How can I fix a Ford Puma '97 Drivers Footwell Leak?

Hi all,

I have a P reg 1997 Ford Puma, about 4 months or so after i got it we had 2 days with heavy rain and when i went to get in the car the drivers footwell was like a sponge full of water.
The rest of the car is bone dry and this only happens when it rains.
I have checked under the dash and around the pedals. As soon the carpet starts going up the sides and behind the pedals it gets dry again. There is nothing dripping from above and the pedals themselves are dry too. I've got a feeling it is soaking up from almost underneath in the top right corner of the footwell (if looking at it from above). It isn't from water splashing up from the road while travelling as it happens when the car is parked.
I have looked below the windscreen under the bonnet, there was a bit of leaf debris but not much and it was all dry too so nothing obvious there. I couldn't see any other obvious holes or missing seals compared to the passenger side of the car, altho im no expert on what should be where on a Ford.

Any ideas or suggestions would be greatly appreciated!

Thanks!