forum, so I missed this request for Portland info for a long while.
City Chickens was set up by a Portland chicken-keeper. I believe that she now lives north of the river, in Washington State. Along with everything else, she has a lot of information on her website for folks who have chickens in Portland and surrounding cities.
I live in Beaverton Oregon and I have more than what is allowed. I'm kinda on the outskirts, but not really. In the town i'm in does not allow even 1!!! Roosters are prohibited and I have 1,ok 3. I guess it depends on where you live and the neighbors that live around you. My roos are not the most quiet ones either!!