The governors of the US states of Kentucky and Indiana and the mayor of Louisville outlined savings that could be made in several key areas. Aspects to explore include rebuilding a major junction in the existing location rather than moving it south and reducing the East End bridge from six lanes to four lanes, with the option to add two lanes later if traffic demand warrants.

In addition, the Louisville & Southern Indiana Bridges Authority will explore other cost-saving solutions in design, construction and financing by soliciting private-sector ideas at an industry innovation forum next month.

"The key to our success moving forward is a lean design that meets our needs at the lowest cost," said Indiana governor Mitch Daniels. "Our ability to move with creativity and innovation will reduce costs and, ultimately, the tolls to make this project happen. It's time to unleash the power of the private sector."