Useful thing bringing up branch stuck in a well (7)
I believe the answer is:
amenity
'useful thing' is the definition.
'up branch stuck in a well' is the wordplay.
'up' is a reversal indicator (in down clue: letters go upwards).
'branch' becomes 'tine'.
'stuck in' means one lot of letters goes inside another.
'well' becomes 'my' (I've seen this in other clues**).
'tine' in reverse letter order is 'enit'.
'a'+'my'='amy'
'enit' inserted inside 'amy' is 'AMENITY'.
'bringing' is the link.
(Other definitions for amenity that I've seen before include "Building's useful feature" , "Pleasing feature (of a place or building)" , "Facility making life easy or pleasant - any time" , "asset to the community" , "Convenience - any time (anag)" .)