Determining the Best Dimension of Transversal Drainage for a Forest Road Network by Employing Hydrological Models

Several factors are involved in the destruction of forest roads, and most of them are generated as a result of rainfall runoff which directly threatens the surface of forest roads. To minimize this damage, a well-designed drainage system in accordance with the situation in the region is needed, for which the optimal number and diameter of pipes must be calculated. Mixed broadleaf high-elevation forests in northern Iran. In this study, by employing hydrological models, geographic information systems (GIS), and field survey, we divided the area to 42 sub-areas. We then considered the factors such as hydrologic soil groups, hydrology situation, curve number (CN)