I have a 2014 S60 and keep finding water in the footwell after it rains. I removed all flooring from the car and found the water is coming from the driver side when it rains, during the car sitting overnight.
After the rain, I dried the floors, closed the car and poured water from the hose over the top of the car for 20 minutes and no water entered the car. This is a mystery I am trying to solve.

How can a car only get water inside from rain and not from a hose?

 

Could be from the door or the drain in front of the windshield underneath the cowl. I know the p2s (pre-09) had an issue with the cowl drain near the CEM so maybe you got something loose there. The drain goes to the wheel well so its possible that theres something broken on there making it go to the driver side floor.

 

Thanks for the reply. I tried to cover all problems and found the water is coming from the door seal and leaking into the car. The car is parked on a level ground, fills under the door sill and fills into the car. I will try to attach a video to show the water entry.