Thinking like a creek
When it comes to land, building resilience in an ecosystem so it can withstand an intense shock often means rebuilding resilience. That’s because so much land exists in a degraded condition today, a consequence of a century of hard use and mismanagement, that its ability to absorb the effects of a prolonged drought or hot fire, say, without further degrading its ecological integrity is a tall order. That’s why restoring land to health has to be one of our top priorities.
Fortunately, the restoration toolbox has been well developed over the past three decades, including innovative strategies for healing damaged riparian areas. I describe two such strategies below. One focuses on a pioneering methodology for re-meandering creeks developed by Bill Zeedyk and the second features an artistic approach to creek restoration developed by Craig Sponholtz. Both strategies are effective, attractive, and necessary to rebuilding resilience in the 21st century.
During my travels, I heard a story about a man who had put short fences across a cattle trail in the sandy bottom of a canyon in Navajo country so that cattle were forced to meander in an S-pattern as they walked, encouraging the water to meander too and thus slow erosion. I thought this idea was wonderfully heretical. That’s because the standard solution for degraded creeks is spend a bunch of money on cement, riprap, and diesel-driven machines. Putting fences in the way of cattle and letting them do the work? How cool.
The man was Bill Zeedyk, a retired biologist with the U.S. Forest Service reincarnated as a riparian restoration specialist. Was the story true, I asked him? It was, he assured me. Recognizing that water running down a straight trail will cut a deeper and deeper incision in soft soil with each storm, Bill talked the local Navajo ranchers into placing fences at intervals along the trail so that the cows would be forced to create a meander pattern in the soil precisely where Bill thought nature would do so in their absence. Water likes to meander – it’s nature’s way of dissipating energy – and it will gravitate toward doing so do even if it’s temporarily trapped in a cattle-caused rut (or human-caused hiking trail). His fence idea was a way to move the process along.
What happened after the fences were put it in? The water table came up as vegetation grew back, Bill replied, because the water was now traveling more slowly as a result and had a chance to percolate into the ground, rather than run off like before. Eroded banks began to revegetate as the water table rose and more water appeared in the bottom of the canyon, which encouraged riparian plant growth.
“Nature did all the heavy lifting,” he said, before adding a warm, knowing smile. “It worked too, until someone stole the fences.”
Over the years, Bill has developed a very effective set of low-cost techniques that reduce erosion, return riparian areas to a healthier functioning condition, and restore wet meadows. This is important because a big part of the West exists in an eroded condition, generally the result of historically poor land management. This point was brought home to me in force one day when I walked under a barbed wire fence that stretched across a gully on a New Mexico ranch. The fence was five feet above my head. The rancher told me that the fence was built in 1937 and the fence posts originally rested on the ground!
To heal this type of damage, Bill has put together a toolbox designed to “heal nature with nature” that includes:
• one-rock dams/weirs – grade-control structures composed of wooden pickets or rocks that are literally one-rock high and simulate a ‘riffle’ effect in creeks.
• baffles/deflectors – wedge-shaped structures that steer water flow.
• vanes – a row of posts that project upstream to deflect water away from eroding banks.
• headcut control structures/rock bowls – to slow or stop the relentless march of erosion up a creek and trap water so vegetation can grow.
• worm ditches – to redirect water away from headcuts in wet meadows.
The goal of these structures is to stop downcutting in creeks, often by ‘inducing’ an incised stream to return to a “dynamically stable” channel through the power of small flood events. Bill calls it Induced Meandering. When a creek loses its riparian vegetation – grasses, sedges, rushes, willows and other water-loving plants, it tends to straighten out and cut downward because the speed of water is now greater, causing the scouring power of sediment to increase. Over time, this downcutting results in the creek becoming entrenched below its original floodplain, which causes all sorts of ecological havoc, including a drop in the water table. Eventually, the creek will create a new floodplain at this lower level by remeandering itself, but that’s a process that often takes decades. Bill’s idea is to goose the process along by forcing the creek to remeander itself his vanes, baffles, and riffle weirs carefully calculated and emplaced. And once water begins to slow down, guess what begins to grow? Willows, sedges, and rushes!
“My aim is to armor eroded streambanks the old fashioned way,” said Bill, “with green, growing plants, not with cement and rock gabions.”
The employment of one-rock dams typifies Bill’s naturalistic approach. The conventional response of landowners to eroded, downcut streams and arroyos has been to build check dams in the middle of the water course. The old idea was to trap sediment behind a dam, which would give vegetation a place to take root as moisture is captured and stored. The trouble is check dams work against nature’s long-term plans.
“All check dams, big or small, are doomed to fail,” said Bill. “That’s because nature has a lot more time than we do. As water does its work, especially during floods, the dam will undercut and eventually collapse, sending all that sediment downstream and making things worse than if you did nothing at all.”
“The trick is to think like a creek,” he continued. “As someone once told me long ago, creeks don’t like to be lakes, even tiny ones. Over time, they’ll be creeks again.”
One-rock dams, by contrast, don’t collapse – because they are only one-rock high. Instead, they slow water down, capture sediment, store a bit of moisture and give vegetation a place to take root. It just takes more time to see the effect.
