Streamers and mayfly nymphs fished on a Stillwater line are also producing. The north side of the lake has been particularly productive. Look for callibaetis hatch to start soon. McCumber is located just east of Shingletown on the way to Manzanita Lake. Float tube or boat needed.
Fishing is fair, and can be good if flows stabilize.
Best action is from midmorning on. Access is along Chalk Bluff Rd. The canyon section above the Reservoir is also good - it requires a hike, but you will get away from crowds. Blown out - water is spilling over the Glory Hole at Lake Berryessa. Need to wait for a couple more weeks - at least.