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                                                                      EXHIBIT 24


                         NORTHWEST PIPELINE CORPORATION

                                POWER OF ATTORNEY

         KNOW ALL MEN BY THESE PRESENTS that each of the undersigned
individuals, in their capacity as a director or officer, or both, as hereinafter
set forth below their signature, of NORTHWEST PIPELINE CORPORATION, a Delaware
corporation ("NWP"), does hereby constitute and appoint NICK A. BACILE AND
JEFFREY R. VALENTINE their true and lawful attorneys and each of them (with full
power to act without the other) their true and lawful attorneys for them and in
their name and in their capacity as a director or officer, or both, of NWP, as
hereinafter set forth below their signature, to sign NWP's Annual Report to the
Securities and Exchange Commission on Form 10-K for the fiscal year ended
December 31, 2001, and any and all amendments thereto or all instruments
necessary or incidental in connection therewith; and

         THAT the undersigned NWP does hereby constitute and appoint NICK A.
BACILE AND JEFFREY R. VALENTINE its true and lawful attorneys and each of them
(with full power to act without the other) its true and lawful attorney for it
and in its name and on its behalf to sign said Form 10-K and any and all
amendments thereto and any and all instruments necessary or incidental in
connection therewith.

         Each of said attorneys shall have full power of substitution and
resubstitution, and said attorneys or any of them or any substitute appointed by
any of them hereunder shall have full power and authority to do and perform in
the name and on behalf of each of the undersigned, in any and all capacities,
every act whatsoever requisite or necessary to be done in the premises, as fully
to all intents and purposes as each of the undersigned might or could do in
person, the undersigned hereby ratifying and approving the acts of said
attorneys or any of them or of any such substitute pursuant hereto.

         IN WITNESS WHEREOF, the undersigned have executed this instrument, all
as of the 18th day of February, 2002.


 /s/ J. Douglas Whisenant                            /s/ Nick A. Bacile
-------------------------------                 -------------------------------
     J. Douglas Whisenant                                Nick A. Bacile
    President, Chief Executive                       Vice President and
       Officer, and Director                      Chief Financial Officer
  (Principal Executive Officer)                 (Principal Financial Officer)


                            /s/ Jeffrey R. Valentine
                          ----------------------------
                                Jeffrey R. Valentine
                                    Controller
                         (Principal Accounting Officer)

   /s/ Keith E. Bailey                              /s/ Robert L. Sluder
-------------------------------                 -------------------------------
       Keith E. Bailey                                  Robert L. Sluder
         Director                                          Director



                                        NORTHWEST PIPELINE CORPORATION



                                                By /s/ Nick A. Bacile
                                                   ----------------------------
                                                       Nick A. Bacile
                                                      Vice President and
                                                   Chief Financial Officer

ATTEST:



    /s/ Suzanne H. Costin
-------------------------------
        Suzanne H. Costin
            Secretary


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                         NORTHWEST PIPELINE CORPORATION


         I, the undersigned, Suzanne H. Costin, Secretary of NORTHWEST PIPELINE
CORPORATION, a Delaware company (hereinafter called the "Company"), do hereby
certify that pursuant to Section 141(f) of the General Corporation Law of
Delaware, the Board of Directors of this Corporation unanimously consented, as
of February 18, 2002, to the following:

                  RESOLVED that the Chairman of the Board, the President or any
         Vice President of the Company be, and each of them hereby is,
         authorized and empowered to execute a Power of Attorney for use in
         connection with the execution and filing, for and on behalf of the
         Company, under the Securities Exchange Act of 1934, of the Company's
         Annual Report on Form 10-K for the fiscal year ended December 31, 2001.

         I further certify that the foregoing resolution has not been modified,
revoked or rescinded and is in full force and effect.

         IN WITNESS WHEROF, I have hereunto set my hand and affixed the
corporate seal of NORTHWEST PIPELINE CORPORATION this 18th day of February,
2002.


                                                /s/ Suzanne H. Costin
                                                ---------------------
                                                    Suzanne H. Costin
                                                       Secretary


[CORPORATE SEAL]