The Clackamas River in the Carver area and above should be getting into shape for steelhead by then.
Since you will be visiting you might consider talking to Jack about going fishing on the Washington side of the Columbia. Couple rivers just north of Portland do pretty well on the Steelhead runs.
Winter steelhead winds down at the end of march but there r still plenty of fish around. Spring salmon will be available too. There is not much in the way of trout fishing in the Portland area....you'll have to drive 11/2 to 2 hrs for that. The rivers here r mostly large and are fished best by boat. The nearby Sandy river has decent bank access for steelhead. The Deschutes river is about 2 hrs east and offers the best chance for trout and has plenty of bank access. It is in a high desert canyon, holds many nice native rainbows and is beautiful. Overall, I highly suggest that u hire a guide for any river u plan to fish since each river has its peculiarities and can be problematic in offering a productive day of angling. Tell jack(owner),at NWFF outfitters that we have chatted and perhaps he can help u out further. I am a retired fly fishing guide and am not in the loop so much as jack is these days. Good luck and enjoy
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