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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                    FORM 8-K


                                 CURRENT REPORT

                         PURSUANT TO SECTION 13 OR 15(d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934

       Date of Report (Date of earliest event reported): December 22, 2005

                         California Water Service Group
             (Exact name of registrant as specified in its charter)


           Delaware                     1-13883                 77-0448994
           --------                     -------                 ----------
(State or other jurisdiction      (Commission File No.)       (IRS Employer 
      of incorporation)                                   Identification Number)


   1720 North First Street San Jose, California                   95112
   --------------------------------------------                   -----
(Address of principal executive offices)                        (Zip Code)

                                 (408) 367-8200
              (Registrant's telephone number, including area code)

                                       N/A
          (Former name or former address, if changed since last report)

Check  the  appropriate  box  below  if the  Form  8-K  filing  is  intended  to
simultaneously  satisfy the filing obligation of the registrant under any of the
following provisions (see General Instruction A.2. below):

[_]  Written  communications  pursuant to Rule 425 under the  Securities Act (17
     CFR 230.425)

[_]  Soliciting  material pursuant to Rule 14a-12 under the Exchange Act (17 CFR
     240.14a-12)

[_]  Pre-commencement   communications  pursuant  to  Rule  14d-2(b)  under  the
     Exchange Act (17 CFR 240.14d-2(b))

[_]  Pre-commencement   communications  pursuant  to  Rule  13e-4(c)  under  the
     Exchange Act (17 CFR 240.13e-4(c))

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Item 1.01 Entry into a Material Definitive Agreement

     As previously  reported,  Richard D. Nye, former Chief Financial Officer of
the Company,  submitted his resignation from the Company  effective  October 27,
2005 and the Company and Mr. Nye have since then been  negotiating  the terms of
separation arrangements. The Company and Mr. Nye have now agreed to a Separation
Agreement and Release dated as of December 15, 2005, which provides, among other
terms, as follows:

     o    payment to Mr.  Nye,  previously  made on October 28,  2005,  of final
          salary through October 27, 2005, plus six weeks' unused vacation,  and
          one weeks' salary as termination wages;

     o    the amount of $137,500 minus applicable tax withholding, equivalent to
          six months'  salary,  payable upon Mr. Nye's request made by March 31,
          2006;

     o    continuing  entitlement to any benefits accrued as of October 27, 2005
          under the registrant's pension plan, supplemental executive retirement
          plan,  and deferred  compensation  plan. Mr. Nye was hired on March 1,
          2003,  and as such,  has not  vested in the  pension  or  supplemental
          executive  retirement  plan under the vesting terms of the  respective
          plans.  Benefits accrued Mr. Nye under the deferred  compensation plan
          were solely contributed to the plan by Mr. Nye;

     o    payment of Mr. Nye's current medical insurance  premiums for 12 months
          in the aggregate amount of $6,795, less tax withholding;

     o    allowing  Mr. Nye to purchase a  company-owned,  a 2003 Avalon  Toyota
          automobile, at a price of $17,000, which was more than trade-in value;
          and

     o    the  agreement  also  contains  a  release  of  any  liability  of the
          registrant by Mr. Nye.


The  agreement  was  revocable for seven days from the date of its execution and
became  irrevocable  on December 22, 2005. The above summary of the agreement is
qualified in its entirety by reference to the terms of the  agreement,  which is
attached as Exhibit 10 to this report and incorporated herein by reference.


Item 9.01.  Financial Statements and Exhibits

(c)      Exhibits:

     The exhibit  list called for by this item is  incorporated  by reference to
the Exhibit Index filed as part of this report.

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                                    SIGNATURE

     Pursuant to the  requirements  of the Securities  Exchange Act of 1934, the
registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned, hereunto duly authorized.


Dated:   December 22, 2005


                                       CALIFORNIA WATER SERVICE GROUP


                                       By: /s/ John S. Tootle
                                          --------------------------------------
                                                     John S. Tootle
                                                 Acting Vice President, 
                                          Chief Financial Officer and Treasurer
                                                (Duly Authorized Officer)


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                                  Exhibit Index
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----------------------- -------------------------------------------------------------------------------------
       Exhibit
        Number                                              Description
----------------------- -------------------------------------------------------------------------------------
                      
          10            Separation Agreement and Release between California Water Service Group and Richard
                        D. Nye dated as of December 15, 2005
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