During high winds, some bridges may be closed for safety reasons. The structure of the bridges is rarely in doubt, although there have been cases of bridges collapsing in strong winds. The chief concern is for the safety of the vehicles that cross the bridge, particularly high-sided lorries and trucks. Those bridges in especially high positions are most prone to closure.
When the wind reaches speeds of 65 miles an hour, the bridge closes to traffic.
A category one hurricane starts at 75 miles per hour.
The Mackinac Bridge Authority says there was a gust up to 72 miles per hour on Sunday.
It caused both a camper and a boat on a trailer to tip over on the bridge.
Typically the bridge would be closed at that wind speed, but that storm front only took a couple of minutes to go from calm winds to hurricane gusts.
“We’re expected to get some pretty bad storms this week so everybody should take their time driving across the bridge,” said Bob Sweeney from the Mackinac Bridge Authority. “If you’re driving across the bridge during a high wind event, even if it’s only 20 miles per hours, or the winds only 20 miles per hour, drive slow, drive 20 miles per hour and you’ll safely get across the bridge.”
At 35 miles per hour, the bridge authority starts escorting high profile vehicles like trucks or trailers.
At 55 miles per hour, it is closed to those high profile vehicles.
To keep an eye on the wind, the bridge authority watches weather reports online, and they have their own wind meter on the bridge.
Picture Credit : Google