Built in 1921, the Emsworth Main Channel Dam is one of the oldest dams still operating along the Ohio River’s inland waterway. Despite the various measures taken to protect the dam’s apron from undermining and dissipating energy, the original and subsequent scour protection methods have failed to perform adequately. As a result, the dam is considered one of the most unsafe navigation dams in the Pittsburgh District.

This $85.5M project was a testament to our team’s ability to manage complex, large-scale projects. We utilized innovative in-the-wet technology to provide design services for two dams, two fixed-span service bridges, and abutments. Our team also ensured that the dams’ basic flood control and navigation functions were maintained during construction.

Our design plan involved connecting pre-existing and newly constructed walls using both upstream and downstream grout bags. We created detailed bedding schemes for various subsurface conditions, established installation tolerances, connected adjacent grout bags, and specified the necessary grout and grout bag materials. In addition to these elements, our design also included dredging, bedding, and riprap. One of the key challenges was to develop a construction sequencing plan that would enable safe construction while maintaining navigation and river flows. As a result of our team’s innovative problem-solving, use of the river remained uninterrupted during construction.

To meet the bid solicitation deadline, a ten-month fast-track schedule was maintained. The Contract Documents provided for bidding contain multiple Awardable Options to accommodate funding limitations. Our firm provided EDC Services through 2010, including meetings, site visits, submittal reviews, and contractor design reviews.