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                                                                       EXHIBIT 5

                     [Letterhead of Baker & Botts, L.L.P.]

                                                                  August 8, 1997



Houston Industries Incorporated
Houston Industries Plaza
1111 Louisiana
Houston, Texas  77002

Ladies and Gentlemen:

     We have acted as counsel for Houston Industries Incorporated (formerly
known as Houston Lighting & Power Company), a Texas corporation (the "Company"),
in connection with the Registration Statement on Form S-3 (the "Registration
Statement") filed by the Company with the Securities and Exchange Commission
(the "Commission") under the Securities Act of 1933, as amended (the "Securities
Act"), relating to the issuance from time to time of up to 944,974 shares
(the "Shares") of common stock, without par value, of the Company (and
associated rights to purchase Series A Preference Stock, without par value, of
the Company (the "Rights")) upon conversion of the 6-1/4% Convertible Junior
Subordinated Debentures (the "Debentures") of NorAm Energy Corp. (formerly known
as HI Merger, Inc.), a Delaware corporation ("New NorAm"). The Debentures are
governed by an Indenture dated as of June 15, 1996, as amended and supplemented
(the "Indenture"), between New NorAm as successor in interest to NorAm Energy
Corp., a Delaware corporation ("Old NorAm"), and The Bank of New York, as
trustee.

     In our capacity as your counsel in the connection referred to above, we
have examined the Restated Articles of Incorporation and Amended and Restated
Bylaws of the Company, each as amended to date, the Agreement and Plan of Merger
dated as of August 11, 1996, as amended, by and among Houston Industries
Incorporated, a Texas corporation ("Old HII"), the Company (formerly a wholly
owned subsidiary of Old HII), New NorAm and Old NorAm, the Indenture, and the
Amended and Restated Rights Agreement dated as of August 6, 1997 between the
Company and Texas Commerce Bank National Association (the "Rights Agreement")
and have examined originals, or copies certified or otherwise identified, of
corporate records of the Company, including minute books of the Company as
furnished to us by the Company, certificates of public officials and of
representatives of the Company, statutes and other instruments or documents, as
a basis for the opinions hereinafter expressed.  In giving such opinions, we
have relied upon certificates of officers of the Company with respect to the
accuracy of the material factual matters contained in such certificates.  In
making our examination, we have assumed that all signatures on all documents
examined by us are genuine, that all documents submitted to us as originals are
accurate and complete, that all documents submitted to us as copies are true and
correct copies of the originals thereof and that all information submitted to us
was accurate and complete.
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Houston Industries Incorporated            -2-                    August 8, 1997


     On the basis of the foregoing, and subject to the assumptions, limitations
and qualifications set forth herein, we are of the opinion that:
 
          1.  The Company is a corporation duly organized and validly existing
     in good standing under the laws of the State of Texas.

          2.  The Shares, when duly issued upon conversion of the Debentures in
     accordance with the terms thereof and the terms and provisions of the
     Indenture, will be validly issued, fully paid and non-assessable.

          3.  The issuance of the Rights associated with the Shares has been
     duly authorized by all requisite corporate action on the part of the
     Company and, upon issuance from time to time in connection with the
     issuance of the associated Shares as provided above and in accordance with
     the terms of the Rights Agreement, the Rights associated with such Shares
     will be validly issued.

          The opinion set forth in paragraph 3 above is limited to the valid
issuance of the Rights under the Texas Business Corporation Act.  In this
connection, we do not express any opinion herein on any other aspect of the
Rights, the effect of any equitable principles or fiduciary considerations
relating to the adoption of the Rights Agreement or the issuance of the Rights,
the enforceability of any particular provisions of the Rights Agreement, or the
provisions of the Rights Agreement which discriminate or create unequal voting
power among shareholders.

          The opinions set forth above are limited in all respects to matters of
Texas law as in effect on the date hereof.  At your request, this opinion is
being furnished to you for filing as Exhibit 5 to the Registration Statement.
Additionally, we hereby consent to the reference to our Firm under the caption
"Legal Opinions" in the Registration Statement.  In giving such consent, we do
not thereby concede that we are within the category of persons whose consent is
required under Section 7 of the Securities Act or the rules and regulations of
the Commission promulgated thereunder.

                                    Very truly yours,

                                    BAKER & BOTTS, L.L.P.



MSS/TST