This method estimates basic erosion hazard zones adjacent to arroyos based on channel width and depth and meander belt width. The method was designed by the City of Austin, Texas, and contains two levels of assessment, a simple and conservative level, and a more detailed level when the first level results are determined to be too conservative.
The delineated Erosion Hazard Zone covers the surface an subsurface, and is based on potential future channel incision and accounts for channel migration within the active meander belt.
Further vertical incision and lateral migration extents are estimated through a basic equation relating those distances to bankfull width and depth and the width of the channel meander belt.
City of Austin Watershed Protection Department, 2013. Guidance on Establishing an Erosion Hazard Zone. Austin, TX.
Note that graphic above was taken from this publication.