It is narrated from Hazrat Abu Saeed Khudri (may Allah be pleased with him) that once someone asked, "O Messenger of Allah! Can we perform ablution with the water of the well of Buda'ah?" In fact, dirty clothes of women, other foul things, and the flesh of dogs were thrown into the well. The Prophet (peace be upon him) said, "Water is pure; nothing can make it impure."