CHIEF EXECUTIVE OFFICER CERTIFICATION
Published on November 12, 2002
Exhibit 99.1
CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002
In connection with the Quarterly Report of California Water Service Group
("Company") on Form 10-Q for the period ending September 30, 2002 as filed with
the Securities and Exchange Commission on the date hereof (the "Report"), I,
Peter C. Nelson, President and Chief Executive Officer of the Company, certify,
pursuant to 18 U.S.C. Section. 1350, as adopted pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002, that:
(1) The Report fully complies with the requirements of Section 13(a) or 15(d)
of the Securities Exchange Act of 1934; and
(2) The information contained in the Report fairly presents, in all material
respects, the financial condition and results of operations of the Company
/s/ Peter C. Nelson
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Peter C. Nelson
President and Chief Executive Officer
November 7, 2002