Leviticus 11:36
Nevertheless a spring or a cistern in which water is gathered shall be clean, but that which touches their carcass shall be unclean.
World English Bible (Public Domain)
In context
Before · Leviticus 11:34–35
34All food which may be eaten which is soaked in water shall be unclean. All drink that may be drunk in every such vessel shall be unclean. 35Everything whereupon part of their carcass falls shall be unclean; whether oven, or range for pots, it shall be broken in pieces. They are unclean, and shall be unclean to you.
36Nevertheless a spring or a cistern in which water is gathered shall be clean, but that which touches their carcass shall be unclean.