Soils Data Description
Restoration Planning: Soils data are essential to design
of restoration & remediation projects. In addition, erosion risk, reclamation
ease, runoff potential (surface contamination risk), groundwater contamination risk (CEC, permeability, depth to saturated soils), are all
key to prioritizing restoration projects. Hydric soils will help with wetland delineation.
Data Description: The USDA Natural Resources Conservation Service maintains a number of soils databases (including SSURGO
and NASIS). The available soils data likely to be of greatest use in watershed analysis
and planning is at the 1:24000 scale and is available through NRIS along with an ArcView extension called the Soils Data Viewer. This software
interprets soils data and presents the interpretations in reports and maps. Currently, the user must download the soils data and the Soil Data Viewer
and run the interpretations (hardware requirements are explained at the web site). Eventually, some of the maps of interpreted soils data
will appear on NRIS's online mapper.
Location of sample sites/areas assessed: The map of counties with completed
digitized soils data can be seen on the website below. In the upper Clark Fork basin, soils data are
Missoula, Powell, and Granite counties.
Nature of location information in database: The data are georeferenced
and are in the state projection used by NRIS.
Time frame: The soils databases SSURGO and NASIS are still under
development and will be maintained by NRCS.
Parameters measured & methods used: Soil data and interpretations particularly key to watershed analysis
and restoration planning include: erodibility factors, slope, available water capacity,
percent clay, percent organic matter, bulk density, hydraulic conductivity, sodium
absorption ratio, cation exchange capacity, pH, frost free days, septic system suitability, flood frequency, depth to saturated soil, hydric soils,
erosion hazard, reclamation ease, permeability, runoff potential, depth to soil restriction for buildings. Many more parameters are available. See
relevant references for information on methods, etc.
Quality of data: Data collected by soils professionals using
standard soils methods; suitable for use in management.
Relevant references: NASIS info and user's guides at http://nasis.nrcs.usda.gov/
SSURGO user's guide at http://www.ftw.nrcs.usda.gov/ssur_data.html
Soil Data Viewer user's guide at http://www.itc.nrcs.usda.gov/soildataviewer/user_guides.htm
Responsible party contact:
At NRIS, contact: Duane Anderson
Natural Resource Information System, Montana State Library.
1515 E. 6th Avenue, Helena, MT, 59620-1800
At NRCS: Tom Potter, 406- 587-6968
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