Isolated community (9)
(Other definitions for backwater that I've seen before include "Place where no development happens" , "in the sticks" , "place of inactivity" , "Stagnant part of a river" , "Isolated place" .)
'isolated community' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for enclave that I've seen before include "Area enclosed within a foreign territory" , "Part of country surrounded by another" , "Piece of territory within another country" , "Small territory owned by one state but lying within another" , "Isolated territory enclosed by valence" .)