Erosion Prediction with RUSLE2

Caltrans RUSLE2 Software

The Revised Universal Soil Loss Equation, version 2 (RUSLE2) is an advanced, user-friendly software model that predicts long-term, average annual erosion by rainfall. Modified as “Caltrans RUSLE2,” this software is streamlined for use on large, roadway construction projects and includes commonly used Best Management Practices (BMPs).

This version of Caltrans RUSLE2 (August, 2011) includes:

  • BMP management options and folder titles are more intuitive for the user.
  • Compost Erosion Control Blankets (CECBs).
  • 24-inch diameter fiber rolls (permanent).
  • Earthworks (cut, fill, track walking) associated with all construction activities have been improved.
  • All pre-existing and post-construction vegetation have been modeled to California native growth patterns, with summer dormancy for annual grasses.
  • Compatibility with the current RUSLE2 version (2011) developed by the USDA/ARS and NRCS.
  • Effectiveness of all RECBs and mulch materials have been calibrated to two independent studies conducted in Texas and San Diego, California.
  • Effectiveness of all permeable barriers is based on more realistic stormwater and surface water flow conditions.


Whereas every effort has been made to incorporate accurate data into the Caltrans RUSLE2 software and databases, its empirical nature can only suggest annual averages of erosion and not exact amounts of sediment into receiving waters. Please verify all Caltrans RUSLE2 results using best professional judgment. Caltrans does not guarantee that use of the Caltrans RUSLE2 software will assure regulatory compliance in all situations.

Erosion Prediction Procedure

The Erosion Prediction Procedure (EPP) defines a method to predict erosion rates at construction sites. The EPP includes a series of steps to properly characterize project sites and facilitate more accurate evaluation of the anticipated erosion and the effectiveness of proposed soil stabilization and sediment control practices. The procedure introduces the concept of a Maximum Allowable Erosion Rate (MAER) for the construction and post-construction phases to establish a performance goal for comparing calculated erosion rates.

Caltrans RUSLE2 Training

This eight-hour, advanced course presents RUSLE2 modified for Caltrans use as a tool for predicting surface erosion and selecting temporary and permanent BMPs. It covers requirements in the new Construction General Permit (CGP) for Risk Level Determination (RLD) and NOT/NOCC related to RUSLE2. This class is listed in LMS as “Design-Erosion Prediction using RUSLE2”, Course Code 100504.

A 2-hour webinar was presented on August 18, 2011 focused on advanced Caltrans RUSLE2 topics that built upon the content taught in the Caltrans RUSLE2 training course (Predicting Erosion and Selecting BMPs using RUSLE2).  Topics included combining BMP treatments and altering slope topography. 

Download Slide Presentation (PDF)

Launch Digital Recording of Webinar

Download Quick Start Guide for Incorporate Compost (DOCX)

Download Advanced Topics Webinar Questions & Answers (PDF)

Users of the Caltrans version of RUSLE2 may find these guides, worksheets and frequently asked questions helpful. Included below are guides, worksheets, and answers to frequently asked questions.