Technical Bulletin No. 0988: Comparison of Road Surface Erosion Models with Measured Road Surface Erosion Rates

Surface erosion from unpaved roads can adversely affect water quality and aquatic resources. Since direct measurement of surface erosion is difficult and time-consuming, most practitioners use models to estimate erosion based on the characteristics of the road and locale, including width, length, surfacing, traffic, ditch and cutslope condition, climate, and underlying geology. We compare measured road surface erosion and runoff data from nine sites across the United States with erosion calculated using the WEPP, GRAIP, and SEDMODL2 models to test ease of model use, ability to predict absolute value of erosion, and ability to predict relative changes in erosion under different road management conditions.