It was narrated from 'Amr bin Shu`aib, from his father, from his grandfather, that :
the Messenger of Allah (ﷺ) ruled concerning the stream of Mahzur that the water should be retained until it reached the ankles, then released. (IT)
English reference (IT): Vol. 3, Book 16, Hadith 2482 (IT)
Arabic reference (IT): Book 16, Hadith 2576 (IT)