Clean Currents 2022

McNary Dam: Design-Build Solution Delivers Critical Structural Upgrade of Concrete Beams

McNary Dam spans 1.4 miles across the Columbia River at the Oregon-Washington border 185 miles east of Portland. The Dam was built from 1947 to 1954 with the power generation units coming online in 1957. The powerhouse at McNary consists of 14 generators that create 980 megawatts of power capacity, which supplies power to 685,000 homes

As part of future expansion at the Dam, US Army Corp of Engineers (USACE) determined that a new gantry crane would need to be installed. The superstructure holding the crane was analyzed as part of the project, and it was determined that 48 concrete beams would need to be strengthened to accommodate the additional weight of the new crane.

USACE determined the best path to achieving their project objectives, including scope, schedule, and budget, was to utilize design-build delivery. Design-build would entrust those experienced in beam enlargement to develop the best approach to perform the project. In fact, it did as the value-add design that streamlined the project took the original design concept of a 3-sided enlargement and converted it to providing all the strengthening required with a 1-sided enlargement.

This poster provides detailed information on the project from procurement to completion, including the innovative design utilized and how it shortened the project by 3 weeks. Attendees will learn state-of-the-art for concrete strengthening, best practices, and lessons learned overcoming challenges during the McNary Dam Beam Enlargement project.

Presenter Information

Jay Thomas

Jay Thomas
Vice President
Structural Technologies
Poster Presenter