Why do we need an engineer? Crafting trails that last

The average trail user probably takes the grade, structure, and views for granted while hiking, biking, or snowshoeing, but engineers work behind the scenes to make sure your moments on the trail are safe and smartly designed. Good trails need to withstand a 10-ton emergency vehicle while also making your back-to-nature treks beautiful, and Lauren Fay Carlson finds out how one local trail does both.
When you think of a trail, you likely picture your destination, or workout, perhaps the trees, or the wind blowing through your hair when you reach top speed on your bike or roller blades. You may consider if the trail is smooth or bumpy, if the elevation is difficult, or if you met your timed goal if the wind was on your side.
Whether you're a frequent or rare trail user, you may have never considered the actual engineering that was involved in the project or the special considerations given to each unique trail. Though not all trails are specially engineered, the best ones usually are, creating paths that last for decades by tackling each project with care and often adding time-tested elements that exist just below the surface.

"A bike path is like a mini road," says Scott Post, engineer at Prein & Newhof, a civil and environmental engineering firm that specializes in outdoor spaces. Though many may not think a trail requires the same effort as a road that carries cars and trucks, the traffic brought on by bicyclists and walkers can have much of the same effect, and thus require many of the same considerations as an auto-centric road. Most trails are also required to withstand the weight of a 10-ton emergency vehicle, should a trail user require medical assistance on the path.

Considering weight requirements and overall usage, the stability of a trail is vitally important. Especially in Michigan, where clay-rich soil abounds, Post must consider the ground material onto which a trail will be built. Sometimes this means pouring feet of sand and utilizing a special fabric to provide a solid surface. With Michigan's wide variety of lakes, rivers and streams, Post must also consider surrounding water tables and heavy rains. "One of the biggest engineering challenges is drainage," says Post. "Not every spot is the same," he adds, and notes that each trail must be approached differently.

And these are just the elements considered for relatively simple, flat trails. Trails that vary widely in elevation, those that cross bodies of water, those that must travel beneath a road's surface and those requiring a bridge complicate matters even more. "The necessity of an engineer is obvious when you look at a bridge or tunnel," says Post, who has worked on numerous trail projects with these complex issues.
One of the projects requiring special attention is the Fred Meijer Grand River Valley Trail, which runs through Ionia with a trailhead at W. Main St. near Whispering Creek Dr. With a non-motorized, 80-ft. bridge that will cross over M-66, bikers and walkers alike will be able to continue the trail's path with ease in a safe environment.
"Getting across M-66 was actually a huge challenge," says Post, who worked to develop a practical, eye-catching solution that required community buy-in as well as secure funding from both MDOT and the city of Ionia itself. Nearing completion in the fall of this year, Post notes that the bridge will "be a signature piece in downtown Ionia."

In addition to jumping the M-66 hurdle, Post and company also tackled the trail's crossing of the Grand River five times. In order to maintain the history of the trail, the engineers and landscape architects who worked on the project maintained the old railroad trestles that crossed the river--and worked this theme throughout the trail's aesthetics. Post notes that landscape architects are an important piece of the puzzle -- and often necessary to create a memorable user experience. James Morgan of RJM Design, the landscape architecture firm hired for the project, assisted in creating a unified look for this section of the trail, including working in the old trestles and creating signs for the path that mimic old railroad signage.

While Morgan says his firm works mostly on land planning projects, he was happy to tackle a trail. "Really what we love to do is create outdoor spaces for people," he says. In turn, Morgan notes the importance of trail engineering for the longevity of an outdoor space that he has worked to make a respite for its users. "The important part is what you don't see," he says.
Most of all, Morgan, who has worked with Post on multiple projects, notes the value of teamwork between civil engineers and landscape architects to create a stable, polished trail. "It's been a great relationship," he says.

Next time you're out on the trail, consider the careful engineering that went into the project. Whether crossing a river or traversing a tunnel, try to imagine the surveying, planning and preparation that went into creating a stable pathway and, if you stop at a particularly beautiful trailhead, the artful design of the trail's aesthetics. "There's a distinct advantage to having an engineer," says Post, who aims to create trails that last for decades.

This article is part of an ongoing series, Moments on the Trails, and was made possible by the West Michigan Trails & Greenways Coalition. For more information about the WMTGC, visit wmtrails.org.

Lauren Fay Carlson is a freelance writer and editor, Aquinas alumna, and Grand Rapids native. Her work can be found at www.emptyframecreative.com, and she can be reached at [email protected] for story tips and feedback.

Photography by Adam Bird
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