Permanent and temporary forest bridges are an integral part of achieving environmental Best Management Practices (BMPs)for harvesting operations. Within Virginia Tech's Fishburn Forest five stream crossings have been installed to improve access and to provide a demonstration area for continuing education purposes. Approximately 1 mile of abandoned road was re-opened and improved, and 850 tons of gravel used to form the new running surface. In addition to a number of existing fords, three new culvert crossings and five new bridges were installed. These include a 70ft low-water concrete culvert crossing, a two-span 31 ft wooden stringer bridge, and three different types of stress-laminated bridges. This article provides basic information regarding permit acquisition and environmental considerations for stream crossings. Location, design, and installation procedures for a variety of permanent and temporary forest bridges are presented. Finally, an evaluation of bridge installation costs, including materials, labor, and machinery requirements, are shown for the various permanent and temporary crossing types.
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