Sayyidah Maymunah (may Allah be pleased with her) narrated: The Messenger of Allah (peace and blessings be upon him) and I were both in a state of major impurity (janabah). I bathed from a large tub and some water was left over. Then the Prophet (peace and blessings be upon him) came and bathed from it. I said: O Messenger of Allah, this is water left over from my use. He (peace and blessings be upon him) said: "Water is not affected by major impurity."
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 20332