The Blue – A Treasure Worth Saving

Cutting a large swath through the heart of central Colorado the Blue River runs some 65 miles along the western fringe of the Great Divide. It snakes its way from south to north, flanked on one side by the beautiful Gore Range, to the other the Williams Fork Mountains.

The Blue makes its start in the Ten Mile Range above Breckenridge, CO. From there it dumps into Dillion Reservoir where it’s diverted one of two ways. Some water (the Blue River itself) continues its journey northward until it intersects the Colorado River. The rest is siphoned off through the Roberts Tunnel where it eventually becomes the North Fork of the South Platte River, bringing water to those on the eastern slope of the Continental Divide.

As a beginner fly fisherman the Blue was one of the first rivers I cast a line into. At the time it was still considered a gold medal fishery, and for good reason, the fish and the fishing were amazing! Deep clear plunge pools and long rich runs were stacked full of large healthy trout. All a fisherman needed to do was look for a flash of dark red in the soft current and success was just a dead drift away.

One of my favorite stretches of the Blue is just north of the town of Silverthorne, where the river widens and settles into a slow and gentle cadence. It rolls its way through the sun soaked valley as it weaves in and out of public and private land. Thick stands of cottonwood and pine line its banks and give shade to trout hiding from winged predators and the afternoon heat. If one didn’t know better, they’d think they were in the middle of nowhere.

Since 2016, a good portion of the Blue has lost its gold medal status. Just this past December I fished the stretch between the interstate and the dam and most, if not all, of the big fish had vanished. I’m sure there are still some pigs lurking throughout the river, but the days of having your pick of big fish on the Blue are gone… at least for now.

What has happened to the Blue? How can a river go from gold medal to subpar status in a matter of a few years? Well, fishing pressure is some of it of course, but there are other factors as well. The CPW says one of the major contributors to the Blue’s decline is sub-optimal physical habitat due to low and inconsistent flows coming out of the Dillion Reservoir (100 CFS or less). When certain abiotic factors such as pH, dissolved oxygen, and temperature get out of acceptable range, both insect life (macroinvertebrates) and their food sources (aquatic plants) are compromised. The end result is less bugs for the trout and less trout in the river.

There is no doubt the Blue has some unique challenges when it comes to flow management. Since having to share its water supply with both the Colorado and the South Platte River basins, there are complexities here that most tailwaters don’t have. Factors such as snowpack, temperature and flood control are just a few. Throw in the fact that Dillion Reservoir needs to maintain a certain level to accommodate marina activity, and you have quite the balancing act. It’s no wonder the Blue is in constant flux.

The origin of Colorado’s water is another thing to consider. The average rainfall across our state is roughly 17 inches per year – not a lot. This means we rely heavily on snowpack as our main source of water. With roughly 80 percent of Colorado’s population living on the Eastern Slope, and the majority of the water that supports this population originating on the Western Slope, we are in a constant tug-of-war for our most precious resource. If projections are correct and our state’s population doubles by 2050, we can expect to hear an even louder cry for water from our front range communities over the next 25 years. Can the Blue survive?

The Eagles “The Last Resort”

Who will provide the grand design?
What is yours and what is mine?
Cause there is no more new frontier
We have got to make it here…

They call it paradise
I don’t know why
You call someplace paradise
Kiss it goodbye

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