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 of Form 10-Q for the Quarter
Ended June 30, 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: August 13, 2003                             /s/ Peter C. Nelson
                                                  ------------------------------
                                                  PETER C. NELSON
                                                  Chief Executive Officer
                                                  California Water Service Group



Date: August 13, 2003                             /s/  Richard D. Nye
                                                  ------------------------------
                                                  RICHARD D. NYE
                                                  Chief Financial Officer
                                                  California Water Service Group

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