California Water Service, also called California Water, is a holding company, which engages to provide water utility and other related services in California, Washington, New Mexico, and Hawaii through its wholly-owned subsidiaries. The company is involved in the production, purchase, storage, treatment, testing, distribution and sale of water for domestic, industrial, public, and irrigation uses, as well as for fire protection. Read More It also provides non-regulated water-related services under agreements with municipalities and other private companies. The company was founded in 1926 and is headquartered in San Jose, CA. The listed name for CWT is California Water Service.