WEPP

[1][2] The model was developed by an interagency team of scientists to replace the Universal Soil Loss Equation (USLE) and has been widely used in the United States and the world.

The WEPP model has been improved continuously since its public delivery in 1995, and is applicable for a variety of areas (e.g., cropland, rangeland, forestry, fisheries, and surface coal mining).

In WEPP watershed applications, multiple hillslopes, channels, and impoundments can be linked together, and runoff and sediment yield from the entire catchment predicted.

These include improved algorithms to simulate the effect of hydraulic structures and impoundments on runoff and sediment delivery,[9] the addition of Penman–Monteith ET algorithms,[10] subsurface converging lateral flow to represent variable source area runoff,[11] improved canopy biomass routines for forested applications,[12] and the incorporation of an alternative, energy-balance-based winter hydrologic routine.

[20] The interfaces can be readily accessed and run through the internet (http://forest.moscowfsl.wsu.edu/fswepp/), and do not require any in-depth understanding of the hydrology, hydraulic and erosion principles embedded in the WEPP model.

Figure 1. Screen capture of the WEPP Windows interface after completion of a 100-year hillslope simulation, showing text and graphical output results.
Figure 2. Screen capture of one of the WEPP web-based interfaces for simple hillslope profile simulations. Inputs for and results from a 30-year model run are shown.
Figure 3. Screen capture of the WEPP web-based GIS interfaces for simple hillslope profile simulations. A small watershed with spatial soil erosion (red and green pixels) and deposition (yellow pixels) is shown.