|Interstate 74 Bridge|
The Interstate 74 bridge as seen from the Iowa side of the Mississippi River
|Official name||Iowa-Illinois Memorial Bridge|
|Carries||4 lanes of I-74 / US 6|
|Locale||Bettendorf, Iowa and Moline, Illinois|
|Design||Twin suspension bridges|
|Total length||3,372 feet (1,028 m)|
|Width||27 feet (8 m)|
|Longest span||227 m|
|Opened||November 1935 (northbound)
December 1959 (southbound)
The Interstate 74 Bridge, originally known as the Iowa-Illinois Memorial Bridge, and often called The Twin Bridges, or the I-74 Bridge, is a pair of suspension bridges that carry Interstate 74 across the Mississippi River and connect Bettendorf, Iowa and Moline, Illinois. It is located near the geographic center of the Quad Cities.
The bridge was designed by engineer Ralph Modjeski. The first span opened in 1935 as a toll bridge. In 1959, an identical twin span was added to satisfy increased traffic. The twin spans were upgraded to carry interstate traffic in the mid-1970s. Built for a daily crossing of 48,000 vehicles, the daily average is 80,000, making it by far the most traveled bridge in the Quad Cities. Both the Interstate 80 and 280 bridges are up to Interstate standards, while the Interstate 74 Bridge is functionally obsolete and was not built to Interstate standards, as it has two narrow lanes, no shoulder, and a 50 mile-per-hour (80 km/h) speed limit.
I-74 bridge replacement 
The I-74 Corridor Study is underway to study replacing the bridge with a larger one with 4 lanes in each direction. The study claims that the I-74 Bridge project would spur economic growth, create construction jobs, reduce traffic backups, and improve air quality.
Funding for the construction of the new bridge has been earmarked for $22 million in 2017 and $50 million in 2018. Illinois governor Pat Quinn said the state is committed to bridge improvements to help traffic flow and "boost economic growth in the region."
As of 2012, the Illinois Department of Transportation also budgeted more than $34 million for engineering, design and land acquisition for the new bridge. The portion of the bridge spanning the Mississippi River is estimated at more than $700 million, while the project as a whole, including all approach routes and connectors, is estimated at more than $1.3 billion.
While on a tour at the base of the bridge in Bettendorf in May 2012, U.S. Transportation Secretary Ray LaHood said that, in comparison with other bridges that he has seen in other states, the I-74 Bridge is one of the worst he's seen.
See also