Why do people drive through floodwater?

You will have seen recent pictures of a Porsche in water up to its roof. The Porsche was in a dip in the road (not a ford - as was widely and incorrectly reported). The dip in the road is beneath a railway bridge (the railway is on raised ground). Rather than raise the railway line higher, the authorities dug ground out from beneath the track. In recent months it has filled with water a couple of times. When cycling I have taken off shoes and socks and waded through - easy to do; there is a depth scale on each side of the railway track. Given the situation, and given the conspicuous and easily read depth scale, what sort of nincompoop attempts to drive a low-slung sports car through the water when an abundance of alternative roads are within a couple of miles?

Asked on 2 February 2013 by PDG, via email

Answered by Honest John
I worried about that today. There is a village named Piercebridge that regularly gets flooded on my route from the A1 cross-country to my parent's house. There are sandbags out around the pub, but happily no flood. Interestingly, I had the cruise control cut out on me briefly on the M1.The car's systems had detected slippage from standing water and automatically knocked it out of cruise. So that old advice not to use cruise in heavy rain does not apply to F30 320dEDs.
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