10-K/A

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D. C. 20549

FORM 10-K/A

(Amendment No. 1)

(Mark One)

[X] ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2008

OR

[    ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from                      to                     

Commission file number 1-15973

NORTHWEST NATURAL GAS COMPANY

(Exact name of registrant as specified in its charter)

Oregon	93-0256722
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)

220 N.W. Second Avenue, Portland, Oregon 97209

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code: (503) 226-4211

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Common Stock Name of each exchange on which registered New York Stock Exchange

Securities registered pursuant to Section 12(g) of the Act: None.

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes [ X ] No [    ]

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes [    ] No [ X ]

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes [ X ] No [    ]

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. [    ]

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See definitions of “accelerated filer,” “large accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):

Large Accelerated Filer [ X ]	Accelerated Filer [    ]
Non-accelerated filer [    ]	Smaller Reporting Company [    ]

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes [    ] No [ X ]

As of June 30, 2008, the registrant had 26,435,373 shares of its Common Stock outstanding. The aggregate market value of these shares of Common Stock (based upon the closing price of these shares on the New York Stock Exchange on that date) held by non-affiliates was $1,211,499,354.

At February 23, 2009, 26,501,188 shares of the registrant’s Common Stock (the only class of Common Stock) were outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the Proxy Statement of the registrant’s, to be filed in connection with the 2009 Annual Meeting of Shareholders, are incorporated by reference in Part III.

EXPLANATORY NOTE

Northwest Natural Gas Company (“NW Natural”) is filing this amended annual report on Form 10-K/A solely to correct typographical errors on the cover page of its annual report on Form 10-K for the fiscal year ended December 31, 2008 (the “Original Filing”). The cover of the Original Filing is being amended to indicate that NW Natural is a well-known seasoned issuer as defined in Rule 405 of the Securities Act of 1933. The cover is also being amended to check the “No” box, beside the statement regarding whether NW Natural is not required to file reports pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934.

Except as described above, no other changes have been made to the Original Filing and this annual report on Form 10-K/A does not amend, update or change the financial statements or any other items or disclosures in the Original Filing.

EXHIBIT INDEX

Exhibit Number	Page
31.1(a)	4
31.2(a)	5

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

	NORTHWEST NATURAL GAS COMPANY
Date: March 6, 2009	By:	/s/ David H. Anderson
		David H. Anderson, Senior Vice President and Chief Financial Officer

3

EX-31.1(A)

EXHIBIT 31.1(a)

CERTIFICATION

I, Gregg S. Kantor, certify that:

1. I have reviewed this annual report on Form 10-K/A of Northwest Natural Gas Company; and

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report.

Date: March 6, 2009

/s/ Gregg S. Kantor

Gregg S. Kantor

President and Chief Executive Officer

4

EX-31.2(A)

EXHIBIT 31.2(a)

CERTIFICATION

I, David H. Anderson, certify that:

1. I have reviewed this annual report on Form 10-K/A of Northwest Natural Gas Company; and

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report.

Date: March 6, 2009

/s/ David H. Anderson

David H. Anderson

Senior Vice President and Chief Financial Officer

5