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                                                                       Exhibit 5
                                                               September 8, 1997





Northwest Pipeline Corporation
295 Chipeta Way
Salt Lake City, Utah 84108

Gentlemen:

         You have requested me, as General Counsel of The Williams Companies,
Inc., to render my opinion regarding certain matters in connection with the
preparation and filing of a registration statement by Northwest Pipeline
Corporation (the "Company") on Form S-3 (the "Registration Statement") under
the Securities Act of 1933, as amended, with respect to $350,000,000 aggregate
initial offering price of debt securities ("Securities").  The Securities are
to be issued from time to time as senior indebtedness of the Company under an
indenture between the Company and Chase Manhattan Bank, as trustee (the
"Indenture").  The form of the Indenture and the Securities are filed as
exhibits to the Registration Statement.

         I am familiar with the Certificate of Incorporation and the By-laws,
each as amended to date, of the Company and have examined the originals, or
copies certified or otherwise identified to my satisfaction, of corporate
records of the Company, statutes and other instruments and documents as the
basis for the opinion expressed herein.  In addition, I am, or someone under my
supervision is, familiar with the forms of the Indenture and the Securities.

         Based upon the foregoing, and having regard for such legal
considerations as I have deemed relevant, I am of the opinion that, when the
Securities have been duly authorized by the Board of Directors of the Company,
the Indenture has been duly executed and delivered and the Securities have been
duly issued in accordance with the provisions of the Indenture and duly paid
for by the purchasers thereof, all required corporate action will have been
taken with respect to the issuance and sale of the Securities, and the
Securities will have been validly issued and will constitute valid and binding
obligations of the Company enforceable in accordance with their terms, except
as enforceability may be
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limited by bankruptcy, insolvency, reorganization or other laws relative to or
affecting generally the enforcement of creditor's rights and by principles of
equity.

         I hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to the undersigned appearing under
the caption "Legal Matters" in the related Prospectus.
                                        
                                        Very truly yours,



                                        William G. von Glahn