the carpets in my passat 1.9 tdi estate are soaking wet?

I had this fault with my own 1.9tdi and it turned out to be the pollen filter seal

Michael
May 2011

The drainage points in the tray the battery and servo sit in get blocked. Feel under the tray under the battery and pull out the rubber gromit. You will be amazed at how much water is in the tray. Leave the gromit out.

Murray
March 2011

I seem to recall that this question has been posted before.
If its the near side front passenger footwell then it might be an incorrectly installed pollen filter or housing.
Or
if car has a sunroof, blocked drain tubes
or
leaking heater matrix

Maurice
February 2011