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                                                                 Exhibit 10.12.4

                      SUPPLEMENTAL PARTICIPATION AGREEMENT

                  A Participation Agreement made and entered into this 30th day
of December, 2003, between The Crystal Water Company of Danielson (hereinafter
referred to as the Participating Employer"), Connecticut Water Company
(hereinafter referred to as the `Employer') and Riggs Bank N.A. (hereinafter
referred to as the "Trustees').

                  WHEREAS, the Participating Employer desires to reward its
employees for faithful service, to establish a bond between employer and
employee, to provide an incentive for efficient and conscientious work, to
provide a fund for retirement, disability, or death, and to retain high-calibre
fellow employees; and

                  WHEREAS, there exists a 401(k) Profit Sharing Plan entered
into on the 30th day of December, 2003, namely the SAVINGS PLAN OF THE
CONNECTICUT WATER COMPANY, called the "Plan," between the Employer and the
Trustees (a copy being attached hereto as Exhibit "A" and made a part hereof by
reference); and

                  WHEREAS, the Plan provides that any other Participating
Employer may, with the consent of the Employer, adopt the Plan and participate
therein by a properly executed document evidencing said intent of said
Participating Employer;

                  NOW, THEREFORE, the Participating Employer hereby becomes a
party to the Plan, effective the 1st day of January, 2004, and the Employer and
the Trustees hereby consent to such adoption and participation upon the
following terms:

                  (1)      Wherever a right or obligation is imposed upon the
                  Employer by the terms of the Plan, the same shall extend to
                  the Participating Employer as the "Employer" under the Plan
                  and shall be separate and distinct from that imposed upon the
                  Employer. It is the intention of the parties that the
                  Participating Employer shall be a party to the Plan and
                  treated in all respects as the Employer thereunder, with its
                  employees to be considered as the Employees or Participants,
                  as the case may be, thereunder. However, the participation of
                  the Participating Employer in the Plan shall in no way
                  diminish, augment, modify, or in any way affect the rights and
                  duties of the Employer, its Employees, or Participants, under
                  the Plan.

                  (2)      The Trustees hereby agree to receive and allocate
                  contributions made to the Plan by the Employer and by the
                  Participating Employer, as well as to do and perform all acts
                  that are necessary to keep records and accounts of all funds
                  held for Participants who are Employees of the respective
                  employers.

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                                                                 Exhibit 10.12.4

                  (3)      The execution of this Agreement by this Participating
                  Employer shall be construed as the adoption of the Plan in
                  every respect as if said Plan had this date been executed
                  between the Participating Employer and the Trustees, except as
                  otherwise expressly provided herein or in any amendment that
                  may subsequently be adopted hereto.

                  (4)      All actions required by the Plan and Trust to be
                  taken by the Employer shall be effective with respect to the
                  Participating Employer if taken by the Employer and pursuant
                  to the Plan, the Participating Employer hereby irrevocably
                  designates the Employer as its agent for such purposes.

         IN WITNESS WHEREOF, the Participating Employer, the Employer and the
Trustees have caused this Supplemental Participation Agreement to be executed in
their respective names on the day and date first above written.

                                  Unionville Water Company

                                  By: /s/  Maureen P. Westbrook