These images are in Bonneville Power Administration's photo archive. Those of FDR are from his presidential library (so I am told), some are from the Oregon Historical Association (and so noted when used on the site) and the rest are from unknown sources. All images came from the BPA archive.
All images link to a larger version.
Aircraft production relied upon a large labor pool, lots of land, and even more aluminum. To make all the aluminum that is put onto an aircraft required lots of electricity - and that is where the Pacific Northwest excelled at the beginning of the war.

B-17 Flying Fortress cockpits under contruction
B-17 cockpits under construction on the Seattle production line.
These are B-17F models.
To get out of the depression the US Government spent massively - in the same manner that Germany borrowed and spent themselves out of depression (modern term: Reganomics) and in the US massive public works in the form of power generation dams were one of the many ways used to get the economy going again.
Bonneville Dam, built roughly 40 miles upstream from Portland along the Columbia River, was the first dam built by the Corps of Engineers on the Columbia. To delivery and sell the power generated Bonneville Power Administration was created. This low cost (i.e.: cost recovery only) selling of electricity in turn allowed aluminum smelters to move to the NW to build factories - they use enormous amount of electricity to create the aluminum - that allowed them to make the new product and sell it at a price other companies could afford to pay for it. This allowed more people to be employed, generate more money in the economy, and with people employed money they earned and spent by the borrowing of money to build a dam in the long term would lift the US out of the depression.
The Federal Government policy of selling of electricity at cost (instead of the normal 30% profit margin), the need for lots of aluminum, the need for lots of planes, allowed Boeing to expand and build new plants in Washington to meet the needs of WW II. See this paper on Bonneville Dam's contribution to the war effort (PDF)

Boeing women workers at Seattle in WWII Women and men of Boeing s
riveting parts to fuselage. These are B-17G tail sections.
"A 'Rosie' riveting B-17 tail sheet metal on to longerons.
"Rosie"
riveting skin onto the tail of a B-17F. Compare the tail with the one
above and you can see the different stages in construction.

Two momen working inside a B-17 at Seattle production plant
Colorized
version of a monochrome photograph showing women war plant
workers in
the bomb
bay area of a B-17.

FDR
touring Seattle B-17 plant
FDR, President Franklin Delano Roosevelt, did lots of wartime tours.
This was taken while he was touring the Boeing Seattle plant on September
22. B-17Fs were under production during this timeframe. FDR did a nationwide train
tour of key war plants in September and October of 1942.

FDR passing in front of a nose of a B-17F Fortress on September 22, 1942 while touring the Seattle plant in his car.
Touring the last part of the production line of B-17Fs before they went to the paint shop.
Looking down into FDR's car at Boeing while on his tour.
Someone on an airplane perhaps took this image of FDR at Seattle.

B-17 number 5000 shown inside the Seattle plant.
The 5000th Boeing B-17 Flying Fortress was signed by every worker in the plant and there was a big ceremony when it rolled out of the plant. This photos shows it while still inside the plant.
At its peak efficiency, the Seattle plant turned out 16 complete B-17s a day.

B-17 Fortresses lined up outside Boeing Seattle plant
These G model Flying Fortresses just off the production line in Seattle await delivery to the combat modification center in Kansas. Foreground a/c tail number is 297384, then 298385, 297386 and so on.
The very last B-17 rolled off the production line on April 13, 1945. On that date the Seattle Boeing factory plant completed the conversion to the production of the Boeing B-29.
There is a Seattle Times photo of the switchover ceremony as the last B-17 came out the door.
The Kansas combat modifcation center existed since not all modifications could be incorporated into the production line without disrupting it. So, while all the planning and parts were being designed for smooth incorporation into the 4 plants, all these modificatioins were instead were performed in Kansas. Another set of combat modifications occured once the planes went to England / Italy.