These web services can be used to retrieve both spatial and non-spatial data in applications that support the Open GIS Consortium WMS, WFS standard, or ESRI ArcIMS services.
Announcements
All web services will be unavailable for some time on October 28, 2008 for hardware upgrades.
If you use these soils services, you should be migrating your requests to the "Soil Data Access" services hosted at http://sdmdataaccess.nrcs.usda.gov. All Soils services hosted at this site will be shut down at some point.
Availability
The web services will be unavailable nightly between 23:30 and 05:00 MST and on Sundays.
They may also be unavailable on Tuesdays and Thursdays between 17:00 and 21:00 MST for scheduled maintenance and software updates.
Web Services
| Name | Type | OGC Support | Description |
|---|---|---|---|
| Soils | Image | -- | SSURGO mapunits and status map |
| Soils_feat | Feature | WFS | SSURGO mapunits and status map |
| Soils_Agg_Attr | Image | WMS | SSURGO mapunits with aggregated attributes and status map |
| Soils_Agg_Attr_feat | Feature | WFS | SSURGO mapunits with aggregated attributes and status map |
| Admin_Areas | Image | -- | US political boundaries |
| Common_Resource_Areas | Image | WMS | Common Resource Area boundaries |
| USDA_Offices | Image | -- | USDA Office points |
| USDA_Offices_feat | Feature | -- | USDA Office points |
| USDA_Service_Centers | Image | WMS | USDA Service Center points |
Help
How to use WFS services
Web Feature Services return geographic features and attributes that meet the requested parameters. The return format is typically GML, an XML grammar that can contain feature coordinates and attributes.
Each WFS service supports at least three methods. The GetCapabilities method describes the features supported by the service; it tells you what you can do with it.
The DescribeFeatureType method describes each accessible data layer in detail, such as the geometry type, column names, data types, etc.
To actually get the feature and coordinate data, you use the GetFeature method. It returns the coordinates and attributes that meet your filter criteria (arguments).
See a working demo of the Soils_Agg_Attr_feat WFS.
How to use WMS services
Web Map Services return map images in common image formats such as JPEG, GIF, PNG, and others. WMS services have three methods of primary interest. Just like WFS, WMS services support requests for GetCapabilities which describes what you can do with the service. It also returns metadata about the service.
The GetFeatureInfo method is used to return attribute information for the feature at the query location. It is used by applications to implement the Identify feature.
The GetMap method returns the actual map image. This method can optionally support a variety of user options such as reprojection, image formats, etc. However, since these are optional and implementations vary, first check the GetCapabilities method to see what a given service actually supports.
See a working demo of the Soils_Agg_Attr WMS.
For more information, see OGC's WMS 1.1.1 specification.
How to use in ArcGIS
The web services have been tested successfully with ArcGIS Desktop versions 9.2, 9.1, 9.0, and 8.3 and also ArcExplorer Java Edition 4 and 9.
For instructions, see your application's built-in help contents. In ArcMap 8, type "Internet Servers" in the Help Index. In ArcExplorer, type "World Wide Web" in the Index.
For the "URL of server", type http://sdmws.nrcs.usda.gov
For additional help, call Johan Alfredeen at (970) 295-5586.
Note: For help on the Soil Data Mart (http://soildatamart.nrcs.usda.gov), please email SoilDataMart@nrcs.usda.gov