Pricing supplement no. 5                            Filing under Rule 424(b)(3)
dated September 20, 2002                            Registration No. 333-55366

(To prospectus dated February 27, 2001)




                                  $108,000,000
                          NORTHWEST NATURAL GAS COMPANY
                       SECURED MEDIUM-TERM NOTES, SERIES B
                       (A SERIES OF FIRST MORTGAGE BONDS)
                                       AND
                      UNSECURED MEDIUM-TERM NOTES, SERIES B
               Due from Nine Months to 30 Years from Date of Issue


                                              
CUSIP No.:  66765R BQ 8                          Selling Agent(s): Merrill Lynch & Co.
                                                                                       -----
                                                             UBS Warburg LLC   X
                                                                             -----
Secured   X     Unsecured                                    Banc One Capital Markets, Inc.   X
        -----             -----                                                             -----

Principal amount ($): $30,000,000                            U.S. Bancorp Piper Jaffray Inc.   X
                                                                                             -----
Issue price (%):  100.000%
                                                 Stated interest rate (%):  5.82%
Selling Agent's commission (%):  .750%
                                                 Maturity date:  September 24, 2032
Proceeds to Company (%):  99.250%
                                                 Original issue date:  September 24, 2002
Repayable at the option of holder:
Yes        No   X                                Interest payment dates:  June 1 and December 1,
    -----     -----                              commencing December 1, 2002

   Repayment Date:  Not Applicable               Regular record dates:  May 15 and November 15

   Repayment Price:  Not Applicable              Redeemable:  Yes        No   X
                                                                 -----      -----
   Election Period:  Not Applicable                  In whole
                                                              -----
   Other Terms:  Not Applicable                      In whole or in part
                                                                         -----

                                                 Initial redemption date:  Not Applicable

                                                 Initial redemption price:  Not Applicable

                                                 Reduction Percentage:  Not Applicable

                                                 Redemption limitation date:  Not Applicable

        Agency Transaction  |_|*
                  or
        Principal Transaction |X|*

        Name of Principal(s):  UBS Warburg LLC
                               Banc One Capital Markets, Inc.
                               U.S. Bancorp Piper Jaffray Inc.



*If the Agency Transaction box is checked, the notes are being offered directly
by Northwest Natural Gas Company through any Agent, acting as agent for
Northwest Natural Gas Company. If the Principal Transaction box is checked,
however, the notes have been sold to the Agent(s), as principal, for resale to
purchasers upon terms described in the prospectus, dated February 27, 2001 and
this pricing supplement. If the Principal Transaction box is checked, the notes
are being offered by the Agent(s), as principal, at a price to the public set
forth above under "Issue price (%)"; the notes were purchased by the Agent(s),
as principal, from Northwest Natural Gas Company at the price set forth above
under "Proceeds to Company (%)"; and the Agent(s) received a fee equal to the
difference, which is set forth above under "Selling Agent's commission (%)" as a
percentage of the principal amount of the notes.

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NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES
COMMISSION HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR DETERMINED IF THIS
PRICING SUPPLEMENT OR THE ACCOMPANYING PROSPECTUS IS TRUTHFUL OR COMPLETE. ANY
REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

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