Aging infrastructure contributed to an E. coli contamination of the city of Baltimore’s water system in early September, officials said.
A confluence of events in several parts of the water system reduced chlorine levels, which led to three positive tests for E. coli, a Department of Public Works official told The Washington Post.
City officials also detailed their findings during a City Council hearing Thursday.
The contamination led to a boil water advisory for a wide swath of the city and into Baltimore County, which is served by the city system.
No illnesses were linked to the contaminated water, a city spokeswoman said Friday.