Awaiting Outdoor Accessibility Standards: Trail Building at Shaverâ€™s Creek
by Donica Conseen and Nikki Montembeault
In July 2007, the United States Access Board issued the Notice of Proposed Rule Making Guidelines for Federal Outdoor Developed Areas, which in 2009 then became the Draft Final Guidelines for Outdoor Developed Areas and were made available for comment until December 2009. While these guidelines have not yet reached their final status they are recommended as best practices, and are designed to encourage entities to address accessibility concerns within the realm of the outdoors. The specific outdoor areas that are covered by the Draft Final Outdoor guidelines include: camping facilities, picnic facilities, viewing areas, outdoor recreation access routes, trailheads, trails, and beach access routes. As it pertains to this article, the guidelines provided the parameters for the design and construction of the Shaver’s Creek trail.
School students utilizing the new accessible trail at Shaver's Creek.
When Brian Sedgwick, Building Services Coordinator for Shaver’s Creek Environmental Center, first heard the National Center on Accessibility (NCA) was offering training last spring in San Antonio, he was thrilled at the opportunity to attend. Sedgwick’s anticipation to attend an NCA training course was sparked by an upcoming project to design a new accessible trail at Shaver’s Creek. The outdoor center at The Pennsylvania State University provides a variety of educational and recreational opportunities ranging from tours, trails, discovery rooms, a boardwalk and gardens. The center conducts programing for children and the community within the Stone Valley Recreation Area in central Pennsylvania. Going into the training Sedgwick was not only hoping to gain insight on how to best approach the project, but also how he could create awareness of the principles of universal design with the project team and among staff. While attending the training Sedgwick learned that there are many factors which affect the accessibility of a trail. Physical elements such as the firmness and stability of the trail surface were discussed, in addition to programmatic elements such as providing tactile elements along the trail. Tactile elements not only enhance the experience offered but provide a more accessible experience to those visitors with low vision or who are blind, visitors with cognitive impairments, and in the spirit of universal design, children at various levels of development. When Sedgwick returned home, he started examining the Shaver’s Creek Environmental Center from an accessibility standpoint in addition to Shaver’s Creek Trail. Recognizing the importance of the principles of universal design, he began to educate both his co-workers and the students he teaches at Penn State on the principles in hopes that they would be put into practice.
Sedgwick and his colleagues wanted to construct an accessible trail that would connect to the existing boardwalk at Shaver’s Creek Environmental Center without “paving the wilderness.” The preliminary planning process revealed, that based on the users of the future trail and existing boardwalk, there was a need for an accessible surface that was firm and stable but also slip resistant. While slip resistance on a trail is not a requirement per the Draft Final Outdoor Guidelines, it is recommended as a best practice in instances where it would be beneficial to a defined user group. With the help of the Center for Dirt and Gravel Road Studies, the project team feels the trail surface has a firm, stable and slip resistant surface that falls within the accessibility guidelines.
The Center for Dirt and Gravel Road Studies established in 2000 and housed under Penn State University’s Thomas D. Larson Pennsylvania Transportation Institute, gave valuable insights on the make up of the surface material. The driving intent of the Center is to teach and implement “Environmentally Sensitive Maintenance (ESM) Practices” to reduce runoff and sediment pollution coming from low-volume transportation corridors such as rural roads and trails.
Installation of accessible trail.
The Shaver’s Creek trail corridor was first graded and the base was prepared to ensure that the running and cross slopes met the technical provisions in the Draft Final Outdoor Guidelines. Once the trail was graded, there were areas where the construction of French mattresses was necessary to ensure proper drainage and water flow. A French mattress is a structure under the trail composed of coarse rock wrapped in fabric (typically a geotextile) through which water can freely pass. Installing French mattresses also provides additional support strength in areas along the trail where needed. The theory behind the use of French mattresses over other methods such as cross-drainage culverts is that they require less maintenance (if any in some cases). They can also be a good alternative to cross pipes. The entire length of the trail then had a Class 2A geotextile placed on top of the prepared base prior to the “Trail Mix” being installed.
The aggregate used for the Shaver’s Creek Trail, currently named “Trail Mix” is designed specifically for the surface of trails. The application of Trail Mix at Shaver’s Creek was the first application of the trail material ever for the Center. Trail Mix is composed of a range of rock sizes from 3/8 inch down to fine material. The combination of rock and fines allows for a greater compaction rate than using just a 3/8 inch stone for example. The exact specification for the Trail Mix installation at Shaver’s Creek was to combine existing aggregates and water with four parts unwashed AASHTO #10 (or B3 sand), four parts AASHTO #8, and one part minus #200 fines (collector fines). The Trail Mix was installed on top of a previously laid Class 2A geotextile at a depth of 6 inches and compacted with a minimum 3-ton vibratory roller.
The Center for Dirt and Gravel Road Studies designed the trail with the help from Sedgwick, who reviewed the design to be sure it met the Draft Final Outdoor Guidelines. Resting intervals were planned to meet the running and cross slope requirements while ensuring the firmness and stability of the material could be maintained after installation. In addition, Sedgwick plans to include elements that utilized the Principles of Universal Design by integrating interpretive elements along the trail that explains the thought process behind the preservation of and/or clearing of certain trees and plants while constructing the trail.
The Shaver’s Creek Trail was completed in May 2010 and has been a huge success with local visitors. Sedgwick estimates more than 800 people from local school programs alone have utilized the new trail in the first season. Expanded programming has also attracted older adults since the average running slope of 5-8 percent (an average running slope for a typical sidewalk is no greater than 5 percent) provides for a leisurely wooded nature walk. The vision for Shaver’s Creek is to be an exemplary environmental education and training center known for quality experiential programs that enable people to learn how to live and interact harmoniously and sustainably with each other and the natural world. The Shaver’s Creek accessible trail helps this vision come to fruition for all visitors by providing a universal outdoor experience.
Site Plan (PDF) provided courtesy of SCEC.
For more information:
Brian J. Sedgwick
SCEC Building Services Coordinator
Shaver's Creek Environmental Center
The Pennsylvania State University
3400 Discovery Road
Petersburg, PA 16669-9317
(814) 863-2000 ext 7520