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Construction Projects

Learn how to build new trail structures so you can practice your skills on trail with WTA.

Building brand new structures and trails is one of the most fulfilling kinds of trail work. From nothing, you construct a feature that will connect hikers to wild places for years to come. Following are some different kinds of trail structures you might create on trail with WTA.

Building New Trail

Example of preliminary new trail construction at Grand Ridge. Photo by Mike Hardy.

Pioneering a new trail is no doubt one of the most rewarding types of trail work. Foot by foot, you create with your own hands a corridor through the forest that will grant hikers access to previously unknown natural spaces.

Before volunteers arrive on the scene, land managers survey the area and map out where the trail will go so that when you get to a work party, the course is all ready for you to dig in. In the picture to the right, volunteers break ground on a new section of trail. 

To Build a New Trail

  1. Brush: clear the travel corridor by lopping, sawing or digging out brush that blocks the 2 to 4 foot tread width and 8 foot clearing limit of the trail. Dig out organic material too.Example of finished new trail at Cougar Mountain. Photo by Mike Hardy.
  2. Excavate: especially on steep hillsides, dig out the flat shelf of the trail into a full bench cut so that the entire width of the trail is on flat terrain. Shape the backslope (uphill side of the trail) into a 45 degree angle and remove any material that might fall onto the trail.
  3. Finish: use a shovel or grub hoe to overturn the mineral soil and smooth the tread into a walkable surface, making sure that the trail is slightly outsloped. Pack tread down.

Building Rock Walls

A finished rock wall at Glacier Basin. Photo by Lynn Kittridge.

Under the footsteps of hundreds of hikers, trails erode relatively quickly, especially when they’re built on steep slopes. When slough begins to fall down onto the trail, hikers avoid it by walking on the outside edge of the trail, which drags the trail downhill. Under such circumstances, retaining walls built below the outside edge of the trail can help prop it up as seen in the picture to the right. 

Retaining walls can be built out of both wood and rock. Wood retaining walls (called crib walls) are easier to build, but rock walls are sturdier and are often the best option.

To Build a Rockwall

  1. Excavate a full bench cut in the hillside below the tread, insloping the foundation slightly.
  2. Use a rock carrier to place large rocks, as flat as possible, along the width of the foundation so that they angle in with the inslope. Make sure that they lay sturdily before proceeding.
  3. Continue to lay rocks on top of the bottom tier in a brick-work pattern up to the tread, ensuring that rocks are placed securely. Fill holes with smaller rocks and gravel.

Building Turnpikes

Volunteers build a turnpike at Indian Heaven. Photo by Ginger Sarver.

If you've hiked much in the Northwest, you've probably encountered a mud-hole or two. In boggy areas where water absolutely can’t be diverted by a simple drain dip, turnpikes are sometimes necessary. A turnpike is an elevated walkway constructed of two parallel logs or rock walls filled in with rock and mineral soil as seen on the right.

To Build a Turnpike

  1. Scrape out mucky area.
  2. Dig two parallel trenches and place peeled logs in them, securing them with stakes or rebar.
  3. Fill space between the logs with large rocks at the bottom and smaller gravel and mineral soil at the top, forming a crown higher than the logs so water can easily drain off.

      Building Bridges and Puncheons

      Example of a puncheon at Grand Ridge. Photo by Dick Axon.

      When a trail crosses a river or boggy area, there is no way around it but to build a bridge. Luckily, building a structure as tangible as a bridge is also extremely satisfying. Some examples of WTA-built bridges can be seen on the right. 

      Especially in the backcountry, bridges are often made of native timber from trees surrounding the construction site. There are a number of different kinds of bridges that are built for varying purposes.

      Parts of a Bridge

      Volunteers built a foot log bridge at Lone Fir. Photo by Joe Hofbeck.

      • Stringers: long beams that run the length of the bridge and hold up the travel surface.
      • Sills: logs on either end of the bridge, perpendicular to stringers, that stringers rest on.
      • Decking: flat planks on top of the stringers that form the travel surface of the bridge.

      Types of Bridges

      • Puncheons: boardwalk-like structures, low to the ground, built in boggy areas.
      • Foot logs: single-stringer logs, flattened on top, built on foot-traffic only trails.
      • Multi-stringer bridges: wider bridges built with more than one stringer to accommodate stock or cyclists. Often higher above the water, with hand rails.