“As a species, we humans want immediate results. But nature often has the last word,” said Bill. “It took 150 years to get the land into this condition; it’s going to take at least as long to get it repaired.” The key is to learn how to read the landscape – to become literate in the language of ecological health.
“All ecological change is a matter of process. I try to learn the process and let nature do the work,” said Bill, “but you’ve got to understand the process, because if you don’t, you can’t fix the problem.”
Over fifteen years and across a dozen states, Bill has implemented hundreds of restoration projects, healing miles of riparian areas – all by thinking like a creek!
Form + Function
One of my heroes is the conservationist Aldo Leopold, widely honored for his pioneering work in many fields of endeavor, including wilderness protection, wildlife management, environmental education, and even sustainable agriculture. While he is best known for his articulation of a land ethic, which is essentially a plea for harmony between land and people, as well as the concept of land health, which encompassed the regenerative processes that perpetuate life, there is another aspect of his deep thinking that has been largely overlooked: beauty is also an important component of conservation. In Leopold’s own words:
“There is only one soil, one flora, one fauna, and one people, and hence only one conservation problem…economic and esthetic land uses can and must be integrated, usually on the same acre.” [Land Pathology, 1935]
“Bread and beauty grow best together. Their harmonious integration can make farming not only a business but an art; the land not only a food-factory but an instrument for self-expression, on which each can play music of his own choosing.” [The Conservation Ethic, 1933]
Art, harmony, beauty and aesthetics are all signs of health in nature and ourselves. This was one of the reasons I took a shine to Bill Zeedyk’s ideas about creek restoration. Bill’s methods harmonized with the land and its ecological processes. Not coincidently, his structures were also attractive to look at. Made of rocks and wooden posts, they had a sculptural feel that verged on the artistic. It was work that integrated form and function on one acre – just as Leopold had hoped.
One of Bill Zeedyk’s students, Craig Sponholtz, has taken this idea to the next level, transforming stream restoration into an art form.
For example, Craig recently debuted a log-and-rock structure he calls a “step-down” in Grassy Creek, high the Valle Vidal unit of the Carson National Forest of northern New Mexico, that was not only impressively constructed but lovely to look at. Craig had arranged zigzagged spruce logs in the creek to make it look like the trees had simply toppled over from the nearby forest instead of having been carefully placed by a machine (an excavator in this case). Locally-sourced rocks had also been fitted around the logs in a way that was pleasing to the eye. Add in the tufts of sod inserted between the rocks and logs and the sound of cascading water, and you had the recipe for a Zen-like work of art.
Of course, the step-down structure had a job to do, first and foremost. Its assignment was to save a wet meadow above it by easing water down a steep stretch of creek that had developed a big headcut without incurring any additional erosion. Accomplishing this goal requires knowledge of soils, hydrology, geomorphology, mechanical engineering and math on the part of the designer, as well a great deal of field experience (and a soft touch with an excavator) or the structure will fail in its duty. But this is where Leopold came in. What Craig had done on Grassy was take something functional and human-constructed and make it look like a natural feature on the land, in this case an attractive log-filled cascade of merry water.
It was a wholly practical restoration structure and a piece of sculpture. It demonstrated that the principles that made a practice regenerative were the same ones that made it beautiful.
Leopold is an inspiration to Craig as well. His favorite quote is this one: “A thing is right when it tends to preserve the integrity, stability and beauty of the biotic community. It is wrong when it tends otherwise.” That’s exactly what the log-and-rock step-down is doing – restoring the integrity, stability, and beauty of the biotic community known as Grassy Creek.
“If you’re going to spend time and money trying to heal a meadow like this, which is critically important to the ecosystem,” Craig told me, “then I think it’s best to follow nature’s blueprints, which involves an intricate web of interactions that life depends on. Beauty is part of that web, as are water, soil and plants. You can’t have one without the other.”
Of Craig’s work, especially lovely is the water-spreading, crescent-shaped structure called a media luna (half moon) which he has perfected into sculpture. Another specialty is an in-stream grade-control structure called a cross vane, which is composed of large rocks carefully arranged in the creek in order to slow down the water’s momentum by creating a natural plunge pool.
After taking care to read the landscape of the project site diligently, Craig creates a design that involves as few people and materials and as little dirt-moving as possible, while striving for a strong and long-lasting effect. This minimalism is partly about self-expression, but it also about physical objectives – to heal the creek as simply and effectively as possible. It also makes sense economically, especially to the landowner or agency funding the work. Beauty is woven into the minimalism too, which accounts for naturalistic feel of his structures.
Craig calls what he does “regenerative earth art.” Not only is his goal to heal damaged land for anyone who lives in a watershed (all of us, in other words), he creates structures that become part of the ecological processes that they reignite. By serving as footholds for grass and riparian plants that take over, his structures eventually are absorbed into the land itself and disappear. Best of all, this integration of the ecological and the aesthetic can happen anywhere, even in cities.
“The main misconception that people have about watershed restoration,” Craig said, “is that it’s something that happens far away in parks and public lands and not something that can be part of everyday life. But everyone lives in a watershed and I work hard to make the restoration of our home watersheds something that is built into the ways we live and work.”
For more on Bill Zeedyk’s Induced Meandering methodology see the manual: Let the Water Do the Work, available from Chelsea Green Press in June, 2014.
Craig Sponholtz’s web site: http://drylandsolutions.com/
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