I think most of the rivers and streams are down and fishable now. The exception is the Logan. It's still to high for me, although, I know others who are fishing it now. The upper stretches opened this past weekend so I'll probably take a trip up sometime this week.
I've been fishing the Blacksmith Fork and it's tributaries, and have been catching my share of 8 to 14 inch trout. The tributaries have been fun with larger dry flies. I've been slinging a size 12 Looped Foam Cicada: black body with an orange, red, or green head. The trout seem to jump right on it. Of course, they may just jump on anything that hits the water. They don't seem to picky on patterns. Stealth is the key to success---along with a good presentation.
I talked with some Utah Division of Wildlife Resource employees last week and they mentioned that the snakes (rattlers) are out and about. I saw a dead one on the road towards the mouth of the canyon and saw a fly fisherman carrying a shed skin up from the bank of the river. Watch your step and where you place your hand when climbing around.
I'm hoping to hit it hard now. I'll try to get pictures to go with the adventures.