The existing deck is in poor condition. The bridge was originally constructed in 1967, and the bridge deck is at a condition where patching and repair are no longer a viable option.
The cost of replacing the bridge would be over $400 million for bridge replacement versus the $90 million for deck replacement. By replacing the deck the life of the structure will be extended to over 50 years at a fraction of the cost for a bridge replacement. Over the past 40 years the substructure units have been repaired, along with some deck work. These past improvements have helped to maintain the structure in a condition that avoids the need for a costly replacement.
Both the I-75 over Rouge River and I-75 over Goddard Road bridge projects are significant projects that will require detouring SB I-75 traffic. To take advantage of this detour and to reduce future impacts to the public, improvements to this I-75 corridor have been packaged together.
The estimated construction costs are:
All three projects will be improved in the 2017 and 2018 construction seasons.
The size, type of work, and physical constraints of both the I-75 over Rouge River and I-75 over Goddard Road bridge projects limit the ability to perform this work without a freeway detour. Improving each bridge part-width would extend the length of construction, require multiple stages, put motorists in close proximity to construction workers, increase traffic delays, and increase the cost of the projects.
The SB I-75 detour option was selected because this option expedites construction, separates motorists from construction workers, and reduces the delays that would be experienced by the public
To determine the best option, 12 concepts were studied and a detailed traffic analysis was performed on viable options to determine the safest option that would minimize traffic delays and expedite construction.
Because of the significant size, and challenging physical constraints of the I-75 over Rouge River, a precast deck panel option will be provided as part of the design plans. With precast panels the deck could be replaced quicker with less disruption to traffic. The option of either a cast-in-place deck or precast deck allows contractors to determine the best approach based on the contractors available resources and their past experience.