Exhibit 99.1

1720 North First Street San Jose, CA 95112-4598		March 31, 2008 For Immediate Release

Contact:		Martin A. Kropelnicki (408) 367-8200
		(analysts)
		Shannon Dean (310) 257-1435 (media)

CALIFORNIA WATER SERVICE GROUP ANNOUNCES
SELECTION OF DELOITTE & TOUCHE LLP
AS INDEPENDENT REGISTERED PUBLIC ACCOUNTANTS

     SAN JOSE, CA — California Water Service Group (NYSE : CWT) today announced the selection of Deloitte & Touche LLP (Deloitte) as the Company’s independent registered public accounting firm, subject to their customary client acceptance procedures.

     In February of this year, the Company’s audit committee decided, in accordance with good corporate governance practices, to undertake a thorough assessment of audit firms that serve regulated companies. After conducting an extensive evaluation process, the audit committee selected Deloitte based on the firm’s audit approach, reputation in the utility space, and local market presence.

     The selection of Deloitte was not the result of any disagreements between the company and the current independent registered public accounting firm, KPMG L.L.P., on any matters of accounting principles or practices, financial statement disclosure, or auditing scope or procedures.

     “California Water Service Group has had a very long and satisfying audit relationship with KPMG and we want to thank the firm for its service,” said Chief Financial Officer Martin Kropelnicki.

     “We look forward to working with Deloitte over the next few months as they transition into their new role with us,” he said.

     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 provide regulated and non-regulated water service to approximately 2 million people in more than 100 California, Washington, New Mexico and Hawaii communities. Group’s common stock trades on the New York Stock Exchange under the symbol “CWT.”

     This news release contains forward-looking statements within the meaning established by the Private Securities Litigation Reform Act of 1995 (“Act”). The forward-looking statements are intended to qualify under provisions of the federal securities laws for “safe harbor” treatment established by the Act. Forward-looking statements are based on currently available information, expectations, estimates, assumptions and projections, and management’s judgment about the Company, the water utility industry and general economic conditions. Such words as expects, intends, plans, believes, estimates, assumes, anticipates, projects, predicts, forecasts or variations of such words or similar expressions are intended to identify forward-looking statements. The forward-looking statements are not guarantees of future performance. They are subject to uncertainty and changes in circumstances. Actual results may vary materially from what is contained in a forward-looking statement. Factors that may cause a result different than expected or anticipated include but are not limited to: governmental and regulatory commissions’ decisions, including decisions on proper disposition of property; changes in regulatory commissions’ policies and procedures; the timeliness of regulatory commissions’ actions concerning rate relief; new legislation; changes in accounting valuations and estimates; the ability to satisfy requirements related to the Sarbanes-Oxley Act and other regulations on internal controls; electric power interruptions; increases in suppliers’ prices and the availability of supplies including water and power; fluctuations in interest rates; changes in environmental compliance and water quality requirements; acquisitions and our ability to successfully integrate acquired companies; the ability to successfully implement business plans; changes in customer water use patterns; the impact of weather on water sales and operating results; access to sufficient capital on satisfactory terms; civil disturbances or terrorist threats or acts, or apprehension about the possible future occurrences of acts of this type; the involvement of the United States in war or other hostilities; restrictive covenants in or changes to the credit ratings on our current or future debt that could increase our financing costs or affect our ability to borrow, make payments on debt or pay dividends; and, other risks and unforeseen events. When considering forward-looking statements, you should keep in mind the cautionary statements included in this paragraph. The Company assumes no obligation to provide public updates of forward-looking statements.

     Additional information is available online at www.calwatergroup.com.

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