Submitted to: Forest Service General Technical Reports
Publication Type: Government Publication
Publication Acceptance Date: 4/20/2007
Publication Date: 4/20/2007
Citation: Robichaud, P.R., Elliot, W.J., Pierson, F.B., Hall, D.E., Moffet, C.A., and Ashum, L.E. 2007. Erosion Risk Management Tool (ERMIT) Users Manual (Version 2006.01.18.). General Technical Report RMRS-GTR-188. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fort Collins. 24 p. Interpretive Summary: Runoff and erosion risks increase following fire. The Erosion Risk Management Tool (ERMiT) was developed to predict surface erosion from post-fire hillslopes and to evaluate the potential effectiveness of various erosion mitigation practices. The web-based ERMiT uses Water Erosion Prediction Project (WEPP) technology to estimate erosion, on probabilistic terms, from burned and recovering forest, range, and chaparral lands with or without mitigation treatments. ERMiT generates a distribution of rain event sediment delivery rates with a probability of occurrence in each of 5 years following fire. Output includes event sediment delivery rate distributions for burned hillslopes treated with seeding, straw mulch, and erosion barriers. The model provides a method for land managers to assess risks of damaging runoff and erosion events following fire and to aid management decisions on the location, timing, and approach of mitigation applications.
Technical Abstract: The decision of where, when, and how to apply the most effective post-fire erosion mitigation treatments requires land managers to assess the risk of damaging runoff and erosion events occurring after a fire. To aid in this assessment, the Erosion Risk Management Tool (ERMiT) was developed. This user manual describes the input parameters, input interface, model processing, and output files for version 2006.01.18. ERMiT is a web-based application that uses Water Erosion Prediction Project (WEPP) technology to estimate erosion, in probabilistic terms, on burned and recovering forest, range, and chaparral lands with and without the application of erosion mitigation treatments. User inputs are processed by ERMiT to combine rain event variability with spatial and temporal variabilities of soil burn severity and soil properties, which are then used as WEPP input parameters. Based on 20 to 40 individual WEPP runs, ERMiT produces a distribution of rain event sediment delivery rates with a probability of occurrence for each of five post-fire years. In addition, event sediment delivery rate distributions are generated for post-fire hillslopes that have been treated with seeding, straw mulch, and erosion barriers such as contour-felled logs or straw wattles