"Flying" One Ton of Rock in Muir Woods

By Ben Mertz
Trails Stewardship Management Intern

“Tension!” I yell, breaking the serenity in the gully above Muir Woods.

A few seconds later, “Tension!” is the reply from the other side, and I start tensioning the high-line, a cable and pulley system that carries drain rock, gravel, and dirt  across a steep ravine, saving the trail crews time and energy.

The loads are placed in a bucket the size of a wheelbarrow, and then pulled across on a rope, bypassing a section of trail too narrow for power carriers (motorized wheelbarrows). When a bucket is in transit, the cable needs to be tense so it can be pulled (by hand) across. And then when unloading, the cable needs to be slackened so the load isn’t hanging 10 feet above the trail.

“Flying” hundreds of pounds of rock requires focus and concentration, which is why the crews place communication and safety as the top priorities. This means that before any action, the crews call and echo commands. Working the high-line can get repetitive and tiring, but the rewards quickly add up. In one hour we haul a ton of drain rock across the gully.

The temporary high-line is just part of an extensive, multi-year effort to reconstruct the Hillside Trail at Muir Woods. This trail offers great views looking down into the Redwood Creek Watershed, and offers many people an alternative from the crowded boardwalks below.

But the trail needs to be rebuilt to accommodate the heavy foot traffic and steep, erosion-prone slopes, and to protect the sensitive habitat it runs through. The work is done almost entirely during the winter, when the endangered spotted owls won’t be disturbed by the loud machinery and the park is less crowded.

Currently, trail crews led by Kyle Mackiewicz and Larry Evans are hard at work, installing new bridges and retaining walls. Previously, seasonal streams along the slope ran through culverts to pass under the trail, burying the natural stream. The trail crews have now removed this buried material, restoring the streams to their natural setting (and creating a few beautiful cascades in the process).

The new retaining wall sections widen and level the trail, creating a safer pathway and limiting further soil erosion. Less erosion will help keep Redwood Creek’s sediment levels low, improving the coho salmon and steelhead trout habitat.

The narrow winter window for working at Muir Woods means a lot of preparation work must occur beforehand. Volunteers played a crucial role in moving—by hand—drain rock, support beams, decking, and more from staging areas to the project.

The crews are planning to have everything done before February 16, 2013, when bird nesting season resumes and the owls get ready for their young. After that date, all work must be done by hand to protect the quiet soundscape needed for spotted owls.