A station didn't secure the filler cap and a rainstorm put quite a bit of water in the tank. The first couple motorists to fill got more water than gas.
Locally I go to one of two stations to fill. Both have a great deal of traffic, so run through a lot of gas. And if I see the fuel truck at the station, I come back later, after there's been enough time for the crap to settle out.
Allegedly, they're supposed to have in-line filters to filter out dirt and water. Obviously, in the case of water, it can be easily overwhelmed.
Definitely want to run some Heet through the tank, and probably for the next couple of tanks, just to be sure all the water is removed. Water is not kind to sensors, pumps, or fuel injectors.