Press Release

California Water Service Group Schedules Third Quarter 2011 Earnings Results Announcement and Teleconference

SAN JOSE, CA, Oct 13, 2011 (MARKETWIRE via COMTEX) -- California Water Service Group (NYSE: CWT) today announced that its third quarter earnings results will be released after the market-close on Wednesday, October 26, 2011, and its teleconference will be held at 11 a.m. EDT on Thursday, October 27, 2011.

All stockholders and interested investors are invited to listen to the teleconference. The 2011 third quarter conference call may be accessed by dialing 1-888-312-3055 and keying in ID# 4591937. A replay of the call will be available from 2:00 p.m. EDT on Thursday, October 27, 2011, through December 26, 2011, at 1-888-203-1112, ID# 4591937. The call, which will be hosted by President and Chief Executive Officer Peter C. Nelson and Vice President and Chief Financial Officer Martin A. Kropelnicki, will also be webcast under the investor relations tab at

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 more than 2 million people in 100 California, Washington, New Mexico, and Hawaii communities. Group's common stock trades on the New York Stock Exchange under the symbol "CWT."

1720 North First Street San Jose, CA 95112-4598

Contact: Shannon Dean (310) 257-1435

SOURCE: California Water Service Group