Around here, you're encouraged to call 911 for anything that might require a public safety person to show up. That includes debris in the road, reporting accidents even if just a fender-bender, etc.

The reason is that there IS no other phone number in most areas around here where you can call and be guaranteed of getting anyone. Even the dispatch is routed around between townships; no station is really manned all the time, the state's budgets have been cut so many times in the last 10 years that basically almost everyone who is in uniform is either on patrol or doing paperwork or appearing in court or something all the time; there are usually only a handful of dispatchers and they have to route police, fire, ambulance and maybe other services as well (animal control, whatever).

The police come to the schools here and advise kids to call 911 whenever they're really scared, including if someone in their house won't wake up. They do tell the kids not to screw around, because once 911 is dialled, they're required by law to send an officer to the scene.

I've called 911 when I witnessed accidents, but also when there was dangerous debris in the road, since crud in the road can easily cause multiple car pileups (especially on an expressway where people are already driving at least 20 MPH faster than they should, and pretty much everyone follows at least twice as close as they should).