Flatiron managed the joint venture team that designed and built the John James Audubon Bridge, a cable-stayed bridge across the Mississippi River in Louisiana. The bridge replaces a ferry system that connected St. Francisville with New Roads just north of Baton Rouge, Louisiana.

The cable-stayed portion of the bridge from expansion joint to expansion joint is 3,186 feet, with the main cable-stayed span stretching 1,583 feet, the longest cable-stayed main span in North America at the time of construction. The two towers reach 520 feet and are anchored by 42 drilled shafts, 180 feet into the riverbed. The bridge is designed to last 100 years and withstand barge impacts, hurricane winds, and scour.

Flatiron’s design-build contract also includes the approaches and 12 miles of roadway that tie the bridge into US-61 and Louisiana Route 10, including seven bridges and a railroad spur to serve a coal-fired power plant.