Project Location

Council Bluffs, IA

Project description

Innovative design, creative contracting and accelerated construction techniques kept one of the busiest interchanges in Council Bluffs open while drastically expanding its capacity. The 24th Street Bridge replacement was the first completed project in a series of projects to improve the capacity of the Council Bluffs Interstate System. The interchange serves major attractions, including a casino, arena and conference/event center, hotels and major shopping outlets. To serve the heavy daily traffic created by these nearby businesses,  24th Street and I-80/I-29 remained open during construction of the new bridge.

A project of this magnitude is typically constructed over two consecutive construction seasons, but due to the critical location of this interchange, traffic restrictions on 24th Street needed to be limited to a single season. The use of precast concrete deck panels and cost-plus-time bidding cut the construction duration in half while assuring the lowest price. Well-planned construction staging and intelligent transportation systems ensured that traffic capacity was maintained throughout the process.

By incorporating various innovative features, the Iowa DOT received partial funding for the project through the Highways for Life and Innovative Bridge Research and Development programs, thus freeing up state funding for other critical projects. The striking aesthetic features that were incorporated into the bridge design mimic the surrounding Loess Hills, creating a vision for area residents and a gateway into Iowa.

This project included:

• Reconstructing the bridge to make it longer in preparation for full reconstruction of the I-80/I-29 overlap section.
• Reconstructing 24th Street from just south of 27th Avenue to the I-80/I-29 eastbound ramp intersection. Following construction, 24th Street now includes two through lanes in each direction and accommodation for left turn lanes at the intersection on-ramps.

Project Schedule

Construction completed fall 2008.

Recognition & Awards

2009

• Associated General Contractors of Iowa, Iowa Quality Initiative Structure

PROJECT Gallery

project references

Project Name: I-29/I-80 at 24th St Interchange
Project Numbers: Bridge IM-080-1(308)2–13-78; Signals IM-080-1(326)2–13-78; Grade & Pave IM-080-1(334)2–13-78

Additional resources

Dual, Divided Freeway Configuration & Signage
Albert Paley's "Odyssey"