Robert T. Pack
    Civil and Environmental Engineering,
    Utah State University
    Logan, UT 84322-4110
    robert<at symbol>
    David Tarboton
    Civil and Environmental Engineering, Utah Water Research Laboratory,
    Utah State University
    Logan, Ut 84322-4110
    david.tarboton<at symbol>
    Craig N. Goodwin 
    Aquatic, Watershed and Earth Resources 
    Utah State University 
    Logan, Utah 84322-5230 
    Ajay Prasad
    Civil and Environmental Engineering, Utah Water Research Laboratory,
    Utah State University
    Logan, UT 84322-4110
    ajayprsd<at symbol>

    SINMAP 2.0 (Stability Index MAPping) is an ArcGIS 9.x ArcMap Add-in which implements the computation and mapping of a slope stability index based upon geographic information, primarily digital elevation data.  SINMAP has its theoretical basis in the infinite plane slope stability model with wetness (pore pressures) obtained from a topographically based steady state model of hydrology.  Digital elevation model (DEM) methods are used to obtain the necessary input information (slope and specific catchment area). Parameters are allowed to be uncertain following uniform distributions between specified limits.  These may be adjusted (and calibrated) for geographic “calibration regions” based upon soil, vegetation or geologic data.  The methodology includes an interactive visual calibration that adjusts parameters while referring to observed landslides.  The calibration involves adjustment of parameters so that the stability map “captures” a high proportion of observed landslides in regions with low stability index, while minimizing the extent of low stability regions and consequent alienation of terrain to regions where landslides have not been observed.  This calibration is done while simultaneously referring to the stability index map, a specific catchment area and slope plot (of landslide and non landslide points) where lines distinguish the zones categorized into the different stability classes and a table giving summary statistics.

    SINMAP 2.0 is the second major release of SINMAP. The principle purpose of this release is the conversion for use with ArcGIS in place of ArcView 3.x. SINMAP 2.0 is available for Windows operating systems that support ArcGIS for Windows from Environmental Systems Research Institute, Inc. (ESRI).  ArcGIS is used for GIS display functionality. SINMAP 2.0 has been tested with ArcGIS 9.0, 9.1, 9.2, 9.3 and 9.3.1 and requires either ArcView, ArcEditor or ArcInfo licences. SINMAP is partially functional in ArcGIS 10 - see details below. The original version of SINMAP for ArcView 3.x, as well as the MW SINMAP V1.1 version for MapWindow are available. Also, SINMAP source code is available for those who want to implement SINMAP on a different system.


    Copyright (C) 2010 David Tarboton, Utah State University

    This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License version 2, 1991 as published by the Free Software Foundation.

    This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

    The distribution for SINMAP 2.0 for ArcGIS 9.x comprises the following:

    Using SINMAP with ArcGIS 10.x


    Usage Notes and Limitations

    1. Grid File and Path Names: Spaces are not allowed in file names or paths (e.g. "My Documents" has a space, and so will not work). File names must not be longer than 13 characters.
    2. Grid Size: Grids must be smaller than 7000 x 7000 cells.
    3. Grid Spatial Reference/Size: All input grids are assumed to be the same size, shape, and in the same spatial reference. This is sometimes checked by the program, but not consistantly.


    Pack, R. T., D. G. Tarboton, C. N. Goodwin, A. Prasad, (2005), "SINMAP 2. A Stability Index Approach to Terrain Stability Hazard Mapping, technical description and users guide for version 2.0," Utah State University. (Adobe PDF 1355 KB).

    Pack, R. T., D. G. Tarboton and C. N. Goodwin, (2001),"Assessing Terrain Stability in a GIS using SINMAP," in 15th annual GIS conference, GIS 2001, Vancouver, British Columbia, February 19-22. (Adobe PDF 255KB)

    Pack, R. T., D. G. Tarboton and C. N. Goodwin, (1998), "The SINMAP Approach to Terrain Stability Mapping," Paper Submitted to 8th Congress of the International Association of Engineering Geology, Vancouver, British Columbia, Canada 21-25 September 1998. (Adobe PDF 328 KB)

    Pack, R. T., D. G. Tarboton and C. N. Goodwin, (1998), "Terrain Stability Mapping with SINMAP, technical description and users guide for version 1.00," Report Number 4114-0, Terratech Consulting Ltd., Salmon Arm, B.C., Canada. (Adobe PDF 1336 KB).


    The original ArcView SINMAP was developed between Terratech Consulting Ltd, Utah State University and C.N. Goodwin Fluvial System Consulting. with the support of Forest Renewal British Columbia, in collaboration with Canadian Forest Products Ltd., Vancouver, British Columbia. It relies heavily on the coupling of steady state topographic hydrologic models with the infinite plane slope stability model, an approach pioneered by Bill Dietrich and David Montgomery. We acknowledge discussions and assistance from them.

    The ArcGIS version of SINMAP 2.0 was developed with support from the Rocky Mountain Research Station, Forest Service, U.S. Department of Agriculture under joint venture agreement number 03-jv-11222014-050. The views and conclusions expressed are those of the authors and should not be interpreted as representing official policies of any Government or supporting agency.

    The digital elevation model methodology and algorithms have been developed by David Tarboton over several years with support from a variety of sources, but notably the National Science Foundation grant EAR-9318977 for the development of the D-infinity, flow directions approach.


    There is no formal ongoing support for this freely distributed open source software. However, we are interested in feedback. If you find errors, have suggestions, or are interested in any later versions contact:

    Robert T Pack
    Utah State University
    4110 Old Main Hill
    Logan, UT 84322-4110
    email: robert.pack<at symbol>

    David G. Tarboton
    Utah State University
    4110 Old Main Hill
    Logan, UT 84322-4110
    email:  david.tarboton<at symbol>