All lanes of southbound I-55 between Butler Hill Road and 141 are now open to traffic, MoDOT announced Thursday morning. The northbound lanes remained open during the closure and will remain open.

“The cresting of Meramec River is the beginning of the light at the end of the tunnel,” said MoDOT-St. Louis Asst. District Engineer Tom Blair. “This crest means there could possibly be other roads opening soon.”

Route 141 at Romaine Creek and Route 21 at the Meramec River are still closed at this time.

WATCH LIVE: Looping Radar over the St. Louis area

Tesson Ferry (Route 21) at the Meramec and Route 141 at Romaine Creek have also closed due to flooding.

"You all are going to have to decide what side of the river you want to be on when you go to bed tonight," said Greg Horn, MoDOT's district engineer of the St. Louis Region during a Tuesday afternoon press conference.

The Meramec River near Arnold is expected to crest 10 a.m. Wednesday at 46 feet.

Anyone who needs to travel between southeast Missouri and St. Louis will have to find routes through Illinois.

Interstate 44 west of I-270 remains closed. 5 On Your Side is continuously updating a list of major road closings. You can see the full map of road closure from MoDOT at, or call 1-888-ASK MODOT (275-6636).

Most of the major routes are not expected to reopen until late in the week. Once the water recedes, MoDOT will have to inspect the pavement and bridges for safety before the roadways can reopen.

Volunteers worked for hours side by side to build a wall of sandbags at a business park off Meramec Bottom Road.

“Today is a really a game of inches,” said Michelle Anselmo, the Vice-President of Mike Martin Media.

The production company and studio is just one of several businesses in the path of floodwaters of the swollen Meramec River.

Many of them were also damaged during the floods of December 2015.

“If I could get those kind of odds at the casino, I’d be doing pretty good,” joked volunteer Jim Moore.

The last time around, the river left about a foot and a half of water inside several businesses, causing $300,000 in damage just to the structures alone.

This time, all the owners are cautiously optimistic that won’t be the case.

“We are trying to fight it, but given the prediction, it could get into the office space,” Anselmo said.

But stopping the rising floodwaters isn’t the only concern.

Moore said, “We have to get it all done before the road closes.”

“Decide which side of the river you want to sleep on tonight because you’re not getting to the other side,” Moore said.

And in some cases, families will be torn apart.

“I live in Eureka. My family is sandbagging there. I’m here at the business. I many not see them til the weekend,” Anselmo said.

Safety officials encouraged people to get where they need to be for the next few days sooner than later.

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