Job security for the public servants.

We used to have the same problem with a state highway in central CA. Every winter it would disappear under 'bout 10 ft of water then mud for a distance of 'bout two miles. And every winter dummies would drive around the barricades and signs. Then get stuck, requiring highway workers, highway cops, fire guys, swift water rescue guys, and helicopters respond to save their waterlogged butts. And they would get upset that their vehicles (now ruined, but they wouldn't believe that) got left there 'til the water went down and the mud removed by a fleet of front loaders and dump truck. Then we would have a tow respond to remove the hulk, and the owners would get the bill for that. Which of course they would not pay, so the tow company had to eat the bill. Sadly, the state couldn't bill them for all of the rescue folks...