You often find this kind of road sign in South Australia.
Why do you think a road in some parts of Australia is only passable during the dry season and not recommended to be used, once it has rained?
Sure, the road might be flooded, but most 4×4 can run though it, if not too deep. Usually there are depth marker in flood areas, which indicated the water level. So there must be some other reason.
Well, it was all dry when I cycled passed it, thus I could not check it myself.
However the following road sign, which I saw soon after, may explain why it is dangerous to enter the road in the rainy season!
Can you see from what the motorists are being warned?
So better don’t leave the car, when you get stuck in water on a flooded road 