Did You Know?

Monte Vista Water District's customers use on average 17 million gallons of water per day, and up to double that on a peak day.

Your Water District

The District Administrative Building in MontclairThe District Administrative Building in Montclair

1,2,3-Trichloropropane (TCP)

The State of California recently adopted a new water quality standard for 1,2,3-Trichloropropane (TCP), a manmade chemical historically used by the agricultural industry as a soil fumigant.

Upon receiving notification of the newly proposed water quality standard, MVWD adjusted operations to ensure compliance with the standard prior to it going into effect. MVWD also began planning financial options for building new treatment plants to ensure compliance with the new water quality standard during periods of reduced imported water supply availability.

Water quality is our number one priority at MVWD, and we take pride in providing the highest quality water service at the best value for our customers. We encourage you to learn more about the quality of our water supply by reviewing MVWD's most recent Annual Water Quality Report, available for download at www.report.mvwd.org.

Frequently Asked Questions

  • What is TCP?
    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 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.
  • What is Monte Vista Water District doing about TCP?
    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.
  • How is TCP removed from the water?
    TCP can effectively be removed using granular-activated (GAC) technology. GAC is also recognized by the State of Californiais also recognized as the "best available technology" to remove TCP and is the exact technology that the District will be implementing to remove TCP.
  • Where can I learn more about Monte Vista Water District's water quality?
    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.


We want your input. Monte Vista Water District values feedback from all members of the community as we strive to make the best decisions for our customers. Fill out our online feedback form.

Additional Information