There are metal towers you can climb along the road for cases like this. The down side is having to wait half a day on one of the towers to find your car washed away.
Connecting the Gulf of Burnёf with the island of Noirmoutier, Passage du Gois is not only unique but extremely dangerous too. Twice every day, when the high tide rises, the 2.58-mile long road disappears 13 ft under water. So people can use this road only two times a day for a few hours.
The road is not supervised so it is up to the drivers to determine if the road is safe enough to travel. There are special panels on each side of the road that indicate if the road’s safe to drive on or not. Unfortunately, there are still numerous drivers who get trapped on the road every year because of the rising tides. Either the drivers aren’t aware of the danger or the traffic is heavy on the road and they get trapped in the middle as the water rises. The good news is there are tall rescue towers that exist all along the road. So if a person gets caught on the road when the water elevates, they can just climb the tower and wait for help to come. The downside is their car will be washed away.