ERMit is a web application which models erosion on current or proposed forest road. ERMiT allows users to predict the probability of a given amount of sediment delivery from the base of a hillslope following variable burns on forest, rangeland, and chaparral conditions in each of five years following wildfire. The model also predicts the effectiveness of sediment mitigation methods following a wildfire, such as applying mulch or seeding.
Wildfire changes the landscape dramatically. This altered landscape, with its patches of bare and water-repellent soil, has the capacity to produce large volumes of runoff, and the large amount of sediment it contains poses threats to fish, downstream water users, infrastructure, and private property.
The Erosion Risk Management Tool (ERMiT) is an online FS-WEPP model available to managers for the post-fire environment. Wildfires are episodic and there is often a large erosion response when the precipitation follows. ERMiT provides an estimate of the amount of erosion that may occur after a fire, but it is unique in that it also provides erosion probabilities based on factors like the type of storm that would likely hit area after the fire, variability in soil properties, and soil burn severity.
Another unique feature of ERMiT is that it allows the user to select different erosion control treatments, so they can evaluate what will happen if they choose between various options. ERMiT is now used by the majority of the Forest Service Burned Area Response (BAER) teams (with over 10,000 model runs in 2013) to provide guidance as to what to expect after a fire and the estimated increase in erosion.
Single-storm probability of exceeding a given sediment delivery.
ERMiT version 2014.04.07