If a tractor trailer is dropping small rocks onto the freeway, should you call 911?

Q. While driving on the eastbound 91 Freeway in Anaheim Hills, a refrigerated tractor trailer was leaking water from the back door – it was like a waterfall, very heavy. I was debating whether to call 911; it was not really an emergency. Then a few miles ahead there was an empty dump truck, which did not have a net on. My car was getting pelted with small rocks, and dust was still coming out of the truck’s back. Should I have called 911 for that? It wasn’t really a em