What Dillon Reservoir Offers
Dillon Reservoir is a 3,300-acre impoundment on the Blue River near Silverthorne, Colorado, sitting at 9,017 feet elevation in the central Rocky Mountains. It holds lake trout, rainbow trout, brown trout, and kokanee salmon, with the lake trout population the most reliable year-round fishery. The reservoir is managed by Denver Water and open to the public for fishing under Colorado Parks and Wildlife regulations.
The lake is known for consistent cold-water conditions and steady fishing pressure from both shore and boat anglers. Summer and fall are the most popular seasons, though the reservoir remains fishable through winter when ice conditions permit. Access is straightforward — the lake has three public boat ramps, multiple parking areas, and a marina with rentals and supplies.
Key Takeaways
- Lake trout are the most abundant species and can be caught year-round, with jigging in deep water the most productive method in summer and fall.
- Rainbow and brown trout are present but less consistent than lake trout; they respond better to fly fishing and live bait in spring and early summer.
- Kokanee salmon run in fall, typically August through October, and require small spoons or jigging in deeper basins.
- A Colorado Parks and Wildlife fishing license is required for anyone 16 and older; no special stamp is needed for Dillon Reservoir.
- The lake sits at 9,017 feet, so plan for afternoon thunderstorms in summer and snow or ice conditions from November through March.
Lake Trout Fishing Year-Round
Lake trout dominate Dillon Reservoir and are the most predictable target. They school in deep water during summer and fall, typically 40 to 80 feet down, and respond well to vertical jigging with small spoons (1/4 to 1/2 ounce) in silver or white. Early morning and late afternoon produce the best results, though midday jigging in the deepest basins — particularly near the dam and in the central lake — can yield fish when surface activity is slow.
Winter fishing for lake trout shifts to ice fishing when the lake freezes solid, usually by late November. Jigging through the ice with small spoons or live minnows works consistently. Spring and early summer see lake trout move shallower as water temperatures rise, making them catchable from shore in 15 to 30 feet of water. Fall fishing remains strong through October as water cools again.
Rainbow and Brown Trout in Spring and Early Summer
Rainbow and brown trout are present in Dillon but less abundant than lake trout. They respond best to fly fishing with small nymphs and streamers, particularly in spring (May through June) when water temperatures are coolest. The Blue River inlet on the north end of the reservoir and the shallower bays near the boat ramps hold more rainbows than the main lake body.
Live bait fishing with small shiners or crawfish also produces rainbows and browns, especially from shore in the early morning. By mid-July, as water temperatures climb, these species move deeper and become harder to target consistently. Catch-and-release fishing is common for rainbows and browns, as lake trout are the primary harvest species.
Kokanee Salmon in Late Summer and Fall
Kokanee salmon enter Dillon Reservoir in late summer and peak from August through October. These small landlocked salmon (typically 10 to 14 inches) school in deep water and respond to small spoons, jigging, and trolling. Kokanee fishing requires patience and precise depth control — they hold in specific temperature layers, usually 30 to 60 feet down, and move daily based on water temperature.
Trolling small spoons along the main lake basin or jigging vertically in the deeper holes near the dam are the most effective methods. Kokanee fishing slows significantly after October as the spawning run ends and fish move into tributary streams. The season is short but can produce fast action for anglers willing to fish deep water.
Access, Boat Ramps, and Facilities
Dillon Reservoir has three public boat ramps: the main ramp near the marina on the south shore (accessible from Dillon Dam Road), the Inlet Bay ramp on the north end (near the Blue River inlet), and the Keystone Gulch ramp on the west shore. All three have parking, and the main marina ramp has the most amenities, including a tackle shop, boat rentals, and a restaurant. Parking fills quickly on summer weekends, particularly Saturday and Sunday mornings.
Shore fishing is possible at several locations, including the dam area, Dillon Town Park, and various pullouts along Dillon Dam Road. No special permit is required for shore access on public land. The lake is open year-round, though winter access depends on snow and ice conditions — call the Dillon Marina or check Colorado Parks and Wildlife's website for current conditions before traveling in November through March.
Regulations and Licensing
A Colorado Parks and Wildlife fishing license is required for anyone 16 and older. Licenses can be purchased online through the Colorado Parks and Wildlife website, at the Dillon Marina, or at sporting goods stores in Silverthorne and Keystone. A three-day license is available for visitors who do not want a full-year license.
Dillon Reservoir has standard statewide trout regulations: a possession limit of 10 trout (all species combined), with no more than 5 lake trout. Kokanee salmon have a separate limit of 10 fish. Bait fishing is allowed, and both artificial lures and live bait are effective. Check the current Colorado Parks and Wildlife fishing brochure for any special regulations or closures before your trip.
Seasons and Weather Conditions
Summer (June through August) is the most popular season, with warm days, reliable access, and consistent fishing. Afternoon thunderstorms are common at this elevation and can develop quickly — plan to be off the water by mid-afternoon. Water temperatures range from 55 to 65 degrees Fahrenheit, and lake trout hold deep during the day.
Fall (September through October) offers cooler weather, fewer crowds, and excellent fishing for both lake trout and kokanee. Water temperatures drop to 45 to 55 degrees, and fish move shallower. Winter (November through March) brings snow, ice, and limited access — the lake often freezes solid by late November, and ice fishing is the primary option. Spring (April through May) sees water temperatures rise from 40 to 50 degrees, and fishing improves as the season progresses.
Frequently Asked Questions
What is the best time of year to fish Dillon Reservoir?
Fall (September through October) offers the most consistent fishing and the best weather. Lake trout bite well in deep water, kokanee salmon are active, and crowds are smaller than in summer. Summer is also productive but requires fishing early and late in the day to avoid afternoon thunderstorms.
Can I fish from shore, or do I need a boat?
Shore fishing is possible at several locations, including the dam area and Dillon Town Park. Lake trout are catchable from shore in spring and fall when they move shallower. Summer shore fishing is slower because lake trout hold deep, but it remains an option for anglers without a boat.
How far is Dillon Reservoir from Denver?
Dillon Reservoir is approximately 75 miles west of Denver, near Silverthorne. The drive takes about 90 minutes via Interstate 25 north and US Highway 6 west. The town of Silverthorne has gas, food, and lodging options for visitors planning a full day or overnight trip.
What should I bring for a day of fishing at Dillon?
Bring a Colorado fishing license, sunscreen, a hat, and layers — weather changes quickly at 9,000 feet elevation. If jigging for lake trout, bring small spoons, a depth finder or fish finder if you have a boat, and a cooler for fish. Shore anglers should bring a headlamp for early morning fishing and a rain jacket for afternoon storms.
Is there a fee to launch a boat at Dillon Reservoir?
Yes, boat launch fees vary by ramp and are typically $10 to $15 per day. The main marina ramp near the dam charges a daily fee, and some ramps may charge less. Call the Dillon Marina or check the Denver Water website for current fees before your trip.