When we drive a car in out day to day life, we find lot of obstacles in roads. Water covered areas or flooded areas are one of the main obstacles we may find on a road. The decision we take to Drive trough it or not is a very critical decision. Because if we don't know the road well it is dangerous to drive through since we have no idea about distance of the water area, depth of water, cracks or holes in the road etc.
You may attempt to drive through a water area if you are familiar with that road and if you know it is safe to through. Typical procedure of driving through a water area is driving in moderate speed (10-20 Km/h) in gear position one without slowing down the engine until you cross the area. You can't stop the car in middle of water because if you stop, water may go in to the engine through the silencer and engine will stop eventually.