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                                                                Exhibit 10.6.1

                                 AMENDMENT NO. 1
                                       TO
               NORTHEAST GENERATION COMPANY - NORTHEAST GENERATION
                                SERVICES COMPANY

                       MANAGEMENT AND OPERATION AGREEMENT


THIS AMENDMENT NO. 1 ("Amendment") to the MANAGEMENT AND OPERATION AGREEMENT
("Agreement") is made and entered into as of the 1st day of March, 2000, by and
between NORTHEAST GENERATION COMPANY, a Connecticut corporation with its
principal place of business in Berlin, Connecticut ("NGC"), and NORTHEAST
GENERATION SERVICES COMPANY, a Connecticut corporation with its principal place
of business in Rocky Hill, Connecticut ("NGS"). NGC and NGS shall be referred to
individually as the "Party" and collectively as the "Parties".

         WHEREAS, NGC and NGS entered into the Agreement as of February 1, 2000;

         WHEREAS, the United States Securities and Exchange Commission ("SEC")
has reserved jurisdiction under the Public Utility Holding Company Act of 1935,
as amended ("Act"), over the pricing provisions of the Agreement because such
pricing provisions are not fully cost-based; and,

         WHEREAS, the Parties agree that until and unless the SEC authorizes the
pricing provisions in the Agreement that do not comply with the cost provisions
under the Act, in accordance with the intent of Section 2.2 of the Agreement,
they will continue with the Agreement amended to be in accordance with the
cost-based provisions of the Act, as set forth more fully below.

         NOW, THEREFORE, in consideration of the premises and the mutual
agreements herein , it is agreed as follows:


         1.       Effective on the date of execution of this Amendment, Sections
                  4.1 to 4.3 of the Agreement and Exhibit 6 to Agreement shall
                  be suspended and replaced by the following:

                  "4.1A INTERIM PAYMENT PROVISIONS. Until such time as the SEC
                  approves or authorizes the pricing provisions contained in
                  Sections 4.1 to 4.3 of the Agreement and Exhibit 6 to the
                  Agreement, NGC shall pay NGS for the Services NGS provides
                  under Section 3 of this Agreement as described in this
                  paragraph. NGC shall pay NGS's actual total costs of providing
                  such services, including applicable overheads and indirect
                  costs, and reasonable compensation for necessary capital as
                  permitted by Rule 91 of the SEC under the Act as determined

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                  in accordance with Northeast Utilities System accounting and
                  cost allocation procedures, and with the methodologies used in
                  service agreements between Northeast Utilities Service Company
                  and various Northeast Utilities subsidiaries as approved by
                  the SEC."

         2.       RESTORATION OF INITIAL PRICING PROVISIONS. Upon SEC approval
                  or authorization for the pricing provisions contained in
                  Sections 4.1 to 4.3 of the Agreement and Exhibit 6 to the
                  Agreement, such provisions shall be immediately reinstated for
                  the period from and after the date of SEC approval or
                  authorization and the provisions of Section 1 of this
                  Agreement shall no longer be in force and effect.

         3.       EFFECT OF AMENDMENT ON AGREEMENT. The Agreement, as
                  specifically amended by this Amendment, is and shall continue
                  to be in full force and effect and is hereby in all respects
                  ratified and confirmed. The execution, delivery and
                  effectiveness of this Amendment shall not, except as expressly
                  provided herein, operate as a waiver of any right, power or
                  remedy of any party thereunder, nor constitute a waiver of any
                  provision of the Agreement.

         IN WITNESS WHEREOF THE PARTIES HAVE EXECUTED THIS AMENDMENT AS OF THE
DAY AND YEAR FIRST ABOVE WRITTEN.


NORTHEAST GENERATION COMPANY


BY: /s/ David R. McHale
   -------------------------------------
NAME:  David R. McHale
TITLE: Vice President and Treasurer


NORTHEAST GENERATION SERVICES COMPANY


BY: /s/ William J. Nadeau
   -------------------------------------
NAME:  William J. Nadeau
TITLE: Vice President and
       Chief Operating Officer


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