Water on rear floorboard

SOURCE: there is a water leak

I am the original owner of camry xle 1998 with wet floors. In 2000 I had drivers side door seal leaking at welt. Removed old door seal and new weather strip on drivers side installed. The door panel was never wet, but wet at bottom of door where there are drain holes...slowly leaking under carpet.
In 2001 later water again. Coming from overflowing A/C evaporator-drain plugged/ tank full of debris. Removed evaporator, cleaned + drain cleaned.
In 2003, driver door seal against window rotted. Removed door panel and found leak at window belt molding at the mirror joint inside + out. Lots of mold under carpet needed to replace! Made a fuss at dealers for reacurring problem and they replaced the carpet for free.

SOURCE: there is a water leak

This would be your Heater core. They are very cheap to purchase but not so easy to put in since you have to drop the underneath of the dashboard out and aslo have to remove the lines from inside the engine compartmnet. The water goes from the radiator through the heater core to produce the heat for your heater. You should check your radiator or overflow bottle and if the water level is low then this is definetly your problem. This is the most logical, however there could but unlikely be a leak from your windshield. The heator core is located exactly where you say the water is coming from. After reading more does this happen more times other then when it is raining?

SOURCE: 2002 Toyota RAV4 passenger side floor Water

Hi, we also have a 2002 Toyota Rav4 and developed a leak in the front driver's side of the car. After much research, we discovered that the drain wells from our sun/moon roof were clogged. If you have one of these, I suggest that you open the sun roof and look carefully. You will notice some tiny little holes in front and in the rear of the sun/moon roof tracks. Over time, these become clogged with dust and debris. You need to find a long, sturdy piece of thin wire and run it down the holes. To test if you have properly unclogged these, take a small amount of water and pour it down the holes. You should see water coming out of the drain wells under the car around the rear of the front tires. Hope this helps.

SOURCE: water leak on fwd and back passenger side after every rain storm

pull your carpet up near the leak area and look for muddy body seams. it is possible one of the factory body seams are leaking- possibly in the cowl(under wipers) area, especially if it leaks when the car is sitting. there will be dirt/mud around the seams that are leaking. also you can check door seals by running the car on HIGH DEFROST with all doors and windows closed. spray around with a 50/50 soapy water solution. obviously bubbles will form around your leak.

SOURCE: I have water leaking on the right rear floor passenger side

Sounds to me like your issue is with condensation from your air conditioner. The condensation isn't properly draining, probably from a damaged or clogged drain hose.