Welcome to the forum Jen.
I do have an idea for you. I don't think anybody has ever really gone out and made a Vanport documentary before. You could do a series based on WWII era ghost towns, with Hanford taking a special episode. Hanford is in the process of being torn down, so its a sort of now-or-never thing. It is so polluted with radiation in places that people are hired to hunt down any rats or rabbits that may have accidentally drunk water at the site. If the rabbits get away from the grounds and defecate, they are spreading deadly radiation in their waste!
This all makes for some very spooky film-making, featuring Chernoble-style tension and scenes of abandonment.
There are a few WWII ghost towns in America that people are only vaguely aware of. Hanford nuclear reservation has it's own ghost town that housed the workers, but for the moment the name of it escapes me. There are still people out there living today to interview who lived and worked at these now-abandoned war-era towns and bases. Like I said, it's now or never.
edit: I found a nice snippet of Vanport Flood footage here. Start watching at 15:27.
This is pretty much some of the most dynamic footage of a ghost town being destroyed as you can get. More of it is out there, buried in archives. The local news station probably has lots of footage sitting in the basement that hasn't ever seen the light of day.
It's Portland's shame. Nobody has heard of the 2nd largest city in Oregon that was destroyed in a single day. It's too bad because I think the Portlander's redeemed themselves with their reaction to the flood. It's a very interesting story just waiting to be told.