The problem has become so bad in Saskatoon that one city councillor has proposed a ban on all future drive-thrus.
A report is looking into whether such a plan would work.
City transportation manager Angela Gardiner said she's not sure a ban is the best solution. But the problem does need to be addressed.
"The demand at Tim Hortons drive-thrus is increasing across the whole country, so everybody is faced with this."
Gardiner said the dilemma was brought up at a national transportation engineering conference last year. Traffic numbers for Tim Hortons drive-thrus greatly exceed the average for other fast-food outlets in Canada.
She said two Tim Hortons locations in the city are the most problematic.
A double-wide drive-thru was added to the busy restaurant off 8th Street. And a traffic barricade was installed at the site near Idylwyld Drive, where patrons had illegally been turning left into the parking lot and lining up through the major intersection.
Gardiner said city officials are also working with the owners of new Tim Hortons outlets, before they build, to map out appropriate drive-thru space. One owner actually abandoned his chosen location when both sides couldn't agree on the design.
Staff Sgt. Grant Obst, head of the city police traffic unit, said the drive-thrus haven't caused police serious concerns.
"It would be something that would affect patience and frustration of a motorist rather than safety," he said. "But sometimes a frustrated motorist can become dangerous."
Last month, police in Grande Prairie, Alta., were called to a Tim Hortons when a customer in its drive-thru line pulled a gun.
The driver allegedly cut in line and brandished the weapon when confronted by another patron. Police later stopped his vehicle and found a pellet gun.
Obst said officers in Saskatoon have not responded to similar coffee-rage incidents.
"We've had an individual get mad and throw a bit of a temper tantrum. But as far as actual violence or actual weapons, we're not seeing that in Saskatoon. Thank God."
— By Chris Purdy in Edmonton
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