I haven't been there in a couple years, but i've always had success with tan and grey scuds size 16 or 18. Brassies and zebra midges in size 18 and smaller are a good idea too. Streamers on a sinking line are a good bet if the water is up, especially sculpin imitations. Good dry fly fishing is pretty rare, but if you find some shallower water a hopper with a scud hung off of it would be worth a shot.
Cheers,
Mike