The concept and application of best management practices (BMPs) for low-volume roads projects were studied. BMPs are techniques or design practices that will prevent or reduce nonpoint pollution, maintain water quality, and help produce well-built roads. A Low-Volume Roads Engineering Best Management Practices Field Guide was developed to address those key practices. Roads that are not well planned or located, not properly designed or constructed, not well drained, not well maintained, or not made with durable materials often produce negative impacts, most of which are preventable with good engineering and road management practices. A number of key practices and design techniques can be used to prevent adverse impacts on roads. First a road must serve the needs of the user through good transportation system planning. Long-term cost-effectiveness and minimized impacts are then achieved through application of good design and maintenance practices, including a road location that avoids problematic areas such as slides or springs; positive surface drainage; adequately sized and appropriate drainage crossing structures; stable cut and fill slopes; use of erosion control measures; roadway surface stabilization; and materials source development with subsequent site reclamation.

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Today’s geosynthetic products have many useful, creative, and cost-effective applications for rural, low-volume roads. In the management of almost a half-million km (quarter-million mi) of low-volume roads, the U.S. Department of Agriculture, Forest Service (USFS), has developed and adopted many uses for geosynthetics. An overview is presented of many of those uses and their advantages. The USFS gained much of its experience and practice with geosynthetics while constructing a wide variety of Mechanically Stabilized Earth (MSE) retaining walls, including geotextile, timber, modular-block, and tire-faced structures, and reinforced soil slopes. More recently, the USFS has used geosynthetics for MSE bridge abutments and Deep Patch road-shoulder reinforcement. Other typical geosynthetic applications include filtration, drainage, subgrade reinforcement, and erosion control.

A forest roads manual is being written to aid the Brazilian Forest Service in its tropical forestry operations and timber sale concessions in the Amazon basin. The objective of the manual is to develop standards, guidelines, and operational information that will help forest road operations meet best management practices. The manual includes information on transportation planning in conjunction with strategic and tactical timber sale planning; road design; road drainage considerations; roadway materials use; slope stabilization issues; road maintenance issues; and environmental issues, including water quality protection, erosion control, and pollution management. Discussion of each of these typical transportation system planning and design issues considers the unique circumstances and resources found in the Amazon basin. This project grew from the involvement of the Office of International Programs, U.S. Department of Agriculture Forest Service, and the newly created Brazilian Forest Service in the process of helping the new agency manage its large long-term logging concessions throughout the Amazon basin through use of prudent, sustainable management practices. Forest road design and operation are significant parts of overall forest management and major cost items. The manual development is based on many training courses that have been held over the past 10 years across the Amazon basin in the states of Pará, Acre, and Rondonia. In addition, many courses have been conducted and lessons learned in portions of the upper Amazon basin of Bolivia, Ecuador, and Peru. This paper discusses the development of the Amazon Basin Forest Roads Manual and presents an overview of its content as well as many of the unique aspects of building roads in Amazon basin forests.

Geosynthetic-reinforced soil (GRS) bridge abutments have been used on a number of bridge projects over the past decade. This adaptation of reinforced soil technology to bridge structures and their approach fills offers an excellent opportunity to simplify construction, reduce construction time, and reduce cost on structures for which this technology is appropriate. This design concept, in which the actual bridge superstructure rests upon the GRS abutment wall, minimizes differential settlement and eliminates the problematic “bridge bump” found on many structures. The technology has been adapted to both road and trail bridges. The basic design concept of GRS used in bridge abutment applications was evaluated, along with its advantages and disadvantages. Some selected case histories of GRS bridge abutments on low-volume roads and trails in Alaska and California were considered. In addition, the Mammoth bridges, in the mountains of northern California, with high design snow loads and high horizontal peak ground accelerations, afforded an opportunity to design, construct, and monitor GRS-supported spread-footing abutments under difficult service conditions.