Officials in Baltimore, Maryland, are trying to flush out the city's water system after E. coli was discovered in drinking water over the weekend.
The city believes the contamination is contained to the Sandtown-Winchester and Harlem Park neighborhoods, which are predominantly Black and low-income areas.
Contamination was detected when Baltimore's Department of Public Work sampled drinking water at the Baltimore Police Department's Western District Station, and the Engine 8 Fire Station.
According to the Centers for Disease Control, some kinds of E. coli can cause diarrhea, urinary tract infections, pneumonia and other illnesses.
A boil advisory is in effect for the affected areas.
However, some residents said they didn't know about the advisory until it was too late.
"So I found out after I got to work and after we had all brushed our teeth and drank water and the dogs drank water," Baltimore County resident Lorena Ahern said on Tuesday.
The city is also handing out water at several locations. However, there is a limit of three gallons per household.