California Water Service Group is a holding company that operates regulated public utilities and non-regulated water services across multiple western U.S. states, serving approximately two million people through seven operating subsidiaries. The company's core business involves the production, purchase, storage, treatment, and distribution of water for domestic, industrial, public, and irrigation uses, with regulated operations dominating its revenue—particularly its California subsidiary, which serves the largest portion of customers. Beyond regulated utility services, the company generates revenue from non-regulated activities including system leasing, meter reading, billing, and antenna site leases; it also develops infrastructure to meet water quality and environmental compliance standards, funded through capital investment programs and litigation settlements.