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 Annual  Report on Form 10-K for the year ended
December  31, 2003 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: February 25, 2004               /s/ Peter C. Nelson
                                               PETER C. NELSON
                                               Chief Executive Officer
                                               California Water Service Group

         Date: February 25, 2004               By: /s/  Richard D. Nye
                                               RICHARD D. NYE
                                               Chief Financial Officer
                                               California Water Service Group