Exhibit 23.1




CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM


The Board of Directors and Stockholders
California Water Service Group


We consent to  incorporation  by reference in the  registration  statements (No.
333-103721)  on Form S-3 and (No.  333-60810)  on Form S-8 of  California  Water
Service  Group of our reports  dated  February  22,  2005,  with  respect to the
consolidated  balance sheets of California  Water Service Group and subsidiaries
as of December 31, 2004 and 2003,  and the related  consolidated  statements  of
income,  common stockholders' equity and comprehensive income and cash flows for
each of the years in the three-year period ended December 31, 2004, management's
assessment of the effectiveness of internal control over financial  reporting as
of December 31, 2004, and the  effectiveness  of internal control over financial
reporting as of December 31, 2004.


/s/ KPMG LLP


Mountain View, California
February 22, 2005