Pricing supplement no. 6                             Filing under Rule 424(b)(3)
dated  August 31, 2000                               Registration No. 333-64777

(To prospectus dated January 14, 1999)


                                  $123,000,000
                          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  BJ 4                            Selling Agent(s):Merrill Lynch & Co.
                                                                                        ----
Secured  X    Unsecured                                              PaineWebber Incorporated  X
        ----                                                                                 ----
                                                                     Banc One Capital Markets, Inc.
Principal amount ($): $20,000,000                                                                  ----

Issue price (%): 100.000%                           Stated interest rate (%): 7.72%

Selling Agent's commission (%): .750%               Maturity date:  September 1, 2025

Proceeds to Company (%): 99.250%                    Original issue date: September 6, 2000

Repayable at the option of holder:  Yes     No X    Interest  payment dates:  June 1 and December 1,
                                       ----   ----  commencing December 1, 2000

  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    [X]*
             or
     Principal Transaction [ ]*

     Name of Principal(s): Not Applicable

*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 January 14, 1999 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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