I-74 Iowa-Illinois Corridor

I-74 Corridor Study is part of a three-pronged regional strategy for improving access across the Mississippi River in the Quad Cities. Other strategies are the removal of tolls from the Centennial Bridge (accomplished in 2003)and future construction of a new bridge connecting Bettendorf and East Moline. These strategies are the result of the 1998 Quad Cities Mississippi River Crossing Study. Although the I-74 project is independent of other planned improvements, it is compatible with the region’s strategy for improving travel across the Mississippi River.

No. This project involves a comprehensive look at the travel problems along I-74 between Avenue of the Cities in Moline, IL and 53rd Street in Davenport, IA. The objective is to develop a solution that will not only improve travel through the corridor, but will also improve access to adjacent communities. Solutions include widening and realigning I-74, modifying the location and design of interchange ramps, providing enhanced connections for alternative transportation modes, and implementing transportation system management strategies.

The study will be completed in two parts. Part I, included the preparation of a Draft Environmental Impact Statement (EIS) and selection of a preferred alternative for the I-74 corridor. Part II refined the recommended solution and concluded with the preparation of a Final EIS and the Record of Decision from the Federal Highway Administration.

• 1998: Mississippi River Crossing Study
• 2000: I-74 Corridor Study began
• 2003: Draft Environmental Impact Statement completed
• 2005: Preferred Alternative identified
• 2006: Main Span Bridge Type chosen
• 2007: Preliminary Engineering completed
• 2009: Final Environmental Impact Statement completed and Record of Decision received from the FHWA

Travel through the I-74 corridor is often restricted due to rush hour congestion and blockages due to stalled vehicles. Driver handling problems are caused by design issues, including short acceleration and deceleration distances, roadway curves, limited sight distance, closely spaced ramps, and the absence of shoulders on the narrow Mississippi River bridges. These conditions result in crash rates in parts of the corridor that are almost 3-times the national average.

A common misperception is that rush hour congestion is the problem in the I-74 corridor. Actually, the congestion is a symptom of the design and operational issues that exist. The I-74 Corridor Study considered a variety of non-roadway alternatives, including transit features, bicycle and pedestrian facilities, and transportation management strategies; however, none of these solutions correct the problems in the I-74 corridor. Therefore, while such improvements will be considered as part of an overall strategy, they cannot be considered "Reasonable Alternatives".

The Mississippi River bridge design itself is a major contributor to the congestion problems with its narrow width and lack of shoulders. Further, the State Street and River Drive ramps cannot be substantially improved without widening the existing bridges. While outdated ramp design, including closely spaced ramps and short acceleration/deceleration distances, is a problem throughout the corridor, addressing the ramps while ignoring the other design issues would do little to correct the overall operational problems in the area.

Contrary to perception, there is not an appreciable amount of interstate through traffic on I-74 (traffic which begins and ends outside the corridor). Thus, diverting interstate traffic would do little to reduce traffic volumes. In addition, the diverting of traffic would not address the cause of the problem--the need to update design features.

While it is probably physically possible to widen the bridges, it just isn’t very practical to do so. The additional load that the structure would need to carry (both structure and vehicles) would necessitate strengthening or replacing the complete deck structure, replacing the main suspension cables or augmenting the existing ones with companion cables, strengthening the towers and foundations and rebuilding / enlarging the cable anchorages. If each bridge is put out of service while work on the individual structure is performed, I-74 would be reduced to one lane in each direction, augmenting the traffic problems. For both bridges to remain in service during peak hours, the construction schedule would be extended significantly. The cost of such a conversion would likely be in the same range as that of building a new bridge, and while the resulting bridge would be structurally adequate, the resulting bridges would be compromised in terms of appearance, functionality and future maintainability.

The decision on the fate of the existing bridges was made during the FEIS phase, following public input. Options to keep the bridges in place were considered, including an option to keep one of the bridges in place for an alternative transportation use (bicycle/pedestrian). However, in order for the alternative transportation use option to be implemented, a public agency must be willing to assume jurisdiction of the bridge, and be responsible for its ongoing maintenance. Involved local agencies have indicated that they are not interested in assuming future responsibility for the existing bridge. Options to use the bridges for other vehicular purposes were eliminated during the FEIS phase of the study.  With the roadway and bridge type selected the existing bridges would be dismantled as part of the construction of the new bridges.

The project will result in some impacts on environmental and cultural resources in the area. The alignment alternatives were, in part, chosen due to their ability to avoid critical cultural resources; however, the alignment that impacts between 4 historic resources.

Now that the Final EIS and the Record of Decision are complete final design can begin.  Funding is secured through final design and through some of the right-of-way acquisition. Funding must still be secured for the remaining right-of-way acquisition and the actual construction of the proposed improvements. Once funding is secured and final design and right-of-way acquisition is complete (final design alone is a three year effort) major construction efforts on the new Mississippi River Bridge and approaches could begin. However, there are independent projects within the I-74 corridor that are already in Iowa’s Five Year Transportation Improvement Program.  These include the Lincoln Road bridge over I-74 in Bettendorf  and the 53rd Street interchange in Davenport.

This project considered a number of improvements for the corridor including, but not limited to:

	Roadway capacity improvements. Capacity improvements allow more vehicles to travel on the road. These improvements included the expansion of the roadway with additional travel lanes, and improvements to interchanges and intersections.
	Roadway design improvements. Design improvements enhance the operation of the facility. These improvements included improving the alignment of the roadway, providing wider travel lanes and shoulders, and improving the location and design of on- and off-ramps.
	Transportation system management. These actions are usually designed to improve the operation and performance of the existing system, and included intersection improvements that accommodate turning movements, travel advisory signs, and traffic signal coordination.
	Transit improvements. These actions could include improvements to the regions’ transit systems. Improvements could expand services, or enhance existing services by providing features such as bus turnouts or more frequent service.
	Bicycle and pedestrian improvements. There are a number of bicycle and pedestrian facilities in the project area. Opportunities to enhance connections across or along highways in the study area were considered. This will include options to improve bicycle and pedestrian access across the Mississippi River.

The study team developed a broad public coordination and communication program to ensure that community values were considered during the study. Some of these activities included:

• continuous two-way dialog throughout the study with area community officials
• thorough review of local land use and comprehensive plans, county plans, and regional plans to ensure consistency with alternative solutions
• input from community and neighborhood groups on local issues
• consideration of community issues in the development and evaluation of alternative solutions for the corridor

Decisions for this project were made by the Iowa Department of Transportation and Illinois Department of Transportation, who have jurisdiction of the I-74 corridor. Decisions were made in an informed manner, with input from all interested parties.