Rangeland Hydrology and Erosion Model (RHEM) Services

RHEM is a process‐based erosion model that provides quantitative estimates for runoff and erosion rates specific to rangelands. RHEM represents a modified and improved version of the WEPP model code specific for rangeland application and based on fundamentals of infiltration, hydrology, plant science, hydraulics, and erosion mechanics. RHEM estimates runoff, erosion, and sediment delivery rates and volumes for complex hillslope shapes and slope lengths for single homogeneous rangeland units [e.g., one Ecological Site (ES)]. RHEM is an ongoing coordinated effort between ARS and NRCS.

The RHEM model structure includes equations for water infiltration, runoff, sediment load, splash erosion, thin-sheet erosion, and concentrated flow erosion. Model parameters include soil, slope, vegetation type, canopy and ground cover, and precipitation characteristics.