Olmsted Locks and Dam: Improving the busiest stretch in America’s inland waterways

One of the largest civil engineering projects undertaken by the United States Army Corps of Engineers (USACE), the Olmsted Dam project, operational in 2018, is a $3 billion, a 30-year project that required numerous engineering innovations and a team that dedicated millions of hours. 

Replacing previous locks and dams called No. 52 and 53, originally built in 1929, as well as the 1,200-foot-long lock chambers added in 1969 at 52 and 1979 at 53, the Olmsted project solves one of the largest bottlenecks for America’s shipping industry at a critical part of the Ohio River.

The dam and locks’ aging infrastructure was making it nearly impossible to meet current traffic demands without significant delays, and resulted in higher export costs, transportation taxes, and an increase in the number of trucks clogging America’s highways.

Located on the busiest stretch of U.S. commercial inland waterways, near the confluence of the Mississippi, Ohio, Tennessee, and Cumberland Rivers, the Olmsted project provides a year-round channel for navigation starting in Pittsburgh, Pennsylvania and ending at Cairo, Illinois. More tonnage transits through this point on the Ohio River than any other place in America's inland navigation system—the approximate equivalent of 25,000 semi-trucks passing through annually. In recent years, approximately 90 million tons of commodities have passed through the two locks and dams that Olmsted replaces; items like coal, grain, rock, and sand.

Jacobs, as lead partner of the Jacobs/Gerwick Joint Venture design team, supported the USACE by designing key segments of the dam, including the Tainter Gate Section; Navigable Pass, and Fixed Weir.

As USACE’s partner for joint venture design team of the Olmsted Dam, Jacobs poured more than 130,000 hours of work into the dam upgrades. Our design implemented constructing the dam’s tainter gated and navigable pass sections using innovative in-the-wet construction techniques versus the more traditional coffer dammed in-the-dry construction method.

Traditional techniques require using cofferdams as temporary dams to create a large dry space around the work site so that dam cells could be poured in place. The lock portions of the project were built “in-the-dry”, behind a traditional cofferdam. The “in-the-wet” method, which had less impact on barge traffic and the constantly changing water levels of the Ohio River, involved casting dam sections ashore and moving them into place using barges. The modular nature of the construction means that in a given year the amount of work in the river can be tailored to the available budget and the working conditions in the river. In addition, by eliminating cofferdams, the river bottom is not disturbed – a habitat critical to the survival of nearby mussel beds located just downriver from the construction site. Commercial and economic benefits are also derived from improved navigation for river traffic while the project is under construction.

In addition to the non-traditional way of building the dam, our joint venture team conducted a series of engineering planning studies.  We determined the most cost-effective size and a number of gate bays and evaluated the most cost-effective gate operating system.

Because Olmsted sits directly atop the New Madrid Fault and is the single busiest lock on the inland river, this method posed a major challenge to the project and required the use of special isolation joints between sections of the project to allow the lock and dam structure to flex in the event of an earthquake—another innovative solution.

Since the award of the construction contract in January 2004, Jacobs has provided construction phase support to the USACE and the Contractor, including engineering in support of the Contractor’s Means and Methods of the work.

Now completed, the project consists of two locks, each measuring 110 feet wide by 1,200 feet long; a dam composed of five tainter gates; and 1,400 feet of steel wickets in the navigable pass section that can be manually raised by a wicket lifter barge to help impound the pool. Eighteen dam tainter gate shells were set in the river bottom to support the tainter gates. Twelve shells were set for the navigable pass section.

Water-borne transportation is the most economical for transporting bulk commodities like coal, grain aggregates, petroleum, and chemicals.

The strategic reach of the Ohio River provides a connection between the Mississippi, Tennessee, and Cumberland rivers. More tonnage passes this point than any other place in America’s inland navigation system. In 2012, 91.4 million tons traversed this portion of the Ohio River. Commodities also move through this stretch to the Port of New Orleans for overseas markets.

USASCE estimates the annual net benefits of the project at $640 million annually. The Ohio River navigation system is saving American consumers millions of dollars each year and also conserving energy resources while reducing operational and maintenance costs.