Do you know that it will take between 450 and 500 years for a PET bottle to degrade?
The simplest way to recycle PET water bottles is to refill them with water rather than buy another one!
Given that more than 25% of all bottled water comes out of a tap anyway, doesn't that make sense? And if you're worried about fluoride and chlorine, use a filter or boil the water.
At least you'll know where the water has come from