Evacuation of shower during day time... (8)
I believe the answer is:
drainage
'evacuation' is the definition.
(drainage is a kind of evacuation)
'shower during day time' is the wordplay.
'shower' becomes 'rain' ('rain shower' can be a synonym of 'shower').
'during' indicates putting letters inside.
'day' becomes 'd'.
'time' becomes 'age' (age is a kind of time).
'd'+'age'='dage'
'rain' put inside 'dage' is 'DRAINAGE'.
'of' is the link.
(Other definitions for drainage that I've seen before include "Disposal of waste water" , "Means of removing water" , "Water removal system" , "Removal of surplus water" , "System to manage waste water" .)