Thousands of drivers were forced to take detours and part of the Mississippi River was shut down for shipping.
The bridge, leading into Memphis in the southwest corner of Tennessee, was shut down on Tuesday afternoon after inspectors found a “significant fracture” in one of two horizontal steel beams stretching across the river. Each beam is 900 feet long. The beams are essential for the bridge's structural integrity, according to Lorie Tudor, the director of the Arkansas Department of Transportation.
The damage comes as the Biden administration and congressional Democrats are negotiating with Republicans over Mr Biden’s $2.3tn infrastructure proposal. Republicans’ first counterproposal measured $568bn.
Senate Minority Leader Mitch McConnell has said he thinks the package should cost between $600bn and $800bn. While Democrats want to raise the corporate tax rate to pay for the investments, Republicans have mainly argued for user fees.
Both the transportation departments of Tennessee and Arkansas assured people that the 48-year-old, 1.8 mile long bridge would be safe before it once again opens to traffic.
“This fracture had the potential of becoming a catastrophic event that was prevented by our staff’s diligent effort in managing our bridge inspection program,” Ms Tudor said.
Traffic was instead sent to the next bridge about three miles south, where the 71-year-old Memphis and Arkansas Bridge crosses the river. It has four lanes compared to the six lanes of the now-closed Hernando de Soto Bridge upstream.
The nearest river crossings to the Memphis and Arkansas Bridge are now about 100 miles to the north and 60 miles to the south.
Traffic on the river was also halted until further notice. The Coast Guard said that 16 tug boats pulling along more than 220 barges were stuck in line on Wednesday.
DeWayne Rose, emergency manager in West Memphis in Arkansas, just across the river from Memphis, Tennessee, said: “People around this area are used to lane closures, they’re used to construction, they’re used to shutdowns, and I think everyone is just a little on edge because of the uncertainty of the time frame of this."
Paul Degges, the chief engineer for the Tennessee transportation department, said determining whether the damaged bridge can hold its own weight and the weight of construction crews can take days.
Officials said the state of Arkansas is in charge of inspections, while Tennessee manages maintenance and repairs.
“Certainly, it's plausible that this could be months rather than weeks,” Mr Degges told reporters. “We are hopeful that we can find a solution that would allow us to proceed with some opening of traffic, but right now we just don’t know.”
Memphis Democrat Steve Cohen said: “It’s fortunate that routine inspection averted a potential disaster, but the state of our crumbling infrastructure is deeply troubling."
Mr Cohen said he would push for improvements to the I-40 bridge to be a part of the Biden infrastructure package.
In the 2020 National Bridge Inventory report, the Federal Highway Administration said the bridge’s structural evaluation checked out “somewhat better than minimum adequacy to tolerate being left in place as is”.
Inspectors also found that height and width clearances for oversize vehicles were “basically intolerable requiring high priority of corrective action”.
Arkansas officials said the crack was not present during the last inspection in September 2020.
The bridge opened in 1973 and carried an average of 35,000 vehicles a day across the river during the course of last year, the report states. But Mr Degges said the real number is around 50,000 vehicles a day.