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                                                                   EXHIBIT 4.15 

                               SECOND AMENDMENT
                                      TO
                        MINNEGASCO DIVISION EMPLOYEES'
                            RETIREMENT SAVINGS PLAN


          Minnegasco, a division of NorAm Energy Corp., a Delaware corporation
(the "Company"), hereby amends the Minnegasco Division Employees' Retirement
Savings Plan, effective as of November 1, 1996, as follows:

1.   Section 7.4.1 of the Plan is hereby amended to read as follows:

     "7.4.1  Voting.  The Trustee shall be authorized to vote the shares of
     Stock held in the Trust pursuant to this Section. As soon as practicable
     after notice of any shareholders' meeting given to shareholders, the
     Administrator or Administrative Delegate shall prepare and deliver to each
     individual who has a Stock Account, or a directed investment in a pooled
     investment trust which holds Stock, a notice and a form of proxy to direct
     the Trustee as to how the Trustee shall vote at that meeting, or any
     adjournment of that meeting, that number of full shares of Stock allocated
     to that Participant's Account as of the record date of the meeting of the
     Company's shareholders.  The notice shall instruct each Participant who has
     Stock in an Account to return the proxy to the Trustee, or to such other
     entity (including the Administrator) as the Administrator may select. If an
     independent entity other than the Trustee is directed to collect and tally
     the proxies, the entity shall certify the results to the Trustee and shall
     also deliver all proxies to the Trustee.  The Trustee is not required to
     independently verify the results which have been certified to it.

          The Trustee shall vote all shares of Stock held by it (including
     fractional shares) for which it has received instructions in accordance
     with those instructions. The Trustee shall vote all shares of Stock held by
     it in suspense accounts and shares of allocated Stock for which it has not
     received instructions in the same proportion as it votes the shares for
     which it receives timely instructions under this Plan."

2.   Section 7.4 of the Plan is hereby amended to add the following Subsection
7.4.3 to the end thereof:

          "7.4.3  Merger Transaction.  By Agreement and Plan of Merger, dated as
     of August 11, 1996, as amended, by and among NorAm Energy Corp. ("NorAm"),
     Houston Industries Incorporated ("HI"), Houston Lighting & Power Company
     ("HL&P"), and HI Merger, Inc. (the "Merger Agreement"), NorAm has agreed to
     merge into HI Merger, Inc. and become a wholly owned subsidiary of Houston
     (the corporation to be formed by the merger of HI and HL&P) (the
     "Transaction"). The Merger Agreement provides that each record holder of
     shares of Stock outstanding immediately prior to the effective time of the
     Transaction shall be entitled to elect 

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     to receive in respect of each such share either cash consideration or
     shares of HI common stock. The Trustee will, in accordance with the
     procedures established by the Employee Benefits Administrative Committee of
     NorAm (the "Committee") for that purpose, request each Participant and
     Beneficiary who has Stock allocated to his Accounts as of the date
     established by the Committee, to instruct the Trustee as to the percentage
     of his interest in the Stock fund for which he wishes to receive cash and
     the percentage for which he wishes to receive HI common stock. The Trustee
     will make elections as to shares of Stock for which instructions are not
     timely received in the same proportion as the elections it makes for shares
     for which it receives timely instructions under this Plan. Elections shall
     be subject to adjustment as provided in the Merger Agreement.

          Cash consideration received in the Transaction by a Participant or
     Beneficiary will be invested as soon as administratively practicable in the
     investment funds (including the Stock fund) in which the Participant has
     elected to invest contributions to the Plan on the date the cash
     consideration is received by the Trustee or, in the case of a Participant
     or Beneficiary for whom contributions are not being made on such date, in
     the investment funds in which the Participant's or Beneficiary's account
     balances are invested on such date.  The cash consideration will be
     allocated among the investment funds in the same proportion as
     contributions or account balances, as the case may be, are allocated.

          The Committee may adopt such other rules and procedures with respect
     to the administration of the Plan as are necessary or appropriate, in its
     sole discretion, as a consequence of the pending Transaction,
     notwithstanding any provision of this Plan to the contrary. Such rules and
     procedures shall be applied on a uniform and nondiscriminatory basis."

          Executed at Houston, Texas, this 17th of  December, 1996.

                                    MINNEGASCO, a Division of
                                      NorAm Energy Corp.


                                    By /s/ RICK L. SPURLOCK
                                       --------------------------  
                                       Rick L. Spurlock, Senior Vice President,
                                       Human Resources, NorAm Energy Corp.

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