Improvements to Demo II Under Way
In 2007, a 555 foot section of the White Trail north of Tedyuscung was rebuilt as a demonstration project for the Sustainable Trails Initiative and known as Demo II. Professional trail builders from the International Mountain Biking Association Trail Solutions worked for several weeks with dedicated volunteers using mechanized equipment and hand tools to make sustainable a critical segment of trail that runs in a generally unsustainable corridor.
The trail as it existed then was highly eroded and continuing to rapidly erode. It was too wide and destined to widen more. The general rule of trail design is that the slope of the trail should not exceed 10%. This segment of trail averages over 20%. Ordinarily trails located on such slopes are closed and replaced with new trails on more manageable terrain. However, this segment, which constitutes the only upper route from Rex Avenue to the north, traverses an expanse that features no other options. The entire area is steeply sloped from the close-lying private property to the east, to the creek, which is over 100 vertical feet below to the west. So the Demo II trail was rebuilt in place. Trail builders narrowed the trail and added numerous stone terraces, grade reversals, chokes, and other features to provide a stable tread that would shed stormwater.
In the years since the completion of the project, problems have persisted. Although the tread is more stable and not widening quickly, considerable soil has been scoured away by stormwater, which makes the trail more difficult to traverse and incentivizes users to go off-trail. Although many users relish the challenge provided by the large terraces and rock features, others continue to seek ways around these elements, effectively widening the trail and exacerbating erosion. Although FOW makes every effort to get our projects right the first time, we also attempt to learn from our mistakes and act to address them.
Over the next week or so, professional trail builder and Wissahickon trail veteran Steve Thomas of Terra Firma Trails will be working with volunteers to improve Demo II. Specifically, they will reduce the width of widened areas of the trail and add several features: more chokes, drains, and small ramps or other less abrupt lines, which may be adjacent to terraces. In addition, some existing drains will be improved. The result is intended to be a trail segment of similar character, but narrower, with greater long-term stability and more options for users who wish to traverse the segment easily. Those of you who enjoy the current challenges of this segment of the trail may rest assured that most of those challenges will remain with little alteration.
Please be aware of the construction activity on the white trail north of Rex Avenue and proceed with caution. For your own safety and the safety of trail workers, do not attempt to walk, run, or ride past any operating machinery until the operator acknowledges you and signals for you to proceed.
by David Dannenberg, FOW Board Member and Crew Leader