“The Messenger of Allah ﷺ ruled concerning the stream of Mahzur that the higher ground took precedence over the lower, so the higher ground should be irrigated until the water reached the ankles, then it should be released to those who were lower.
قَضَى رَسُولُ اللَّهِ ﷺ فِي سَيْلِ مَهْزُورٍ الأَعْلَى فَوْقَ الأَسْفَلِ يَسْقِي الأَعْلَى إِلَى الْكَعْبَيْنِ ثُمَّ يُرْسِلُ إِلَى مَنْ هُوَ أَسْفَلُ مِنْهُ