Black-colored tap water on Mayo Clinic's Saint Marys Campus spurred the hospital to use bottled water throughout the facility, according to an article on the Post Bulletin website.
Visitors and staff reported that water in toilet bowls turned black also.
Patients, visitors and staff were told to refrain from drinking the water or using ice from the ice machines.
The situation was restricted to Saint Marys campus and the surrounding homes and businesses on Second Street Southeast are not being affected.