Thousands of San Luis Obispo County residents were recently warned to boil or purify their drinking water after tests detected a strain of coliform bacteria in the water supply. The bacteria, which was found in the water distribution system of Zone 3 of the San Miguelito Water Co., is an early indication of a potential E. coli contamination. … This is the first time coliform bacteria contamination at the Lopez distribution system has triggered a boil water notice, the county Public Works Department said in a Thursday news release. Here’s what to know about the potentially dangerous water contaminant. 

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