The year before, the United States Congress passed a law allowing private citizens to build a bridge as a business venture.

Moline refused to grant the franchise for the bridge and the early years of the Great Depression made it difficult for the businessmen to finance it on their own without the city's help.

[5] At the end of World War II, traffic increased substantially on the bridge, prompting studies for a possible widening of the crossing to four lanes.

New loop ramps were constructed on the Bettendorf approach to allow for increased traffic to more adequately cross the bridge.

When this goal was met, the US government bought the bridges on December 31, 1969, and work began on the project in November 1971, with the removal of the toll plazas.

The road capacity was temporarily restored to two lanes as reconstruction work required the closure of one span at a time.

Completion of the project was delayed due to funding issues caused by the Vietnam War.

The study claimed that the I-74 Bridge project would spur economic growth, create construction jobs, reduce traffic backups, and improve air quality.

Former Illinois Governor Pat Quinn said the state is committed to bridge improvements to help traffic flow and "boost economic growth in the region".

By 2012, the Illinois Department of Transportation budgeted more than $34 million for engineering, design, and land acquisition for the new bridge.

Final design was completed by Modjeski and Masters in association with Alfred Benesch & Company.

By 2019, construction on the new westbound span was long underway, however it required demolition of the existing eastbound viaduct in Moline.

[21] The contract for deconstructing the suspension bridges was awarded in September 2022 to the Helm Group, the company who had a part in constructing the new viaducts in downtown Bettendorf.

[23] On June 18, 2023, the trusses of the deckless Illinois bound span were detonated with explosives, leaving only a small part of the bottom superstructure to be removed in a future demolition.

[24] By July 2023, the Iowa bound bridge's superstructure had been fully removed, its steel was then sold as scrap metal.

[27] The fourth and final implosion occurred in the early hours of February 18, 2024, with the Illinois sides anchorage being impolded.