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Float Fishing the Lower Blue River

The Lower Blue River stretches approximately 15 miles across Summit and Grand Counties from Green Mountain Reservoir to its confluence with the Colorado River.  The river corridor supports a great diversity of natural resources, including wildlife like elk, white tail deer, mule deer, moose, bear, mountain lion, bobcat, river otter, mink, beaver and fox.  Waterfowl is abundant and so are fish eating birds like bald eagles, herons and mergansers.

Land Ownership

Land management along the Lower Blue River consists of a diverse set of land managers, including Bureau of Land Management (BLM), United States Forest Service (USFS), Summit County, Grand County and several private landowners.  Seventy percent of the land surrounding the Blue River is private so float fishing the Lower Blue River is the best way to access. Remember in Colorado, it is illegal to wade or anchor while floating through private water so stay in your boat to avoid a ticket.

Habitat Improvement

Based on the input of biologists, hydrologists, engineers and land planners significant improvements to the physical river habitat have been implemented on private land along the lower reaches of the Blue River. Over a period of 14 years roughly 7.5 miles of river fish habitat was improved, including the restoration of inactive oxbows and side channels. Fields that were formerly in agricultural production were restored to riparian/wetland areas.

Since the abundance of new habitat in the Lower Blue River is still checked by the presence of whirling disease, private landowners have convinced the Colorado Division of Wildlife that the stocking of hatchery reared trout is essential.  Investments in habitat reclamation, rumored to be over $30 million, in conjunction with the water quality in the Blue River below Green Mountain Dam has accounted for fish production to climb from 30-70 lbs per acre to 200-300 lbs per acre on private land.  The construction of deep pools have provided trout refuge during critical periods of low flows in the winter and summer allowing for fish to reach gargantuan proportions, giving  the lower Blue River the name “Jurassic Park”.

The Fishery

The Blue River is designated “Gold Medal”, Wild Trout waters by the Colorado Wildlife Commission within Green Mountain Canyon, which is managed for self-propagating brown trout.  Brown trout populations are presently good to excellent in the canyon, reaching 150 lbs per acre.  Wild brown trout are found throughout the lower Blue and can reach well over two feet long. Rainbows dominate the fishery below the canyon and have been known to reach twenty five pounds. Additionally cutthroats, a few brookies and the occasional whitefish are present.

Float fishing the Lower Blue River in this section is enhanced by the conifer forests of Douglas fir, juniper and pine surrounded by steep cliffs. The Canyon is not an easy row but the wild scenery and fish make it worth the effort.


As stated earlier, there is a mix of public and private property but this float is mostly private. Current public access to float fish the Lower Blue River is provided at Green Mountain Dam “Put-In” which is actually a fifty foot steep hill. The site is part of a 50-year lease held by Summit County from the Bureau of Reclamation.  The site is unimproved, and the boat ramp is steep (60 degrees).  Ropes to belay your raft (drift boats will not negotiate this stretch safely) are necessary to get it safely to the water.

The Yust take-out site is located on private land approximately 12.7 miles from the put-in and about .21 miles downriver of Trough Road Bridge river crossing.  You may also use the Confluence take-out another 2.5 miles downriver where the Blue River empties into the Colorado River.  This BLM put-in/take-out also serves as the access to the class 5 whitewater found in Gore Canyon on the Colorado.


Float fishing the Lower Blue River is a bit tricky; Class 2 and 3 whitewater await the float fisherman in Green Mountain Canyon, below the dam, as steep canyon walls greet the boater. Do not attempt this float if you are not an experienced boater.

During normal periods of high flows, such as spring runoff of winter snowmelt, the natural flows of the Lower Blue actually diminish as water is stored in the reservoir system (except on high water years like this year).  Stored water is then released during the irrigation season.  These extra cold reservoir flows actually serve to cool down the Colorado River in the heat of summer and make float fishing the Upper Colorado River a great mid-summer float fishing option and a few Blue River behemoths always find their way down to Pumphouse.

After floating a couple miles, the fast canyon water gives way to a broader floodplain that provides an easier row through private pasture land.  The water will flow from a low of 60 cfs in the winter to a high around 2,000 cfs most years.  The sweet spot for float fishing the Lower Blue is around 900 cfs and most boats will need at least 600 cfs for safe floating.

Look out for several diversion structures that are found along the river. They are well marked but can be challenging to go over.  Over a dozen man-made drop structures are in this section of river. It can be dangerous to float fish the Lower Blue River. Try to float with another experienced boater and have a plan to communicate and watch out for each other.


Do not bring a lot of gear in case you flip your raft.  A six to eight weight rod equipped with a good reel will be needed.  Bring an extra rod, these fish are hot and breaking rods here is a possibility.  Floating line will be needed but a short sinking head can be used to drop nymphs quickly behind the man-made drop structures.  Bring a large fish friendly net, these rainbows average at least 5 pounds.  Bring a lot of food and extra water, float fishing the lower blue river at lower flows can take up to 12 hours.

You will need some 2x or3x fluorocarbon tippet to handle the big fish on nymph rigs which is usually the most productive method of fishing.  Use 0x or larger for streamer fishing which can be very visual and exciting.

Flies and Hatches

Hatches occur on most days while floating the Blue.  Look for action on midges and BWO’s early and late in the year.  Caddis, PMD’s, Green Drakes and Golden Stones are flies these fish see often in the summer months. Hoppers work well on the meadow stretches and on dark days or in the evening, floating mice patterns waked on the surface will receive crushing strikes.  Non-hatch meals include San Juan Worms, eggs, leeches and weighted streamers. Use flies with heavy wire hooks to minimize the chance of them straightening on a giant trout.

Should you end up deciding to give float fishing the Lower Blue River a try stop by Vail Valley Anglers, Edwards, CO for some more information or a selection of our favorite fly patterns for the Lower Blue River.

Bill Perry, Guide and Content Writer