Press Release

California Water Service Group Named a Top Workplace in Bay Area

SAN JOSE, CA--(Marketwire - Jun 21, 2012) - Based on survey responses from employees of its subsidiary California Water Service Company, California Water Service Group (Cal Water) (NYSE: CWT) has been named one of the Top Workplaces in the Bay Area in 2012 by the Bay Area News Group.

Cal Water is a regulated water utility with 334 employees in the Bay Area in its San Jose headquarters and its Bayshore, Bear Gulch, Los Altos, and Livermore Districts. The company serves 109,200 customer connections in its Bay Area operations.

"Our employees dedicate themselves to ensuring the health and safety of our customers and providing the best possible service," said Cal Water's Chairman & CEO Pete Nelson. "I am honored to be part of this organization."

The rankings in the Top Workplaces are based on survey information collected by Workplace Dynamics, an independent company specializing in employee engagement and retention. Rankings were composite scores calculated purely on the basis of employee responses about company leadership, compensation and training, diversity/inclusion, career development, family-friendly flexibility, and values and ethics. Private companies and non-profits as well as publicly held businesses were included in the analysis.

Mac Tully, president and publisher of Bay Area News Group Newspapers, said, "Despite the challenges of the economy, the Bay Area continues to set the standard for progressive companies such as California Water Service Group, which provides positive, enriching work experiences for its employees."

California Water Service Group is the parent company of California Water Service Company, Washington Water Service Company, New Mexico Water Service Company, Hawaii Water Service Company, Inc., CWS Utility Services, and HWS Utility Services, LLC. Together these companies employ 1,132 people who provide regulated and non-regulated water service to approximately 2 million people in more than 100 California, Washington, New Mexico, and Hawaii communities. The company's common stock trades on the New York Stock Exchange under the symbol "CWT."

1720 North First St.
San Jose, CA 95112

Contact:
Shannon Dean
(310) 257-1435