She stitched up drainpipes (5)
I believe the answer is:
sewer
'she stitched up' is the definition.
(someone sewing or stitching up)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for sewer that I've seen before include "Tailor" , "Embroiderer; soil pipe" , "It drains" , "dressmaker?" , "Disposal outlet" .)