St. Louis motorists had a mostly trouble-free drive during the first commute of the latest Highway 40 closure.

For the second time this year, officials at the Missouri Department of Transportation said motorists sidestepped widespread congestion while a stretch of Highway 40 is being rebuilt — this time between Interstate 170 and Kingshighway.

Despite concerns that drivers hadn't prepared for this highway shutdown, transportation officials said traffic flowed smoother than expected Monday on many of the region's highways.

Crews reopened the western section of Highway 40 (Interstate 64) two weeks ahead of schedule late Sunday night, after closing the eastern section on Saturday. The state is rebuilding about 10 miles of the interstate highway at a cost of $535 million.

Overnight snow and ice were blamed for most of the traffic problems during the Monday morning commute. Icy road conditions contributed to some traffic accidents and slowdowns.

"For the most part, the traffic out there that was a problem was because of the weather," said Pete Rahn, director of the Missouri Department of Transportation.

Traffic was lighter than normal on every road but Forest Park Parkway, transportation officials said. Morning backups on Interstates 70 and 270 were due to crashes. On westbound Interstate 44 near downtown, police closed two lanes to protect an injured dog from traffic.

The problems on Forest Park Parkway were during rush hours. Traffic on some stretches was 60 percent above normal. In the morning, engineers adjusted signals twice along Forest Park Parkway so green lights would last longer for parkway traffic, but at the expense of drivers on Big Bend and Skinker boulevards.

Forest Park Parkway cannot move any more traffic during the morning rush, said Todd Waelterman, St. Louis streets director. "When you get to Big Bend and Skinker, those two signals can't handle any more volume," he said.

Waelterman recommended that drivers use Page Avenue instead.

Lesley Hoffarth, the I-64 project director, said traffic on the newly reopened stretch of Highway 40 was significantly lighter than before the reconstruction project began.

Transportation officials added that there was "significant congestion" Monday night at Highway 40 at Brentwood, Interstate 170 at Eager Road, and Brentwood at Manchester.

Motorists were still getting used to some of the new interchanges along the rebuilt section, Hoffarth said. One example is Lindbergh Boulevard.

"People were used to having to choose their exit by whether they were going north or south," she said. "Now people exit and then can choose whether they go north or south through the single-point intersection."

The overpass at McCutcheon Road is still closed and will reopen next month, said Dan Galvin, spokesman for Gateway Constructors. Crews need to finish up sidewalks and concrete barriers, which were on hold until Richmond Heights finished its improvement project on McCutcheon. The remaining work is weather dependent, Galvin said.

Monday's weather caused Gateway Constructors to cancel its work. Crews had planned to close Laclede Station Road under the highway and begin demolishing the overpass. That work will begin today.

Hoffarth warned that snow and possible freezing rain are in the forecast before today's morning commute.

St. Louis motorists were credited for keeping traffic tie-ups to a minimum by finding alternate routes and changing their commute times after the first section of Highway 40 closed 11½ months ago.

The eastern half of Highway 40 is scheduled for reopening Dec. 31, 2009.

Local commuters ran into some traffic on Monday but they mostly blamed the weather.

Doug Mendoza, an engineering manager from Chesterfield, found his commute to work near downtown St. Louis 10 minutes slower than normal, because of the weather. He drove the new stretch of Highway 40 to northbound I-170 to eastbound Interstate 70 to Grand.

"I-170 was about empty," he said. "I had the impression that people were not necessarily taking the new section (of Highway 40) because they were worried. It was wider and straighter."

Bill Fink, a technology consultant from Belleville, said drivers were driving too slow. His morning commute to Creve Coeur took 1 hour, 45 minutes — one hour longer than normal.

"My drive in to work was nothing short of sucky. All the sleet this morning made it worse," Fink said. "It was totally weather-related because of slushiness and people were driving 40 miles an hour and being overly cautious. This is the first winter weather of the season. They're going to need to get used to it."

Cathy Buckley of Manchester, a training specialist at Enterprise Rent-A-Car in Clayton, didn't experience any difference in her commute to work.

"There was no one on the road," she said. "Because of the school closings, I'm not sure it's going to be a realistic estimate of what the time is going to be to get here on a 'normal' day."

Staff writers Greg Jonsson, Tim O'Neil, Kim Bell, Paul Hampel, Michele Munz, Matthew Hathaway, Shane Anthony, Phillip O'Connor, Steve Giegerich, Tim Barker, Tim Bryant, Joe Crawford, Margaret Gillerman and Denise Hollinshed contributed to this story.

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