Corps Discusses Plan for 1,200 Foot Chamber Construction at Lock 25View Source
The Corps of Engineers project team in charge of the Lock & Dam 25 construction is moving ahead, while reconfiguring its plans now that it has full funding.
Mike Feldman, P.E., the Lock & Dam 25 project manager, led a presentation to potential contractors on a Corps Industry Day March 2. Lock & Dam 25, located at Mississippi River Mile 241.4 near Winfield, Mo., north of St. Louis, is the linchpin of seven locks and dams that are included in the Navigation and Ecosystem Sustainability Program (NESP). Its completion has long been a top goal of the inland waterways industry. It was authorized in the 2007 Water Resources Development Act, but only received start funding—and funding to completion, at $732 million—in the recently passed Infrastructure Investment and Jobs Act.
Feldman said the Corps already had a design plan for taking the new 1,200-foot lock chamber to 95 percent completion, but that plan assumed funding constraints. Now, with full funding, the project team is adjusting the plan to build in more efficiencies. One of the goals of Lock & Dam 25 is to test standardized parts and processes for use in multiple locks and dams that can save time and money, Feldman said.
One of the first things that has to be addressed at the site, Feldman said, is a scour hole in the riverbed that will have to anchor the approach walls. It was stabilized between five and eight years ago with stone material, but that will have to be partly removed and replaced with dredged material more suitable for piledriving. A containment berm will be built to hold the dredged material.
Feldman then showed aerial photos of the shoreside site, where a laydown area will be established. Road improvements may be necessary. “We anticipate a lot of river delivery of supplies and materials,” Feldman said.
Another Industry Day will be held in either June or July to solicit further industry and contractor feedback. “We’re still working through details,” Feldman said.