I need Arizona, the salt we use is from a mine in central Utah.
While road salts are bad for metal vehicles, abrasives like sand or cinders aren't without consequences either. They end up in washes and streams, altering stream hydrology.
Regarding the bridges, many of the older bridges were constructed with uncoated rebar, and road salts got into the rebar, causing deck failures. Also got in to the superstructure causing damage. Modern bridges are built with epoxy coated rebar and super structures made with different steel alloys and designs to better withstand road salts.
