We encourage you to review our most recent Annual Water Quality Report (PDF). For additional questions or requests for further information, call 909-624-0035, ext. 185.
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1,2,3-Trichloropropane (TCP) is a chemical that was an unnecessary ingredient in agricultural soil fumigants applied to farm fields from the 1950s to the 1980s. After being applied to the ground over many years, TCP has migrated down into our groundwater and has been detected in several District wells. The State Water Resources Control Board, Division of Drinking Water (DDW) says that, while TCP levels in our water do not pose a health emergency and there is no need to use an alternative (e.g. bottled) water supply, some people who drink water containing TCP over many years may have an increased risk of cancer, based on studies of laboratory animals.
The District is committed to providing high quality drinking water that meets or exceeds all state and federal water quality standards at all times. As such, the District has stopped pumping certain wells where TCP has been detected and is in the process of designing and constructing treatment facilities to remove TCP from the water before it is made available to our customers.
TCP can effectively be removed using granular-activated carbon (GAC) technology. GAC is also recognized by the State of California as the "best available technology" to remove TCP and is the exact technology that the District will be implementing to remove TCP.