used in the installation process, the Tainter valve area being drained to facilitate work. The two upstream valves remain closed while the two downstream ones are raised to release water and lower the water in the chamber.
Once complete, the installation of the new Tainter valves will facilitate river traffic for years to come, with cement and fertilizer carried upstream in the spring and crops carried downstream in the fall.