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Winter Trout on the Blue River

Winter Trout on the Blue River

This Colorado flow promises to be just as action-packed and memorable as ever this winter. Here's where you might just catch that trout of a lifetime!

Ian Davis of Breckenridge Outfitters lifts a 7-pound Blue River rainbow from the waters beneath the I-70 bridge downstream of Dillon Reservoir. Photo by Glenn Bamburg

Approaching from downstream, I moved to within a rod's length of a gigantic rainbow trout spotted from the bank. I knew the brute would allow only a cast or two before retreating to the restricted zone below the dam. Tossing a No. 20 Black Beauty into the feeding lane, I high-sticked the imitation, eagerly awaiting a strike.

Within seconds, a gaping white mouth inhaled the fly. Setting the hook, I anticipated a customary race downriver, but the runaway fish headed upstream against the current, seeking sanctuary in a section off limits to anglers. The struggle was brief, and before long, I gently removed my barbless hook from the 10-pound, Blue River rainbow.

Overhead on Interstate 70, drivers raced their autos along the freeway, oblivious to the mountain stream passing beneath them. The chatter of bargain hunters drifted upriver from dozens of outlet stores lining snowy banks through Silverthorne's business district, and the aroma of restaurant cuisine permeated the frosty air. The Blue River tailwater below Dillon Reservoir is clearly an urban fishery.

With headwaters near Hoosier Pass, the Blue River begins at the juncture of Monte Cristo and Bemrose creeks and tumbles 15 miles north through Breckenridge into Dillon Reservoir. Escaping at Silverthorne, the river winds 35 miles northwest, merging with the Colorado River at Kremmling.

In past years, the Blue River provided a safe haven for trout. However, recent surveys indicate fewer fish. Habitat pollution, inadequate stocking, low flows, poaching and whirling disease are likely culprits.

"There are definitely fewer trout," confirmed Ian Davis, guide and co-owner of Breckenridge Outfitters. "I've heard 50 to 150 less fish per mile, but DOW stocked the river last summer, so I can't give accurate counts.

"The number one problem is low flows by the Denver Water Board taking more water through Roberts Tunnel and shipping it to Denver and not letting it flow down the Blue as it has traditionally," he explained. "The DWB is not going to bring flows above 55 cfs this year. That's a minimum flow and that's what they're going to give us."

Fortunately, the river's long-term future appears to be bright. The DWB, Silverthorne, the CDOW and others seek to protect the stream's Gold Medal status by constructing fish habitat enhancement structures, maintaining adequate stream flows and preserving water quality.

Despite the recent downturn in fish numbers, fishing below Dillon Dam is impressive. Rainbow trout concentrate in this section, growing to mammoth proportions by feeding on mysis shrimp from Dillon Reservoir. Large brown trout also patrol these waters, and respectable brookies and cutthroats are regularly netted.

"The tailwater section is very productive," reported Davis. "There's still a lot of fish in the first seven miles. The river through Silverthorne probably remains in the Gold Medal category or close to it, but the lower section is definitely not what it used to be, although it provides great fishing at times."

Larger rainbows run 4 to 8 pounds in the tailwater, with 10- to 15-pounders routinely landed. Smaller 'bows average 16 to 20 inches, while browns measure 12 to 16 inches up to 7 pounds. Brook and cutthroat trout range 10 to 14 inches, including occasional 18-inchers.

"In winter, more fish congregate by the dam because it's a warmer flow," observed Davis. "The water doesn't freeze and there's a good, consistent food supply of mysis shrimp and midge hatches. Water temperatures range from 34 to 38 degrees, usually keeping the river fishable 10 to 15 miles downstream."

Planted in Dillon Reservoir as forage for kokanee salmon, mysis shrimp have greatly benefited Blue River trout, as Dillon's bottom-release dam flushes thousands of them downstream. Trout feast on the high-protein crustaceans.

The shrimp get chewed up and most are dead when they come out of the turbines. "Trout expend little energy capturing them," said Davis. "Mysis are normally available in the first two miles below the dam."

Mysis supply nutrients all year, a bonus during winter when insect hatches diminish. Mayflies, midges, caddis and stoneflies also provide immature larvae and pupae during the cold season. Midges hatch frequently in January, bringing trout to the surface between 11 a.m. and 2 p.m.

Proven tailwater patterns include No. 16-18 Burton's Mysis Shrimp, No. 16-24 Brassie, No. 18-20 Black Biot Midge, No. 18-22 Miracle Nymph, No. 18-24 Black Beauty Midge, No. 16-22 Pheasant Tail Nymph, No. 18-22 Palomino Midge and No. 16-22 Griffith's Gnat.

Terminal tackle is crucial. Older, wiser trout shy away from anything appearing abnormal or unnatural. The stream's crystal-clear flows magnify the fish's visual acuity, requiring the use of low-profile leaders and tippets.

"I recommend a 9-foot, 5x fluorocarbon leader with 6x tippet for any catch-and-release water in Colorado," advised Davis. "Fluorocarbon doesn't reflect light, has the same density as water and is more abrasion resistant. It has more 'invisible' properties than monofilament leader."

Place a yarn indicator on the leader at twice the water depth and add weight above the knot between the leader and tippet until flies drift near the bottom without snagging too often. A fast-action, 9-foot, 5-weight soft-tip fly rod breaks fewer tippets.

"When spot fishing, I prefer one fly because it's easier to change patterns," said Davis. " Once a fish gets a good look at your imitation and nothing happens, it's important to change patterns. If casting two flies, I've found fish will often spook off a bigger first fly, unless they're eating mysis shrimp. Two flies are advisable when you're prospecting or blind casting."

Before casting, search for foraging trout. Look for a red stripe, dark silhouette or white mouth. In low flows, they're easy to spot with polarized sunglasses. Wear drab clothing and walk slowly, using streamside vegetation and shadows for conceal


"Larger rainbows hold in deeper, slower sections during winter," noted Davis, "along current seams with a good view of drifting food in the faster water. They'll sit in slower flows to conserve energy and eat tidbits from the faster lane. Brown trout move around as the day warms up, getting closer to shore under bushes and undercut banks.

"After spotting a fish, approach it from downstream," he suggested. "You should be able to get within 20 or 30 feet and use a reach cast. Watch the yarn indicator closely, lifting the rod tip gently when the fish strikes."

The Blue River tailwater from Dillon Dam downstream to the north city limits of Silverthorne (about three miles) is catch-and-release, artificial flies or lures only. From Silverthorne's north city limits to the Colorado River, anglers may keep two trout, 16 inches or longer but artificial flies or lures are required.

Silverthorne Lodging
Days Inn, 580 Silverthorne Lane, (970) 468-8661.

Luxury Inn, 540 Silverthorne Lane, (970) 468-0800.

1st Interstate Inn, 357 Blue Ridge Pkwy., (970) 468-5170.

Mountain Vista Bed & Breakfast, 358 Lagoon Lane, (970) 468-7700.

Breckenridge Ski Lodges
Breckenridge Mt. Lodge, 1-877-877-7829;

Great Divide Lodge, 1-888-906-5698;

High Country Lodge, 1-800-497-0097,

The Village at Breckenridge Resort 1-877-428-7829,

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