Press Release

California Water Service Ranks Highest in the West in J.D. Power Residential Water Customer Satisfaction Study

SAN JOSE, CA--(Marketwired - May 18, 2016) - California Water Service (Cal Water), the largest subsidiary of California Water Service Group (NYSE: CWT), has been ranked highest in overall customer satisfaction among water utilities in the western United States, according to J.D. Power's 2016 Water Utility Residential Customer Satisfaction Study(SM). The utility also achieved the highest score in the region for communications.

The results, announced by J.D. Power today, were based on responses in March 2016 from residential customers who had had experiences with their utility within the past six months. The Overall Water Utility Satisfaction Index measures key performance indicators in six areas: delivery, price, billing and payment, conservation, communications, and customer service.

"We are committed to providing our customers with quality, service, and value," said Martin A. Kropelnicki, Cal Water President and CEO. "We are humbled by our customers' feedback and remain dedicated to fulfilling this promise through each member of our customer service, operations, water quality, engineering, information technology, communications, and other support teams."

This is the first year J.D. Power has conducted a customer satisfaction study for water utilities. The study ranked U.S. water utilities serving a population of at least 400,000 residents by analyzing more than 28,000 online customer interviews. Utilities were categorized into the Midwest, Northeast, South, and West geographic regions.

About Cal Water
Cal Water serves about 2 million people through 480,300 service connections in California. The company has provided water service in the state since 1926. Additional information may be obtained online at www.calwater.com

About J.D. Power
Headquartered in Costa Mesa, Calif., J.D. Power is a global marketing information services company providing performance improvement, social media, and customer satisfaction insights and solutions. The company's quality and satisfaction measurements are based on responses from millions of consumers annually. For more information on car reviews and ratings, car insurance, health insurance, cell phone ratings, and more, please visit jdpower.com. J.D. Power is a business unit of McGraw Hill Financial.

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