Pleasant Grove has issued a boil advisory after finding E. coli in three samples collected during a monthly test of the city’s culinary water system.

The samples came from the area encompassing 300 North between 300 East and 400 East in Pleasant Grove, according to FOX 13.

City officials have determined the E. coli contamination is an isolated incident, impacting nine service connections in that area. The cause has yet to be determined.

Preliminary results from tests taken Saturday in the neighborhood near 300 North and 300 East came back Sunday negative for coliform, the city tweeted. More tests were expected Sunday.

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