What is the purpose of the barrels filled with water on the American freeways?
You must out west. I just heard about this from my Aunt, who just made the same trip. In the desert they put barrels of water every so many miles so that if your radiator boils over in the heat, you only have to walk so far to get water to fill it. But if you are talking about just barrels with no water in them, they are to absorb the force of an impact like others have said. They are supposed to absorb most of your kinetic energy before you get to the concrete bridge abutment.
