Baltimore City officials are lifting the boil tap water notice on the city’s west side after water samples were confirmed as negative for E. coli bacteria on Friday morning. The Maryland Department of the Environment worked in partnership with the city on the measure.

“We have tested not just that [boil advisory] area but across the whole system and there have been no positives,” Baltimore City Mayor Brandon Scott said.

City leaders recommended that all households within the original advisory area still flush their water systems using cold water for at least 15 minutes. The city expects to offer a 25% discount on the water bill of residents affected by the boil water notice.

Baltimore officials first discovered E. coli bacteria in water samples collected in the Harlem Park and Sandtown neighborhoods last Friday.

The city began remediation measures earlier this week such as adding more chlorine to the water treatment plants which flow into the residential pipes or flushing out fire hydrants with potentially contaminated water. The cause of the contamination is still under investigation.