X0303 4 2008-09-08 0 0000073020 NORTHWEST NATURAL GAS CO NWN 0001192773 DODSON MARK S 220 NW SECOND AVENUE PORTLAND OR 97209-3991 1 1 0 0 Chief Executive Officer Common Stock 2008-09-08 4 M 0 2500 31.34 A 53507.849 D Common Stock 2008-09-08 4 S 0 2500 48.1220 D 51007.849 D Common Stock 516.0057 I See footnote Employee Stock Option to Buy 31.34 2008-09-08 4 M 0 2500 0 D 2014-03-04 Common Stock 2500 15000 D The sale of Northwest Natural Gas Company stock took place in 11 seperate broker transactions occurring on 09/08/2008. The price in column 4 represents the weighted average sale price for the transactions reported on this line. The range of prices for these transactions was $48.00-$48.21. Northwest Natural Gas Company will provide upon request by the Commission staff or a security holder of Northwest Natural Gas Company full information regarding the number of shares purchased or sold at each separate price. Shares were held in the reporting person's account under Northwest Natural Gas Company's Retirement K Savings Plan as of August 31, 2008. Option was granted for 30,000 shares pursuant to Northwest Natural Gas Company's Restated Stock Option Plan. The option fully vested on January 1, 2007. Shawn M. Filippi, Attorney-in-Fact 2008-09-09