Call the Backcountry Information Office for GSMNP at (865) 436-1297. The hours are 9-12 noon EST, daily. Be patient, number is often busy or you get a message to leave your call back info. The office is staffed with volunteers, so be patient. They can give you the latest info on water sources, shelters and what you need to do. You need a backcountry permit which is free and can be obtained at the ranger stations or the visitor centers. Thirty days before you enter the park you can request a reservation for your planned shelters stays.
Happy Trails!
Steamer