Musnad Abu Ya'la al-Mawsili 159:9

Abu Khaythama narrated to us, Sufyan narrated to us, from Abu al-Zinad, from al-A'raj, from Abu Hurayrah, who said: The Messenger of Allah (may Allah bless him and grant him peace) said: "The surplus of water shall not be withheld, so that the pasture may be withheld by it."