PEVELY, MO (KFVS) - Everyone hates to wait in traffic, but the Missouri Department of Transportation is trying out a merge method it said can potentially cut the length of traffic backups by 40 to 50 percent.
It's called the "Dynamic Zipper Merge," and hinges on three things: traffic using all open lanes right up to the merge point, taking turns and knowing what's going on. The latter has proven to be the most difficult obstacle.
MoDOT engineer Judy Wagner is over Jefferson and Franklin Counties. A zipper merge system is in place in her district on Interstate 55 near Pevely.
"Basically, what it does is it takes all the traffic that is coming at a work zone – and it tries to get them to go all the way to the end of the merge zone and then connects them like a zipper," said Wagner. "One car takes a turn, then the other car takes a turn, so that everyone can move at a slow pace all the way thru the congestion and then merge through the narrowed area and continue on their way."
In theory, it sounds great – but there's one problem. Not many people seem to understand what's going on in the Pevely zipper merge zone.
To many drivers, the idea of someone waiting until the last possible second to merge sounds rude, not efficient.
Jackson driver Carson McCord said he probably wouldn't be happy if someone merged in front of him as he waited his turn to get through the merge point.
"I'd probably honk my horn," said McCord.
"I would get aggravated," said Jerry Sides of Jackson. "But what can you do? That's gonna happen."
Wagner said that is the reason Missouri drivers are still seeing traffic backups at merge points in construction zones.
"It's a change of culture for our Missouri motorists," said Wagner. "Especially because they are used to waiting in the long line and waiting their turn. Now we're asking them to go ahead – take all the lanes up to that point of constriction and then merge at that point."
When Heartland News drove through the Pevely merge zone there were signs posted saying "use all lanes to merge point, then take turns." However, as we neared the point of constriction, after waiting 30 minutes, the right lane was wide open. The left lane was stop-and-go, bumper-to-bumper traffic.
McCord said he had traveled through the Pevely zipper merge zone, and wasn't impressed.
"It does not work," said McCord. "I've been through it coming back from Cardinals games, coming back from tournaments, it does not work. People try and keep on trucking and those people just get stuck and they'll try and have three people at once try to cut in front of them, and then they get mad and people behind them get mad."
Wagner said the Zipper Merge is effective if everyone follows the rules and is willing to take turns. But, she said it may take time for the motoring public to become educated on the process.
"We have to get to that culture where this is what you're supposed to do, so I don't wait 38 minutes in this delay," said Wagner.
According to MoDOT, the zipper merge is best applied in situations where traffic is very heavy, stop and go, or moving very slowly. If traffic is flowing freely at or near the speed limit with a lot of space between vehicles, MoDOT said it's best to merge early the old-fashioned way.
Learn more about the zipper merge in a video made by MoDOT to explain the merge technique.