It’s been two days since an approximately 30-foot-long hole opened beneath Interstate 44 near Biddle Street and North Broadway, about a block from the Dome at America’s Center, forcing the closure of a major downtown St. Louis highway connection.
Officials said the portion of I-44 between the Stan Musial Veterans Memorial Bridge and the Poplar Street Bridge will remain closed for at least a week as workers stabilize bridge columns exposed by the collapse.
Here’s what we know – and what we don’t – about what caused the cave-in and how it will affect drivers in downtown St. Louis.
Officials are blaming aging pipes
St. Louis Water Division workers said broken water mains caused the collapse. Officials learned of a leak in a 20-inch water main late Friday night, and after the hole opened, other, smaller pipes broke, too.
At a news conference Sunday, Mayor Cara Spencer said the cave-in was a sign the city needs more money to replace its aging water structure.
“Situations like this, of course, remind us that our city’s great history comes with aging infrastructure,” she said, referencing a proposed water rate hike currently before the Board of Aldermen. The plan would raise rates by about 90% over the next six years, starting with an 18% increase on July 1, and create a reduced “affordability rate” for low-income residents.
“With the rates that we’ve had, we have not had the income necessary to do regular replacement of the lines,” Spencer said. “These lines were over 100 years old, and so you’re seeing decades of deferred maintenance.”
City workers initially had trouble shutting off water to the area, said Spencer Gould, deputy water commissioner, but the flow of water into the hole has since been stopped.
Spencer also touted directing millions in Rams settlement money to improving water infrastructure in the city.
Roads are set to be closed for at least a week
The hole opened just feet from support columns that hold up the elevated portion of I-44.
“Right now, that exposure is not severe, but the conditions on-site have the potential to continue changing,” said Jen Wade, area engineer for the Missouri Department of Transportation in St. Louis. “Keeping traffic off the bridge above reduces vibration of the columns, preventing further exposure from developing.”
I-44 westbound/I-70 eastbound is closed at Tucker Boulevard and the Stan Musial Bridge. Drivers should use the Tucker Boulevard exit or continue across the bridge on eastbound I-70, which remains open. The eastbound I-70 express lanes are also closed at Union Boulevard. There are no other ramps or lanes closed on I-70 in either direction.
I-44 eastbound/I-55 northbound is closed at the Poplar Street Bridge. All traffic headed into downtown should get off at the Park Avenue exit. Drivers coming from Illinois will not be able to take the Walnut Street/I-44 ramps and must continue east across the bridge.
Additionally, the ramp from I-64 westbound toward Walnut Street and I-44 is closed. Drivers who want to access downtown should use the 9th street exit.
Broadway Avenue, on both sides of the interstate, is closed at Biddle Street.
4th street is closed north of Washington Avenue.
The St. Louis Metropolitan Police Department is also telling pedestrians and sightseers to stay away from the area around the hole.
City of St. Louis Joint Information Center
Parts of Interstate 44/70 are closed downtown until further notice, officials said.
Officials say the bridge remains structurally sound
State Department of Transportation workers are reinforcing the area around the support column under the bridge so that traffic can start flowing while the hole underneath is fixed, Wade said.
“That column is in good condition,” Wade said. “There isn’t a problem structurally right now. The problem is that the sinkhole itself has not been stabilized, so we really want to make sure that nothing is going to change.”
Wade said she is optimistic the bridge will remain in good condition throughout the repair process.
Scientists with the Missouri Geological Survey have inspected the area. Spencer said preliminary findings indicate the collapse was caused by the failed pipes and not by geological conditions that could create additional problems beneath the bridge.
MoDOT recommends alternate routes
Wade said drivers traveling between I-44 and I-70 through the city should consider using Jefferson Avenue, Parnell Street and Salisbury Street.
“We anticipate detour traffic throughout the downtown area over the next coming days as motorists navigate throughout the downtown area,” said St. Louis Metropolitan Police Chief Robert Tracy. “Please plan ahead, look at those, look at those GPS websites, Waze, Google.”
Tracy said when he had to travel from the city toward north St. Louis County, he took Jefferson, and “made it almost in the same amount of time, maybe a minute later.”
What we still don’t know
It remains unclear who will ultimately pay for repairs, whether that responsibility falls to MoDOT, the city’s streets department or another entity.
Spencer said there’s no current estimate of how much filling in the hole and shoring up the column of the elevated highway will cost.
The timeline for reopening I-44 remains unclear.
“What we are doing right now is ensuring it’s safe,” Gould said. “Once it’s safe, we can make a determination of what repairs will be required. I think at this point we’re saying at least a week, but it hopefully would be done sooner, and could be done longer.”
