If you've been to Gatlinburg, Tennessee, you have probably grabbed a bite or a beverage along the Cliff Branch River, normally a serene, beautiful experience.
So, judging by my totally unscientific research, it appears that the vehicle drove into the ditch, and didn't just "get flooded" on Ambassador Caffery.
As flood waters slowly recede and people take stock of everything they've lost, please don't tell them "it's just stuff". Because it's a whole lot more than that.