Expect small bugs to be your best bet and the lower reaches around Pleasure Park will be the only options easier to access. Go small and fish the deeper slots and runs.
Patterns/Bugs:
Small bug land:
Two Bit Hooker 16-20, RS2 20-24, Black Midge Pupa 18-22. San Juan Worms and Eggs
Happening Now: Fishing well both upstream and down from the confluence of the north fork. With the river at winter flows your able to wade around more and even cross in some places. The cold weather has pushed them back to the deep holes so make sure you bring some weight to get your small flies down. Small fly season is now so dust off those 18-22 flies and you should find fish.
Most Productive: Nymphing midge pupa and mayfly emergers will produce some nice fish. The fish have moved back into the deeper holes, so get those flies deep with long drifts and you should find some fish.