Sustainable Trail Construction
Once you begin to learn about trail construction methods, you may not be able to look at a trail the same again.
Trail work is not my favourite, I’ll admit. It’s gruelling. Tiring. There are biting bugs. But I often think of something I heard Glenn Plake say in a ski movie: “You can’t evolve without being involved.” My adopted mantra works on many levels. Riders own the responsibility of shaping their riding scene. By showing up to trail work days, public meetings, events, and fundraisers, we build together a vibrant mountain bike community complete with trails we all love to ride. Of course, more support and involvement means more trails. As for my personal evolution, it wasn’t until I became more involved that I could appreciate what it took to deliver the trails I love to ride. That rock is strategic. That berm is engineered to serve a purpose. Those fun little descents in the middle of gruelling climbs weren’t by chance. Our enjoyment is part of trail design for sure, but there’s far more to it than that. You may not put much thought to how your favourite singletrack came to be. But there are many factors contributing to how and where it rides, like terrain, soil type, drainage, landowner agreements, and even history. Once you begin to learn about trail construction methods, you may not be able to look at a trail the same again. The name of the game for trail construction and maintenance is sustainability. This has two meanings: minimizing the impact of the trail and its users to the surrounding environment, and building trails that last. The sustainable construction standards set forth by the International Mountain Bicycling Association and outlined in the book, “Trail Solutions: A Guide to Building Sweet Singletrack” provide much guidance to trail builders around the world. Site selection is a critical first step in planning for the environmental sustainability of a trail. “Not every place is good for a trail,” says Mariah Keagy, Vermont-based trail builder and educator. Mountain bike trails should avoid wet areas, sensitive species and habitat, and important historical sites. Minimizing erosion is the key to sustaining trails over time. Water is a major culprit, but this can be mitigated by including features that
prevent water from collecting on the trail and that reduce erosion from run-off. “Every trail is a stream unless you get the water off of it,” says Keagy. Trail features like grade reversals and French drains, plus construction techniques that include rolling terrain, bench-cutting and sloping the trails downward to the outer edge all help to shed water safely. Minimizing grade on mountain bike trails also reduces erosion from soil being displaced by water and tire treads. IMBA’s Half Rule states that a trail’s grade shouldn’t exceed half the grade of the hillside. The Ten Percent Average Guideline and Maximum Sustainable Trail Grade set more standards for trail builders. Maximum grade can be a site-specific determination that considers soil type, the presence of solid rock, annual rainfall amount, number and type of trail users and more.
Mountain biking is a relatively new sport, growing popular only in the 80’s and 90’s, and so benefits from modern standards for sustainable construction and maintenance. Recreation Coordinator Jessica Savage, with the Vermont Department of Forests, Parks and Recreation, says, “When we build new trail, we build to the highest level of sustainability.” But why should anyone care about all of this? Jill Van Winkle, Trail Specialist with IMBA, explains: “The two most important reasons are user experience and minimizing impacts to the environment. Good trail guidelines provide land managers, builders, and trail users with the tools to create sustainable trails that provide experiences that meet user expectations.” As for riders, Van Winkle points out that understanding the process helps mountain bikers to be better trail users. “We are more likely to show up for volunteer work days, provide feedback to land managers, and be more aware
of how our riding might affect the trails, like by avoiding riding in muddy conditions or by avoiding skidding.” A common theme when talking to trail specialists and land managers is that they wish trail users knew more about the process, even before shovels hit dirt, and Van Winkle points to all the planning, meetings, regulatory hoops, stakeholder involvement, and more that goes on before trail construction begins. “Knowing what steps are required, the time periods mandated for each step, and when and how the public can be involved is really important, and knowing how much work it is to construct and maintain trails that see heavy use.” Savage adds, “People think it’s no big deal to build trails. You just cut down some trees. But we’re planning, designing, doing it right. A lot more goes into trail building than people realize.”