To hand the water to requires quite a gymnastic feat (10)
I believe the answer is:
handspring
'a gymnastic feat' is the definition.
(I've seen this before)
'to hand the water' is the wordplay.
'the water' becomes 'spring' (spring water is a kind of water**).
'hand'+'spring'='HANDSPRING'
'to requires quite' acts as a link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for handspring that I've seen before include "Somersault, cartwheel" , "Gymnast may perform this" , "turnover" , "gymnastic feat" , "Jump using hands" .)