Around these parts, lots of emphasis on when not to drive through water thanks to flash floods (we have what's known as the Stupid Motorist Law ... basically, you pay for the rescue if you try to cross water when it's a dumb thing to do).

From the NOAA website: "a depth of two feet will float your car." Moving water compounds things.

Here's a webpage you might find useful: A Selected Few 4 Wheel Driving Tips.