Forest Road Sediment Production and its Implications

Preventing forest road erosion requires an in-depth understanding of how road design, construction, weather, maintenance and deactivation affect sediment production. Four road components that are potential problem areas are: road surfaces, fillslopes, cutslopes, and roadside ditches. In order to assess and compare origins of sediment production and the effectiveness of each proposed treatment, GIS is used to analyze sediment production from forests roads and its impact on streams. In order to evaluate terrain stability, a SINMAP method is used to calculate the relative wetness of the site based on input including: slope, area, and parameters of steady state hydrology. To prevent fillslope erosion, the treatments in order of increasing effectiveness include: straw with asphalt tack, straw with a net or mat, straw alone, erosion control mats, wood chips or rock, and hydromulch. Similar treatments were applied to cutslopes with the exception of those too difficult to apply to the typically steeper gradients. Road surfaces were treated with layers of crushed rock which proved to mitigate the effects of surface erosion. Roadside ditches were also treated with surfacing in an attempt to either reduce the velocity of runoff water or cover the ditch bottoms thus preventing scouring. Ultimately, the prevention of sediment production, erosion and negative effects on slope stability and stream contamination requires proper planning, design and research by the Forest Professional.Forestry, Faculty ofUnreviewedUndergraduat