Water Quality
PWS # 04-00008, Butte County
P.O. Box 1495
Chico, CA 95927-1495
On the left are several links to past Consumer Confidence Reports that show the results of water quality testing. These reports show that Gran Mutual has excellent water quality. These reports are known as "CCR's" and are mailed to the members each year.
There can be a problem with water quality if there is contamination from some source.. The indicator that the Dept. of Health uses is a measure for contaminations is a test of bacteria. Experience has shown one type of bacteria is known to be associated with disease causing organisms. This is coliform bacteria. When there is a possitive test result for coliform, the water company will follow the "total coliform rule." This rule gives the best treatment with disinfectants based on the continued testing. The treatment is under the control of the Butte County Health Department.
Most water systems chlorinate in order to protect users from any pathogens. By maintaining a small chlorine residual in the water, the water is safe to drink. When the source is deep wells, which is Gran Mutual's water source, chlorine disinfection is not required.
If there is a positive test result, the system has to be checked again and in more detail. If there is another positive, then the problem has to be found and fixed. Usually, the system is flushed and disinfected with chlorine
The most common cause for contamination is backflow from water that has been in contact with bacteria. This can be from irrigation, pools, or many other ways. Because of this, the water system is required to have a backflow education program for the members and periodic surveys to look for backflow sources. They are also required to maintain positive pressures above 35 p.s.i. at all times.
Flushing dead end lines and hydrants, plus tank cleaning are all regular maintenance tasks that must be done to avoid bacteria development inside the water system.
2009 Consumer Confidence Report
2008 Consumer Confidence Report
Field Testing Site Results
New Well Water Testing Results