ASCE “Civil Engineering”, April 2015, Pages 74-81
By Peter J. Kempf and Jason A. Snyder, P.E., M.ASCE
A significant portion of a scenic byway through a pristine national forest was completely reconstructed and upgraded using a method that recycled 100 percent of the existing roadway, shoulders, and subgrade soils—saving time and money and reducing impacts on the environment.
Pennsylvania State Road 321, which carries the Longhouse National Scenic Byway through Allegheny National Forest, is used not just by outdoor enthusiasts but also by the forestry and gas and oil industries.
NORTHWESTERN Pennsylvania is the home of the commonwealth’s “Wilds” region, which boasts expansive white pine and hemlock forests, pristine rivers and lakes, and a wide variety of wildlife, including elk, beavers, bobcats, bears, otters, turkeys, and white-tailed deer. The Wilds is also home to many of Pennsylvania’s cultural and historical resources, including the Pennsylvania Grand Canyon (Pine Creek Gorge), the Kinzua Dam and Allegheny Reservoir, Cherry Springs State Park, and even Punxsutawney Phil, the famous groundhog believed to have the ability to predict the lengths of winters. Among the region’s landmarks is the Kinzua Viaduct, the longest and tallest railroad bridge in the world at the time of its construction. (Read “Lessons from the Kinzua,” by Thomas G. Leech, P.E., S.E., A.M.ASCE, Jonathan D. McHugh, P.E., A.M.ASCE, and George Dicarlantonio, P.E., Civil Engineering, November 2005, pages 56–61.)
Three state scenic byways are located in the region: the 100 mi Bucktail Trail follows the Old Sinnemahoning Trail; the 27 mi High Plateau passes through Sproul State Forest; and the Kinzua provides access to one of the engineering marvels of the 19th century. On the federal level, the 27 mi Longhouse National Scenic Byway takes travelers deep into the forests of McKean County.