If you plan to use the Windsor-Detroit Tunnel during the Detroit Grand Prix, the CEO of Windsor-Detroit Border Link said you'll need to be patient, and it wouldn't hurt to get a placard to put in your windshield.
The Grand Prix racetrack will include several downtown Detroit streets, so those roads will close leading up to the race and on race days.
This year's Grand Prix is from June 2 to June 4.
One of those roads that will close is Jefferson Avenue, the street U.S.-bound traffic first spills onto after leaving the tunnel plaza.
Carolyn Brown said Detroit Police officers would guide traffic around the closures, but a placard on your dashboard will signal to them you intend to return to Canada.
The placards will be available by request starting May 15, but as of May 31, workers at the tunnel will hand them out to every driver crossing the border.
Commuters can also find a copy of the placard on the tunnel's website that can be downloaded and printed.
Brown said drivers could enter the tunnel plaza without the placards. However, police might stop them. They would then have to explain their intention to return to Canada, complicating their return and adding extra time.
Tunnel Bus commuters should also expect changes.
The bus won't travel far beyond U.S. customs. There will be no stops in downtown Detroit. Instead, the bus will let passengers get off at the Tunnel Plaza before making a U-turn and returning to Canada.
Traffic should return to normal on June 5.