Clues I arranged for Watergate! (6)
I believe the answer is:
sluice
'watergate' is the definition.
(I've seen this before)
'clues i arranged' is the wordplay.
'arranged' is an anagram indicator (letters rearranged).
'clues'+'i'='cluesi'
'cluesi' is an anagram of 'SLUICE'.
'for' acts as a link.
(Other definitions for sluice that I've seen before include "Sliding gate to control water in stream" , "Water flow control gate" , "Water-controlling gate" , "Floodgate" , "Drench copiously" .)