ST. LOUIS — A large sinkhole collapsed an intersection in south St. Louis, just off Interstate 55.
The sinkhole opened at the intersection of Blow Street and Idaho Avenue this week. According to Nick Dunne with St. Louis Mayor Tishaura Jones' office, workers were alerted to a six-inch water main break at the intersection Tuesday.
"The sinkhole grew around the main break overnight, so our crews are investigating the cause of the sinkhole as they work to repair the water main," Dunne said in a statement.
By Wednesday morning, the sinkhole stretched about 40 feet in length and width and about 25 feet deep.
Spire said the gas lines in the area have been capped, and there are no outages associated with the street collapse.
Photos: Large sinkhole closes road near I-55 in south St. Louis
The Metropolitan Sewer District and City of St. Louis Water are investigating how the main broke.
"This area has very old infrastructure and unfortunately sometimes things break," Bess McCoy with MSD Project Clear said. "Whether it was the sewer that first had a collapse and then the water main broke, or the water main that caused the sewer main to break, this is all old infrastructure and unfortunately this is something that can happen."
To get to the bottom of what happened, MSD sent a robotic camera down their nearest pipe. The robot hit water, so crews had to bring in a vacuum truck to suction the water out.
"This is a very large sinkhole, something we are not used to seeing," McCoy explained. "In dry weather conditions like right now, you don't see something like this without a water main break."
Neighbor Iliyi Mendoca told 5 On Your Side the water went out Tuesday afternoon. She said the road always had a dip there.
"I'm glad I drove by before it sank because it would have been bad, we would have been under, inside of the hole," Mendoca said.
MSD updated 5 On Your Side Wednesday afternoon:
- The system appears to be intact in the area of the sinkhole.
- Inspection under the highway will continue tomorrow
- As long as the system is indeed intact, City Water's repairs will be quicker.
- MSD will have to reattach the washed out storm drains
There were 359 water main breaks in St. Louis in 2023, which was on par with previous years.
In a poll asking how money from the Rams relocation settlement should be spent, the top choice was to replace water mains in the city, with 9% of the total votes. The Board of Aldermen estimates this project could cost roughly $27 million.