<PAGE>

                                                                EXHIBIT 10(u)(6)

                    RELIANT ENERGY, INCORPORATED SAVINGS PLAN

                (As Amended and Restated Effective April 1, 1999)

                                 Fifth Amendment

                  CenterPoint Energy, Inc., a Texas corporation (formerly
Reliant Energy, Incorporated), having reserved the right under Section 10.3 of
the Reliant Energy, Incorporated Savings Plan, as amended and restated effective
April 1, 1999, and as thereafter amended (the "Plan"), to amend the Plan, does
hereby amend the Plan, to make certain design changes and certain law changes in
accordance with the Economic Growth and Tax Relief Reconciliation Act of 2001,
effective as of the dates set forth below, as follows:

                  1.       Effective as of August 31, 2002, the Plan is hereby
amended to provide that all references to "Reliant Energy, Incorporated" are
deleted and replaced in lieu thereof with "CenterPoint Energy, Inc." and the
definition of "Company" in Article I of the Plan is hereby amended to read as
follows:

                  "1.8     COMPANY: CenterPoint Energy, Inc., a Texas
         corporation, or a successor to CenterPoint Energy, Inc., in the
         ownership of substantially all of its assets."

                  2.       Effective as of October 2, 2002, the Plan is hereby
renamed the CenterPoint Energy, Inc. Savings Plan, with all references in the
Plan amended accordingly, and the definition of "Plan" in Article I of the Plan
is hereby amended to read as follow:

                  "1.39    PLAN: The CenterPoint Energy, Inc. Savings Plan set
         forth herein, which is intended to constitute a profit-sharing plan
         under Section 401(a)(27) of the Code and an employee stock ownership
         plan under Section 4975(e)(7) of the Code, including all subsequent
         amendments hereto."

                  3.       Effective as of October 2, 2002, the Plan is hereby
amended to provide that all references in the Plan to "Reliant Energy,
Incorporated Savings Trust" are hereby deleted

<PAGE>

and replaced in lieu thereof with "CenterPoint Energy, Inc. Savings Trust" and
the definition of "Trust Agreement" in Article I of the Plan is hereby amended
to read as follows:

                  "1.68    TRUST AGREEMENT: The CenterPoint Energy, Inc. Savings
         Trust, as amended and restated effective April 1, 1999, and as it may
         hereafter be amended from time to time."

                  4.       Effective as of January 1, 2002, Section 2.15 of the
Plan is hereby amended to delete the penultimate sentence in such section.

                  5.       Effective as of January 1, 2002, the first sentence
in Section 2.16 of the Plan is hereby amended to read as follows:

         "If an application filed by an Applicant under Section 2.15 above shall
         result in a denial of the benefit applied for, either in whole or in
         part, such Applicant shall have the right, to be exercised by written
         request filed with the Committee within 60 days after receipt of notice
         of the denial of his application, to request a review of his
         application and of his entitlement to the benefit for which he applied
         by the Committee."

                  6.       Effective as of January 1, 2002, Section 2.16 of the
Plan is hereby amended to delete the penultimate sentence in such section.

                  7.       Effective as of January 1, 2002, the first sentence
of Section 4.16 of the Plan is hereby amended to read as follows:

         "Notwithstanding any other provision of the Plan, subject to the terms
         and conditions set forth in this Section, the Trustee shall be
         authorized to accept a rollover of an Eligible Rollover Distribution,
         as defined in Section 6.7(b)(i), on behalf of or from a person who is
         (or who will be entitled under Section 3.1 to become) a Participant in
         the Plan, from an Eligible Retirement Plan, as defined in Section
         6.7(b)(ii)."

                  8.       Effective as of January 1, 2002, the second paragraph
of Section 6.5 of the Plan is hereby amended to read as follows:

         "Otherwise, except to the extent that distribution of a Participant's
         Account is required prior to termination of his employment under
         Section 6.10 hereof (in the case of a Participant whose required
         beginning date occurs prior to his termination of employment) or under
         Section 10.5 hereof relating to termination of the Plan, or at the
         election of the Participant under Article VII hereof relating to
         certain

                                        2

<PAGE>

         withdrawals and loans, no distribution or withdrawal of any benefits
         under the Plan shall be permitted prior to the Participant's
         `separation from employment, death or disability' within the meaning of
         Code Section 401(k) and the regulations thereunder other than a
         distribution authorized under the Plan upon the occurrence of an event
         described in, and made in accordance with, Code Section 401(k)(10) or
         any successor provision of the Code. Notwithstanding the foregoing, if
         there is a transfer of Plan assets and liabilities relating to any
         portion of a Participant's Account under the Plan to a plan being
         maintained or created by such Participant's new employer (other than a
         rollover or elective transfer), then such Participant has not
         experienced a "severance from employment" for purposes of the Plan."

                  9.       Effective as of January 1, 2002, clause (i) of
Section 6.7(b) of the Plan is hereby amended to add the following new sentence
to the end thereof:

         "A portion of a distribution shall not fail to be an Eligible Rollover
         Distribution merely because the portion consists of after-tax
         contributions that are not includible in gross income; provided,
         however, that such after-tax portion may be transferred only to (1) an
         individual retirement account or annuity described in Code Section
         408(a) or (b) or (2) a qualified defined contribution plan described in
         Code Section 401(a) or 403(a) that agrees to separately account for
         amounts so transferred, including separately accounting for the portion
         of such distribution which is includible in gross income and the
         portion of such distribution which is not so includible."

                  10.      Effective as of January 1, 2002, clause (ii) of
Section 6.7(b) of the Plan is hereby amended in its entirety to read as follows:

                  "(ii)    Eligible Retirement Plan: An Eligible Retirement Plan
         is: (1) an individual retirement account described in Code Section
         408(a); (2) an individual retirement annuity described in Code Section
         408(b); (3) an annuity plan described in Code Section 403(a); (4) an
         annuity contract described in Code Section 403(b); (5) a qualified
         trust described in Code Section 401(a) that is exempt from taxation
         under Code Section 501(a); or (6) an eligible plan under Code Section
         457(b) that is maintained by a state, political subdivision of a state,
         or any agency or instrumentality of a state or political subdivision of
         a state and that agrees to separately account for amounts transferred
         into such plan from the Plan; that accepts the Distributee's Eligible
         Rollover Distribution. The definition of Eligible Retirement Plan shall
         also apply in the case of a distribution to a surviving spouse, or to a
         spouse or former spouse who is the alternate payee under a qualified
         domestic relation order, as defined in Code Section 414(p)."

                                        3

<PAGE>

                  11.      Effective as of January 1, 2002, Section 7.5 of the
Plan is hereby amended to add the following new sentence to the end thereof:

         "With respect to clause (i) above, the available loan balance will also
         be reduced by the amount of any prior loan that is deemed distributed
         under Code Section 72(p) and that has not been repaid (such as by a
         plan loan offset)."

                  IN WITNESS WHEREOF, CenterPoint Energy, Inc. has caused these
presents to be executed by its duly authorized officer in a number of copies,
all of which shall constitute one and the same instrument, which may be
sufficiently evidenced by any executed copy hereof, this 19th day of December,
2002, but effective as of the dates specified above.

                                     CENTERPOINT ENERGY, INC.

                                     By:  /s/ DAVID M. MCCLANAHAN
                                         ---------------------------------------
                                         David M. McClanahan
                                         President and Chief Executive Officer

ATTEST:

/s/ RUFUS S. SCOTT
---------------------------
Assistant Secretary

                                       4