Finding a water leak 2013 Altima

Check the drain holes in the bottom of the rear doors. They may be blocked with dirt and debris. HTH. -Jim

Just checked the drain holes on the doors and they are clear

Check the trunk ... it may be getting in through the rubber weather seal

The water usually comes in from a seam at the firewall that wasn't sealed properly at the factory. You don't see it on the front carpet because it goes under the styrofoam that is on the floor board.

any pics of location of seam that is leaking?

here is the location of my leak

Im now getting water in on the passenger side floor also. This is way too common for Nissan not to cover. I called the local Nissan and they guy told me it would be 1200 just to check for leak.