To be guaranteed that you'll catch fish? Not much within an hour (though if you're a better angler than me which is not hard, then your odds are good)...
In two hours, you're on the Deschutes near Maupin. I just posted a report in the trip reports thread. It was good to me.
Steelhead wise, the SW Washington rivers should be in shape. They are all dropping nicely. The Clack and Sandy have fish in them too. Heck, the S. Santiam has gotten some really good numbers of Summer-heads back already if you don't mind an hour and a half drive and you have steel on the brain.
Also, Shad fishing should continue to build in the Columbia River Gorge. 7 wts and combat fishing near Bonneville but supposedly bad ass if get into them. I've yet to try it but I scoped out the scene while driving to Hood River last week. Bonneville is about 45 minutes from Downtown PDX.
I hooked three shad and a sturgeon fishing a few hours after work last Thursday at Bonneville. The gear guys were into them almost non-stop. It's not easy to fly fish but worth the trip for the experience.