I found out the worst way possible...
TDI DSG
The depth was surveyed to be about 1.5 Ft max , i was expecting 3/4th of the tire to be submerged, and cruise through.
The shaft which developed ahead of the bumper was seen over the hood once in a while , at the deepest point the DSG decided to engage the 2nd gear ,revs went from about 2k to a 1000, bam.... and the engine stalled.
we had to push the car out , bucketed out the water , and damage assessment started ,
The first effort was made about 2 hours after , the engine did not crank , just the CLICK sound from some relay some where , under hood , on inspection I found water in the GLOW PLUG cavities , used an air compressor to blow dry the cavities , NO LUCK
I opened the Air filter awaiting a horror story but to my surprise it was all good , clean and dry
A fellow decided to help us and towed us for about 50Odd clicks (The power steering seemed to be working as long as the tires were moving, i always taught its PURELY engine based)
Some where during the Tow I decided to crank , and we had POWER , i let the engine heat up , and bang , we had juice ,
Damage assessment ,
The water that entered the passenger compartment blew the AIRBAG module (Just ahead,below of the gear stick , ) Also blew the Communication BUS , right next to the AIRBAG Module
and blew the Amp , under the Passenger seat
Retrospect : -
Max Water wading depth - Half the Tire
While water wading - Use Triptronic and stick to the First gear+ High RPM