Abu Dawud
Purification (Kitab Al-Taharah)
Book Number: 001 / Hadith Number: 66
Narated By Abu Sa'id al-Khudri : The people asked the Messenger of Allah (pbuh): Can we perform ablution out of the well of Buda'ah, which is a well into which menstrual clothes, dead dogs and stinking things were thrown? He replied: Water is pure and is not defiled by anything.