Treatment and Testing
Our Water Quality Department manages processes to proactively collect water samples, regularly test quality, and effectively treat water in order to meet or surpass requirements. The department leads our efforts to leverage advanced technology and collaborate with federal, state, and regulatory agencies. To help preserve water quality during droughts, wildfires, and other events, we monitor environmental conditions and adjust operations as needed to maintain safety.
We manage extensive monitoring programs and over 800 different treatment processes to meet over 250 water quality standards, including requirements from the federal Safe Drinking Water Act (SDWA) and applicable state regulations. To accomplish this at each entry point to the distribution system, we employ programs that are specifically designed to improve water quality, such as our award-winning groundwater treatment projects.
In California, we collect more than 70,000 water samples from our water systems and conduct more than 400,000 water quality tests every year. We analyze the majority of water samples from our California service areas at our in-house laboratory in San Jose. For the remaining samples, we outsource testing only to state certified contract laboratories that align with our licensing and quality thresholds. Our lab has achieved Environmental Laboratory Accreditation Program (ELAP) certification for 23 years by passing annual site audits performed by the State of California or a third-party assessor. We also adhere to The NELAC Institute (TNI) Laboratory Accreditation Standards, adopted by ELAP, to meet more rigorous laboratory operational requirements.
We use our Laboratory Information Management System (LIMS) to manage data collection, quality control, reporting, and regulatory compliance programs in California and Washington. We update the LIMS regularly to expand functionality, scope of use, and capabilities of the application. We plan to incorporate the LIMS in our remaining states of operation.
In addition to meeting regulations in California related to drinking water, we also maintain safety certifications for any direct additives or products that may come into contact with drinking water. These products or chemicals are certified for meeting the specifications of NSF International/American National Standard Institute (NSF/ANSI). If there are any issues related to water quality and safety, we have systems in place designed to notify customers quickly and proactively.
In advance of regulations, we proactively conduct additional testing, maintain transparency about our performance, and support research on emerging contaminants. Every five years, we also participate in the Unregulated Contaminant Monitoring Rule (UCMR) program to collect occurrence data on emerging contaminants. We support legislation to prohibit products that may impact water quality, thereby protecting the water supply before contamination can occur.
Our process to evaluate methods to treat emerging contaminants aligns with our standard approach for treatment and testing. We consider best available technologies (BAT), cost-effectiveness, and the existence of any co-contaminants that must also be removed. Other site-specific factors include lot size, operational considerations, and discharge and waste disposal options.
While there are no state or federal Maximum Contaminant Levels (MCLs) yet for per- and polyfluoroalkyl substances (PFAS) compounds, we continue to closely monitor the regulatory process at state and federal levels, follow recommendations from regulators, review existing and new treatment methods, and develop a response strategy to help prepare us to meet anticipated Maximum Contaminant Levels. Where detections of PFAS in our California systems have exceeded the response levels (RLs) advised by experts, we seek to act quickly by either removing the source from service or installing treatment for PFAS. We use granular activated carbon treatment, reverse osmosis, and ion-exchange technologies to remove contaminants where needed.
We also treat affected water supplies for chromium-6, which experts suggest is harmful to human health and for which the California State Water Resources Control Board is developing a new Maximum Contaminant Level. To treat chromium-6, we use strong base anion exchange or reduction, coagulation, oxidation, and filtration treatment methods. We began treating water supplies for chromium-6 shortly after the safe drinking water standard was set in 2014, and we have continued to meet the threshold for affected active water sources as regulations have evolved.
Preventing lead contamination that may result from corrosion of lead-bearing components in distribution infrastructure or household plumbing is another primary focus of our efforts to protect the health and safety of our customers. We monitor water quality and test for lead in drinking water as required by law; maintain and upgrade our systems to support compliance with health and safety codes mandating use of lead-free materials in water system replacements, repairs, and new installations; frequently test for corrosivity of the water and add corrective measures when necessary to prevent lead from home plumbing fixtures from affecting water quality; and carefully plan and conduct water quality testing before using any new source of water. We also provide educational resources for customers to learn about lead contamination and how they can reduce potential exposure to lead in drinking water.
While there are no known lead service lines within Cal Water systems, the updated Lead and Copper Rule from the Environmental Protection Agency includes expanded requirements to complete service line inventories on both the water utility’s and the customer’s side of the water meter to identify lead in drinking water. As part of our compliance strategy for this updated rule, we are currently conducting an inventory to identify potential lead service lines on the customer side of the water meter.
To help address the emerging risks of microplastics, we are identifying future opportunities to monitor microplastics at certain facilities in alignment with guidance from the California State Water Resources Control Board’s Division of Drinking Water.
Through our cross-connection control program, we manage actual or potential connections between potable water supply and non-potable matter that can contaminate water supplies in the event of backflow, where hydraulic conditions cause the direction of water flow to reverse. Our Water Quality team oversees this program to help protect our distribution system from any activities on customers’ properties. At-risk customers are required to install, test, and maintain proper backflow prevention measures designed to align with regulations and avoid potential liability. Our experts confirm annual testing of backflow prevention assemblies, assess all water connections, and administer new commercial and residential assemblies.
Our Water Quality Department includes experts with a large variety of certifications and qualifications related to cross-connection control, laboratory analysis, and treatment. Because the responsibility for water quality does not lie with the Water Quality Department alone, Operations Department staff receive water quality training on a variety of topics, including SDWA regulations, sample collection, analytics equipment use, field analysis, operation of specific treatment equipment, and additional technical information. Attendees are required to prove comprehension of sample collection by taking a written exam after training. We encourage employees in all roles to learn more about water quality by engaging in relevant training, certification processes, and conferences.
We submit hundreds of monthly performance reports to the California State Water Resources Control Board’s Division of Drinking Water. The Division of Drinking Water also audits existing facilities, including wells, tanks, and pipelines, and provides permits for new operations.
To help residents and businesses across our subsidiaries learn about their local water supply, we prepare annual Consumer Confidence Reports. Available on our subsidiary websites, these water quality reports provide information on the water supply, sustainability, testing, standards, and other topics. Customers may also request a copy by contacting their local Customer Center.