I have only been involved in one disaster in my life. And that was small scale. Two trains came around a bend at normal speed and hit head-on. Evidently, one of them was not supposed to be there. They hit directly under a busy highway overpass that eventually melted into an unusable mess.

I was a paramedic at the time. There was a massive traffic jam. Not of civilian vehicles, but of emergency vehicles. My ambulance and lots more were deadlocked amongst other ambulances, firetrucks, police cars, utility vehicles, etc. It didn't take long for all of us to abandon the roadways and start driving across the fields to get to the scene. I was quite impressed with the speed and size of the response. Unfortunately, there was nobody to save. The people in the front of the trains were long gone, and the ones in the back simply stepped off unharmed after the movement finally stopped (these were long freight trains, not passenger trains, and no hazardous materials thankfully). The front of the trains were piled up into a multi-story teepee looking mess that burned and melted the overpass.

This was a Friday evening. The train people cleaned a hole through the mess and the local road crews built a brand new road through that hole bypassing the melted overpass. This was all constructed and in use by Monday mornings rush hour. That was quite an impressive response from these hard working guys. This was not a dirt road bypass. It was a fully paved and lined four lane bypass.