Renovating a Stretch of the San Juan River

By Bob Lusk

The San Juan River starts around 10,000 feet above sea level in the mountains outside Pagosa Springs, Colorado and meanders southwest. It’s a major tributary of the Colorado River, which is famous for eons of work forming the Grand Canyon. That whole river system is crucial to provide much needed water for a huge part of the southwestern United States as well as parts of California.

The San Juan actually flows almost 400 miles, rolling through Colorado, part of northern New Mexico, across southern Utah, then into the Colorado in Glen Canyon.

The San Juan also made national news in 2015 when the EPA accidently dumped more than 3 million gallons of highly acidic wastewater from the Gold King mine outside Silverton, Colorado, turning the river orange and threatening the water supply downstream.

Mike Otto and I took a much-needed road trip through Pagosa Springs back in August. An extraordinary earthmover, Mike McDonald took a full day and toured us around that part of the country. One of the most interesting parts of the tour was along a two mile stretch of that river.

Former Pond Boss partner and long-time friend, Sherman Wyman, bought some property along the river and was interested to see what could be done to improve the fishing.

Who does that, right?

The river, through that area, is flat and shallow. Zero habitat for fish, other than little ones…think minnows.

Other people upstream, had done some incredible work on the river to create diverse habitat, using the flow dynamics of the river to cut channels, create eddies, and riffles where fish can migrate naturally.

The river flow rate ebbs and flows with snow melt. There are times when the river rolls beyond 9,000 cubic feet per second, and times it’s more like 2,500. For those of us who can’t visualize that volume, a cubic foot of water is about 7.5 gallons. 9,000 cubic feet per second would raise a football field 150 feet per minute.

That’s substantial.

Using that flow rate, funneled, channeled and organized, a river can create its own valuable habitat.

That’s part of what Mike McDonald does for a living.

First off, no one just goes out, drives a piece of heavy machinery onto a shallow river bottom and goes to work.

As you can imagine, there’s substantial amounts of permitting to wade through before digging into any river in this country, especially Colorado.

Past that part, the actual renovation is truly an engineering feat. Executing the plan is an exercise in ingenuity, bolstered with a strong understanding how a river works. That means judging what to do, where to do it, and how to do it to make sure what you do stays where you do it.

That part of the river where Sherman’s place sits is loaded with giant rocks, boulders bigger than a pickup truck. The shoreline also has an abundance of trees, especially cottonwoods…big cottonwoods.

The team collaborated on the different types of structures to build, and when to do it. They had to do all the construction at low flow. Fortunately, flow rate was less than 1,500 cubic feet per second when they did the construction.

Several of the units were shaped like a “W”, with the crotch of the “W” facing downstream. Burying giant boulders deep into the river bottom, like an iceberg, McDonald meticulously placed them like a short waterfall, where water flows over the top of the “W”, gouging a hole as deep as fifteen feet in the crotch. Water then cascades forcefully downstream, cutting a deeper channel in the middle of the river rather that spreading out like a sheet as the river did before.

To shore up the bank, and minimize eons of erosion, the team buried some of those big cottonwood logs far into the sides, with root balls angled downstream. That pushes water away from the river bank, keeping the hydraulic force funneled to the middle. While that’s happening, those big root balls are reputable habitat for fish.

For about two miles along that river, different features were installed to use the force of high-water flow to create great habitat for the rives natural fishery.

I asked Sherman what fishing was like. The smile on his face told the tale. I was thinking trout more than anything. That’s true, but since his stretch of the river sits upstream from the Navajo Reservoir, he’s caught everything from rainbow trout, brookies, to big channel catfish and hybrid stripers that made their way upstream during high flow.

How does this affect you? It probably doesn’t but I’ll bet enough of you have a small intermittent stream on your place that the cattle have pounded down for decades that could use an affordable facelift.

Oh, for those of you reading and wondering what this little project cost? It wasn’t cheap, but from an ecological and environmental viewpoint, it was worth it to Sherman Wyman. When I asked him what it cost, he just winked and smiled. I guessed a lifetime of working, building assets and cashing in made it worth it.

A least when he uses a 7-weight flyrod and his favorite fly du jour.