Fly Fishing Stream Conditions Report: Blue River - Below Dillon Reservoir Silverthorne

This year: The tailwater stretch immediately below Dillon Reservoir is flowing consistently around 54 CFS to 70 CFS, providing clear and cold water with temperatures averaging around 43 degrees. It remains one of the more dependable late-summer fisheries, though the low flows demand highly technical tailwater tactics. Tighten up your presentation in town with 5x or 6x tippet, minimal weight, and flawless drifts. Downstream and north of Silverthorne, the fishing opens up to different strategies. Hopper-dropper rigs have been highly effective, with guides finding good success on both the dry and the trailing nymph. If you head north into the public stretches, don't hesitate to increase your dry fly size and incorporate stonefly patterns into your setup. During hot afternoons on the lower, downstream reaches, keep an eye on water temperatures to ensure the trout are not overly stressed. Nymphing is the core producer, especially under a small, inconspicuous indicator. Focus on tiny midges and mayfly nymphs without flashy beads, as well as local favorites like the RS2 and WD40 in sizes 22 to 24. Be on the lookout for rising fish in the slick pools or pocket water, where a delicate dry fly or a well-placed grasshopper pattern can trigger a quick eat.

Best time of day: Afternoon

Prior years: Anglers can expect excellent fishing conditions below the reservoir. The flow is good, bringing clear and cold water with steady releases from Dillon Dam. The perfect tailwater clarity offers exceptional sight-fishing opportunities as consistent mysis shrimp flushes keep large rainbow trout glued to their feeding lanes, while sparse midges provide additional activity. Due to the highly clear water, stealth is absolutely paramount. If you can see the fish, they can see you. To find success, stay low, cast from an off-angle, and ensure your drift is absolutely perfect.