Friday, July 1, 2011

How a Trail is Built

Volunteering for a trail project provides hikers with additional or improved trails to traverse into America's magnificent wilderness areas, and these volunteer projects also reward the volunteers with pride and a sense of having contributed important work to the hiking community.  With the budget cuts inflicted upon national parks and national forests over the last several decades, much needed trail work would go undone without volunteer assistance.


Here's how a new trail is created...

First, the trail designer “flags” the proposed route (note orange flagging on bushes in center of photo)...




Small standing trees and bushes that are in the trail corridor are cut down (large trees are generally avoided by routing the trail around them)...



Next the trail corridor is cleared of fallen branches, underbrush, rocks, etc., a procedure called "swamping the corridor"...




 ...including the removal of fallen trees...




...regardless of their size.  Trees of large circumference as the one below require 3 cuts -- which creates 2 cutoffs -- which can be individually rolled off the trail corridor, because one large cutoff would be too difficult to move by hand...




Leaning trees often require several cuts to remove them from the corridor...


Rocks that are buried in the trail tread are removed with a long, sturdy, metal pry bar, also called a rock bar...



 Stubborn buried boulders are dug up and removed when possible, sometimes requiring many hours of labor...




Each volunteer takes a 20 foot section, creates the new trail tread, then jumps ahead to a new section...



 ...but always keeping a safety zone between workers because trail tools are sharp and dangerous.



A steep mountain slope requires a deep cut into the hillside and the removal of much dirt (the orange vests and caps were required because it was hunting season)...




A “finishing” crew assures the trail is smooth with only mineral material remaining (with no vegetation growing in the trail corridor.)





Really steep inclines can require switchbacks...





 ...or wooden steps...




...or stone stairways...



 The steps might even be quite elaborate like these we built in Cape Cod National Seashore...






Trail sections that are prone to getting wet will  erode quickly, so a raised “turnpike” may be needed with drainage along each side...




...and sometimes you have to divert the water to the other side of the trail for drainage...




...or a bridge may be constructed if the trail is crossing a creek or a wetland area...



The bridge might be rather simple, as this one in South Carolina’s Francis Marion National Forest...



... or more involved as this 31' bridge we built up at 9,000 feet in Utah's Manti-LaSal National Forest...




A simple solution to a short section of wet trail is called a corduroy, simply laying branches transversely across the trail in the wet area as seen below. Though neither an elegant nor permanent solution, it will suffice for a while, make the area safer to traverse, and prevent further erosion of the trail until further remediation can be effected...





A very unusual project was rebuilding this trail in Maine's Acadia National Park near the Atlantic coastline.  Over a number of years, several hurricanes had deluged the trail, washing it away, so we dug a drainage ditch alongside it (removing boulders and roots)...



...and we also "mined" the surrounding hillsides for large rocks and boulders which we “flew down” to the trail with a high-line grip hoist (pulley system)...




 ...which we then sledge-hammered into small rocks, creating a rock base to prevent the trail from being washed away again...



Finally, we covered the rock base with dirt, creating a beautiful and immovable, erosion-proof trail surface...



So the next time you hike a trail, I hope you'll take a look at its construction and perhaps appreciate the time and effort and thought that went into its construction.  And if you really feel moved, sign up for a volunteer trail project through the American Hiking Society.

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