GSDA:Obtaining Soil Type Data from the EPA

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The EPA offers STATSGO soil type data in one large "core data" download. One advantage of the EPA's data is that the land use and soil type data are included together in one download. The steps for obtaining the soil data are outlined below.

First, locate the HUC number for a watershed area from the EPA's Locate Your Watershed website.

Second, go to the EPA BASINS Data HUC Index web site. If the link does not work, follow the bulletted steps below:

  • Go to www.epa.gov.
  • Click on the Information Sources link at the left.
  • Click on the Databases and Software link.
  • Click on the Geographic Information Systems link.
  • Click on the Better Assessment Science Integrating Point and Nonpoint Sources (BASINS) link.
  • Click the Web Download link.
  • Scroll down and choose the http://www.epa.gov/waterscience/ftp/basins/gis_data/huc link, found under the heading "Basins 3 Data from the Web."
  1. Go to the Locate Your Watershed website,
    The website offers four methods of searching for an area's HUC:
    • Search by Map...click on a map of the United States to locate the area
    • Find place...perform a quick search based on a single keyword.
    • Places...use the USGS GNIS website to find an area.
    • Locate by geographic unit...enter the area's zip code, state, county, tribal nation, watershed number or stream name.
    This example will use the Search by Map method,
  2. Click on the Search by Map link,
  3. Click on a state,
  4. Click on the EPA hydrologic unit that covers your watershed,
    Some may need to download more than one EPA hydrologic unit to completely cover an area. If finding it difficult to ascertain which unit covers anwatershed, try using another another search method, such as Find place, for example.
  5. Make a note of the 8-digit USGS Cataloging Unit number located just under the Watershed Profile heading,
    This is the HUC number.
  6. Go to the EPA's HUC Index,
  7. Locate and click on the folder named with your 8-digit HUC,
  8. Click on the file named with the HUC followed by "_core.exe," (Example: 16020203_core.exe) and in the ensuing dialog, save the file to the computer,
    The downloaded file is a self-extracting zip file.
  9. Double click on the saved file to open the "Winzip Self-Extractor" dialog.
  10. Specify a location on the computer to extract, or unzip, the files and then click the Unzip button.

Once you've uncompressed the data file, you should have a new folder made up of the HUC number (e.g., 16020203). Inside of this folder you will find a file named "statsgo.shp." This is the primary soil type shapefile containing the polygon boundaries for the soil types of your area. Scrolling down the list of files, you will also find a file named "statsgoc.dbf." This file contains information on the Hydrologic Soil Group and Surface Textures.

For computing composite Curve Number and/or Runoff Coefficient calculations with WMS, you will need to join the Hydrologic Soil Group field, hydgrp, found in the statsgoc.dbf file to the statsgo.shp file using the spreadsheet template provided below, or a GIS application such as ArcView®.

statsgoImport.xls Template

This template contains a VBA macros designed to open both the statsgo and statsgoc tables into a spreadsheet. Then with a single click, users can join the hydgrp field from the statsgoc table to corresponding records in the statsgo table.

Click here to download the statsgoImport zip file, which contains the template and its readme file.

Be sure to view the readme.txt file for instructions on using the template.


GSDA EPA Soil Type.png