Exhibit 32


                                  CERTIFICATION
                       PURSUANT TO 18 U.S.C. SECTION 1350,
                       AS ADOPTED PURSUANT TO SECTION 906
                        OF THE SARBANES-OXLEY ACT OF 2002

Pursuant  to  Section  906  of  the  Sarbanes-Oxley  Act of  2002,  each  of the
undersigned  certifies  that this  Quarterly  Report on Form 10-Q for the period
ended  September 30, 2005 fully complies with the  requirements of Section 13(a)
or 15(d),  as applicable,  of the  Securities  Exchange Act of 1934 and that the
information  contained in this Report fairly presents, in all material respects,
the financial  condition  and results of operations of California  Water Service
Group.




    Date: November 9, 2005         /s/ Peter C. Nelson
                                   ---------------------------------------
                                   PETER C. NELSON
                                   Chief Executive Officer
                                   California Water Service Group



    Date: November 9, 2005         /s/  John S. Tootle
                                   ---------------------------------------
                                   JOHN S. TOOTLE
                                   Acting Chief Financial Officer and Treasurer
                                   California Water Service Group