U.S. Army Corps of Engineers Olmsted, Illinois, United States

Constructing the largest civil works project ever undertaken by the U.S. Army Corps of Engineers

Olmsted Dam constructing a mega-project civil works project

Constructing a mega project on the busiest stretch of inland waterway in the United States

An Alberici joint venture is constructing the $2 billion Olmsted Dam at a point on the Ohio River where more annual commercial tonnage passes than any other in the country. Olmsted Dam will significantly improve navigation and safety when it replaces Locks and Dams 52 and 53, which were originally constructed in 1929. The Olmsted Dam project includes installation of five 110-foot tainter gates, a 1,400-foot navigable pass section with 12 monoliths consisting of 140 wicket gates, and a fixed weir that ties the dam into the Kentucky bank.

Olmsted Dam building massive structures civil works project

Building massive structures on land and placing them in the water with incredible precision

Alberici is using an onsite concrete batch plant to produce several precast concrete shells, the largest of which weighs nearly 5,000 tons. The shells are approximately 100 feet wide, 100 feet long, and range in height from 30 to 75 feet. They are lifted by a massive gantry crane and moved onto a skidway, where they are then transported to the river’s edge. From there, a catamaran barge transports the shells out into the river where they are lowered onto an underwater foundation using high-tech sonar, video-imaging, and real-time kinetic GPS. Once the shells are set, tremie concrete is pumped into the area under the shells to form a continuous bond with the foundation.

Olmsted Dam innovative methods civil works project

Innovative methods and one-of-kind equipment

Olmsted Dam is being constructed using an innovative “in-the-wet” method, which eliminates the need for a traditional cofferdam and minimizes impacts to existing river traffic and the environment. The Alberici team is self-performing more than 95 percent of the entire project using highly specialized equipment for heavy lifting, pile driving, setting of large concrete shells, and scour protection of the river bed. The project’s 5,300-ton gantry crane is the largest of its kind and the “aqua-digger” excavator barge, which is capable of digging in 80 feet of water, is one of only two in the world.


Olmsted Dam industry leading safety civil works project

Industry-leading safety performance

In addition to being the largest civil works project ever undertaken by USACE, Olmsted Dam is the only Illinois construction project to ever achieve “Star” certification from the OSHA Voluntary Protection Program (VPP). OSHA VPP “Star” certification is among the highest honors for safety a project can receive.