After portions of St. Louis streets collapsed in north St. Louis and Lafayette Square last Friday, this weekend’s Go! St. Louis Marathon course is now slightly longer to avoid one of the areas.
A portion of the street crumbled into a 20-foot-deep hole near Cass Avenue and 18th Street. At the same time, part of the street collapsed into a 14-foot hole near Park Avenue and Dillon Street in Lafayette Square, taking a portion of the median with it.
Both happened on April 18, and construction crews from the Metropolitan St. Louis Sewer District Project Clear on Tuesday were actively working to replace 40 feet of underground sewer pipes at the north St. Louis site and about 14 feet of pipes at the one in Lafayette. The mains at both locations are 30-by-42-inch brick sewers, officials said.
Repairs could take up to a month at the Cass Avenue spot and two weeks or less at Park Avenue, according to the Metropolitan St. Louis Sewer District. The district hired outside contractors to help with repairs at Cass Avenue, and in-house construction teams are handling the one at Park Avenue.
Mona Vespa, president of the Go! St. Louis Marathon, said Tuesday that the Cass Street hole is about a half-block from the marathon path. But the smaller hole on Park Avenue is directly on the route.
“I don't necessarily feel comfortable having 10,000 people pounding on pavement a couple of feet away from that,” Vespa said. “And then also, because at any given point, MSD Streets Department could come in and need to start working.”
She said the adjustment made the route slightly longer — nearly a 10th of a mile.
“Instead of going in a straight line on Park Avenue, you're going a tiny bit each direction,” Vespa said. “And so it wasn't even a 10th of a mile, but again, for certification reasons, it does matter. … It's a little bit of a hassle, but it's not the end of the world.”
She said residents and businesses have been called to tell them about the small change. Vespa said she’s also had to resubmit paperwork for the race because even tiny changes matter for certification reasons.
Is it a sinkhole or a caved-in street?
While many people across the St. Louis region have called the recent street collapses “sinkholes,” representatives of the Metropolitan St. Louis Sewer District said they are technically “cave-ins.”
According to Sean Stone, a spokesman for the Metropolitan St. Louis Sewer District Project Clear, cave-ins are common in the city, and MSD investigates them often. He said it’s unusual to see large ones, and sometimes people call to complain about potholes, mistaking them for cave-ins.
So what’s the difference?
Stone said a sinkhole is a common natural underground occurrence in which water from rain or other bodies of water flows through bedrock and erodes it over time.
“Sometimes they get bigger, and sinkholes develop when that ground above collapses,” Stone said.
In contrast, the street cave-ins that happened in north city and Lafayette Square last weekend both had sewer lines that collapsed well below the street and washed away the sediment above it, Stone said. A common cause of cave-ins is the collapse of private laterals, or the pipe that runs from homes into the public sewer system.
The failure of private laterals was also the cause of a third street cave-in over the weekend near Tholozan and Potomac Avenue in south St. Louis. Stone said that MSD previously investigated street collapses there, but that the area is currently not under the district’s operation and maintenance.
“Those aren't our property,” he said. “Those are associated with the private properties they serve.”
Another cause of cave-ins is water main breaks, Stone said. And water mains are often located in the same areas as wastewater sewers.
Sewer mains in St. Louis have existed for over a century and, over time, developed flaws that allowed water to wash away some of the soil supporting the ground above them, he said.
“Some of our sewers date back 150 years or more,” Stone said. “So we've got a lot of very old infrastructure in the city of St. Louis. It was built well, [and] we take care of it, but everything wears out eventually. So the biggest factor is time. Big rains don't help.”
MSD officials say they don’t yet have an estimate for the cost of repairs at the two holes, being that both are emergency fixes and require more investigation to determine the full extent of damages.
“To my knowledge, the city does not have any responsibilities for either cave-ins we’re working on, so there should be no direct costs for the city,” said Bess McCoy, another MSD spokesperson.
Just ‘fix it!’
Whether they’re technically called sinkholes or cave-ins, some city residents say, doesn’t matter.
“I just want them to fix it, I don't want to talk. Fix it!” said 70-year-old Linda Warren, who lives a block from the cave-in site in north city. She said she’s lived in the area off and on for about 20 years.
Another north city resident, Shelitha Womack, 49, said the street caved in the day after her birthday. She lives at Cass Avenue and 18th Street, across from the site of the street collapse.
She said that there has been a slight dip in the street right where the hole is, since at least last summer.
“It was starting to be like a roller coaster,” Womack said. “At first it was just like a little hump, and then as the days was going on, it was starting to get deeper and deeper.”
Womack expressed concern about the city’s former use of underground brewery caves, which she believes could have left tunnels underground. The Lafayette Brewery Cave, primarily used in the mid-19th century, is a historic underground cave system that was used by breweries and other businesses for the storage and lagering of beer.
“It just made me think it's tunnels up under us, too, and when is the ground going to give up under us? That's scary,” she added. “That's real scary.”
She said the city was slow to put up street signs when the area first collapsed last weekend. A couple of cars crashed into a barrier set up around the hole, but they drove away without reporting the incident, Womack said.
Rosalyn Lumpkins, 39, corroborated hearing vehicles hit the barrier over the weekend. She's lived in the area most of her life with her mother, Viola, 79. She said it’s no secret that the streets in St. Louis need to be addressed, and Cass Avenue in particular has often been a problem, she said, though the neighborhood was remodeled a few years ago.
“Hopefully, we got the right mayor that we put in there. She's going to take care of us, that's why I voted for her,” Lumpkins said.
