Update 11:10 a.m. Friday - According to the Missouri Department of Transportation, as of 10 a.m. Friday, "Both directions of Interstate 44 in St. Louis County are now open between mile marker 253 and 274. Interstate 55 at the St. Louis County and Jefferson County line opened earlier today. All interstates in Missouri are now open to traffic.
"In the St. Louis area, Route 21 and Route 30 remain closed at the Meramec River and Route 141 is still closed at I-44 and at Route 21."
The death toll in Missouri and Illinois reached 24 by Friday evening. The Mississippi River was expected to crest in Cape Girardeau Saturday.
Original article - The water reached its peak in Valley Park early Thursday morning and hours later in Arnold, shattering flood records set back in 1982.
Although Missouri Department of Transportation sandbagged along Interstate 55, officials had to shut down the roadway early Thursday.
"We did everything we could to keep it open," said, MoDOT district maintenance engineer Mark Croarkin. "We had sandbagging efforts all night. If we hadn’t been sandbagging we would have people trapped."
Shortly after 3:30 p.m., the Department of Transportation said it would open two northbound lanes of Interstate 55 by 5:30 p.m. Dec. 31 at the Meramec River, mile marker 193.
As Croarkin said Thursday morning, about six to eight inches of water covers the rest of roadway, which is closed at the St. Louis County and Jefferson County line at the Meramec River. Sandbags are holding back up to three feet of water, and he said the department is bringing in additional pumps to keep it back.
The Meramec River reached 47.2 feet in Arnold mid-morning on Thursday, more than 23 feet above flood stage. The crest was two feet higher than the previous flood record.
About 100 homes flooded in the northern section of the town, according to Arnold Police Captain Robert Ruckman.
"We don’t have an exact count," he said, "but I believe the assessment is going to start either today or tomorrow."
The water is expected to recede fairly quickly, according to U.S. Army Corps of Engineers hydraulic engineer Russell Errett. He said levels had dropped 13 feet in Sullivan, seven feet in Union and more than three feet in Eureka.
"Valley Park should start falling off pretty quickly, probably later today it should be falling off pretty rapidly," he said, "and then Arnold will fall in behind it several hours later."
The river reached 44.1 feet at Valley Park early Thursday, 28 feet above flood stage and more than four feet higher than the previous record. Officials in Valley Park had worried that a new levee might be overtopped, but while the water came close, it did not spill over.
"We had our flood fight teams out there and they added some extra measures to ensure in case the forecasts came in wrong," Errett said.
Sewer treatment plants
Still, a temporary levee Metropolitan St. Louis Sewer District workers set up around a plant in Valley Park breached early Thursday, forcing a shutdown. It’s the second plant MSD has had to close this week. Its plant in Fenton was closed after being pushed over capacity late Monday night.
"We have temporary pumping set up and our top priority is to get the pump station operational again and then get the treatment plant up and operation," MSD spokesman Sean Hadley said.
The Valley Park treatment plant handles about 21 million gallons of wastewater a day that is now being dumped into nearby streams and the Meramec River. The Fenton plant handles 6.75 million gallons daily and is also diverting the wastewater to creeks, streams and the river.
Hadley said there is no timetable on getting the plants back open as of yet.
"It’s a waiting game now; wait for the waters to recede so that we can get in to access the severity of the damage to both plants," he said.
People are cautioned to avoid contact with flood waters, as they can carry harmful bacteria. When residents are cleaning up flood damage indoors, the CDC recommends wearing rubber boots, gloves and goggles.
The interstate remains closed between Bowles Avenue and in St. Louis County and Route 100 in Franklin County.
MoDOT shut down the roadway early Wednesday morning due to flooding on the Meramec. At a late-afternoon press briefing Thursday, County Executive Steve Stenger said the water depth at I-44 and 141 was between 18 and 20 feet.
Officials said they don’t expect I-44 to reopen until Friday at the earliest.
Stenger also praised first responders, noting there had been no loss of life or significant injuries in St. Louis County.
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Donna Korando contributed to this article.