Our Water Supply

Reliable Local Water

Cal Domestic is a wholesale water supplier for its shareholders, Suburban Water Systems and the Cities of La Habra and Brea. Shareholders rely mostly on Cal Domestic to meet their local water demands, and may combine those supplies with water from their own local groundwater sources or other wholesale suppliers such as the Metropolitan Water District of Southern California.

Cal Domestic operates seven active groundwater wells that supply water from the Main San Gabriel Basin. After water is pumped from the groundwater basin, it is conveyed through a series of treatment facilities to ensure it meets or exceeds all water quality regulations and standards. Following treatment and quality assurance, the water is delivered to shareholders through approximately 30 miles of pipeline beginning in Los Angeles County and ending in north Orange County, crossing the Cities of El Monte, Industry, Whittier, La Habra, La Habra Heights, and Brea. Each year, Cal Domestic supplies shareholders with approximately 20,000 acre-feet of water. That’s more than six billion gallons!

Installing the 48-inch M-Line, the main delivery pipeline that provides water for all Company shareholders.
Installing the 48-inch M-Line, the main delivery pipeline that provides water for all Company shareholders.

Water sales have remained remarkably stable over the past quarter century. Cal Domestic has been able to meet shareholder demands even during droughts, and to increase deliveries to meet spikes in demand.

Water Quality

Delivering Quality Water Is Our Top Priority

Two field technicians in the field testing water.

Our state certified water quality experts test water throughout the water delivery pipelines.

Extensive Sampling and Testing for Quality Assurance

Cal Domestic operates and maintains advanced water treatment systems and conducts extensive sampling and testing for quality assurance. Cal Domestic annually schedules regular collection of over 2,000 samples for a number of constituents as required by state and federal regulations to ensure that high-quality water is consistently delivered to shareholders.

Proactive Management for Optimum Water Operations

With virtually the entire water system rebuilt or replaced in recent years, Cal Domestic focuses its operations on proactive management of water distribution and treatment facilities to lower long-term costs and improve supply reliability.

Highly Skilled, Certified Operators

The State of California mandates various levels of training, experience, and certification for operators of differing water facilities. Cal Domestic’s system is rated at the highest level of complexity, requiring Grade 5 certification for the treatment system and Grade 4 certification for the distribution system. Che Venegas, the Director of Water Operations, is certified as a Grade 5 operator in both treatment and distribution—one of only about 70 people in California with this dual top-level certification.

Cal Domestic’s Team of Certified Operators

PositionT = TreatmentD = Distribution
Senior Water Utility WorkerT4D5
Senior Water Utility WorkerT4D5
Water Utility Worker IIT2D3
Water Utility Worker IT2D2

Proactive Treatment Facility Management

Cal Domestic operates and maintains three primary treatment facilities to ensure that the water supplied to shareholders meets or exceeds all water quality regulations and standards. The Company’s Air Stripper Treatment Facility, Ion Exchange Treatment Facility, and Ultraviolet (UV) Light Treatment Facility each utilize state-of-the-art technologies to treat groundwater supplies to meet safe drinking water standards. All these essential facilities require frequent scheduled maintenance activities to ensure effective operation. Learn more about Cal Domestic’s Proactive Management of Facilities for Cost-Savings and Quality.

Annual Consumer Confidence Reports

California regulations require Consumer Confidence Reports to be produced and distributed to shareholders annually. Cal Domestic also collects samples and conducts tests for many constituents, as required by both state and federal regulations. The Consumer Confidence Reports show the results of Cal Domestic’s annual sample monitoring and other quality assurance information. These reports are available through the links below. Shareholders typically combine water quality information provided by Cal Domestic with water quality data from their own local wells or other sources to produce their required reports to residential, commercial, and industrial consumers.

Water Supply Reliability and Value

With water rights originating in the late 1800’s, Cal Domestic provides shareholders with a reliable water supply by securing affordable regional water resources in the Main San Gabriel Basin. The south Puente Hills stretches from the San Gabriel River to Brea.  Cal Domestic’s shareholders enjoy a unique alternative to importing expensive Northern California water, especially during droughts or other water supply emergencies that shut down local wells. Learn more about Cal Domestic’s performance improving and cost-saving measures.
Technician working on a large water pipe system.


Cal Domestic’s shareholders are subject to new water conservation mandates under AB-1668 and SB-606 that require reductions in the amount of water consumed by average households, as well as outdoor water use reductions. These laws were signed into law in 2018 and are referred to as “Water Conservation as a Way of Life.” By 2022, the new laws will require that households limit their daily water consumption to 55 gallons per person. By 2030, daily residential use will be limited to 50 gallons per person. Cal Domestic is actively working to help devise ways to meet these state requirements in collaboration with others from around the state. Keep up-to-date with the development of requirements for Water Conservation as a Way of Life(this will take you to a new website).

Like other water suppliers, Cal Domestic is insisting on protecting local decision-making about the best conservation practices for each community. As water use reduction measures are implemented and water utility revenues decline, the state must also protect investments needed to maintain infrastructure integrity, emergency preparedness, and water quality.

Supporting our Shareholders

Cal Domestic has made substantial contributions to conservation programs such as a $35,000 payment each to the City of La Habra’s Civic Center, the City of Brea’s Community Center and schools, golf courses  and other facilities served by Suburban Water Systems.

These low-water-use landscaping projects are examples of shareholder conservation projects that were financially supported by Cal Domestic: (left) City of Brea Community Center, (middle) La Habra Civic Center, and (right) Whittier Greenway trail, which is supported by Suburban Water Systems.

Links to Water Conservation Information