I had this happen, but with my fender. I was on the highway and a plow coming on the other side of the divider flung snow and ICE CHUNKS over the barrier... I wasn't too close, I was in my lane. I contacted my local police department and they deferred to the State Police / DoT.

I couldn't get a hold of someone as I kept getting deferred in circles so I just gave up and ate the cost because it was a small fix.