The City of Sonoma water system recently violated a drinking water standard. Although this is not an emergency, all customers have a right under State law to know what happened, and what the City did to correct this situation.
The Water Department routinely monitors for drinking water contaminants. Twelve water samples were taken to test for the presence of coliform bacteria during January 2010. Two of our samples showed the presence of total coliform bacteria. The standard is that no more than one sample per month/5.0 percent of samples may do so. This is not an emergency. If it had been, customers would have been notified immediately. Total coliform bacteria are generally not harmful themselves. Coliforms are bacteria which are naturally present in the environment and are used as an indicator that other; potentially-harmful, bacteria may be present. Coliforms were found in more samples than allowed, and any time coliform bacteria is detected in any sample, the City is required to conduct follow-up testing to see if other bacteria of greater concern, such as fecal coliform or E. coli, are present. None of these bacteria were found in subsequent testing, and further testing shows that this problem has been resolved, as repeat samples came back negative.
The City published the required notice regarding this violation in the local newspaper on February 9, 2010. On March 8, 2010, the City was subsequently notified that mailed notice to each water customer was required. As such, a comprehensive notice will be included in each customer’s next Water Utility Bill as required by the County Health Department.
The City of Sonoma Water Department strives to deliver safe, high quality water, and delivers approximately 673 million gallons to 4,350 water customers annually. The Water Department’s staff is trained and certified on the policies and procedures of taking water samples. The Water Department is investigating the cause of the positive bacteria sample. For more information, please contactSteve MacCarthy, Water Operations Supervisor, at 707-933-2231 or #1 The Plaza, Sonoma, CA 95476.
