Merging Madness: Windsor launches campaign to educate polite motorists about Zipper Merging

When lanes are reduced, traffic experts say the most efficient way to keep the flow moving is for people to take turns squeezing into the remaining lane of traffic — and only at the last possible opportunity.

Zipper merge means everyone takes their turn, but frustrated drivers have to buy in


Windsor, Ont. officials are launching a campaign to toughen up polite Canadian motorists who meekly merge far to early — and fume at those who don't — causing avoidable congestion on roadways during the height of construction season.

The campaign will encourage drivers to embrace the "Zipper Merge" when approaching construction zones, maximizing both lanes of traffic for as long as possible before merging into a single lane. Similar campaigns have been launched in the U.S., but Ontario has yet to launch an initiative despite acknowledging "there may be benefits" to the approach.

Studies show the Zipper method can reduce congestion by as much as 40 per cent, but unless you've read those studies you might be inclined to shoot late mergers dirty glances while you white-knuckle the wheel.

"We get upset with them because we think they're breaking the rules," said traffic psychologist Dwight Hennessy. "That's when you get that battle that goes on, that the people in the main lane drive so close to the car in front of them because they're sending a message — 'I'm not going to let you in because you broke the rules.'"

The zipper merge is the proper way to merge, according to the Alberta Motor Association. (AMA)

It is the early mergers aversion to conflict that is the crux of the problem, said Hennessy, because they queue up early and often to avoid that sense of "panic" that comes with running out of lane and trying to merge into a line of uncooperative motorists. 

"The earlier they get in, the more they realize that they don't have to do that fight and battle with somebody else," he said. "They don't want to get into that merging lane and end up on that lonely island at the very beginning where they're merging and nobody will let them in so they get over much more early in the process and it creates one big long lane and then one lane that has very few cars in it." 

Zipper requires cooperation

Truck driver Keith Wheeler hopes Zipper Merging catches on — "It would be good for everybody," he said — and so does Young Drivers of Canada instructor John Grant, who expressed concern about a steep learning curve for local drivers.

"We're not educated on it around here," said Grant.

Windsor police Sgt. Steve Betteridge agreed, stressing successful Zipper Merging will require an education campaign and "a lot of cooperation among drivers."

Footage from Winnipeg streets shows delays when people don't zipper merge, and Winnipeggers weigh in on why they avoid merging lanes at construction sites. 0:59

City of Windsor staffers will roll out signs next week on E.C. Row Expressway between Howard Avenue and Walker Road after multiple motorists, frustrated by east-west congestion in the heat of the summer, implored City Hall to make the move.

"We're going to ask drivers to utilize both lanes of traffic up to the merge zone and then merge one car at a time," said Dwayne Dawson, the city's executive director of operations.

The move comes a few days too late for Hennessy, who tried the Zipper Merge on E.C. Row last weekend only to be frustrated by motorists in bumper-to-bumper traffic giving him the evil eye.

"It just made everybody slow down because the drivers that wouldn't let me in had to go to such great effort to not let me in," said Hennessy. "It ends up creating stopped traffic but in a real zipper it flows nicely."

Ontario, for its part, isn't actively promoting the Zipper Merge at this time, said Bob Nichols of the Ministry of Transportation.

"We have investigated the zipper (late) merge and found that while there may be benefits, it does require driver education campaigns to promote the late merge method," Nichols wrote in a statement. "MTO is continuing to evaluate the effectiveness of the zipper merge and other types of lane reduction methods to determine which concepts merit further research and trials."