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The current Spokane County Soil Survey began in 1998. Since that time, there have been many changes, most notably in the technology available to the soil survey crew. The crew is committed to embracing available technologies in an effort to provide the end-users with a superior product.

Traditionally, soil surveys have been done on aerial photographs. The survey was viewed using a matching pair of aerial photos and special stereo lenses. This method is being replaced by Digital Orthophoto Quandrangle, or DOQ. A DOQ is a computer generated image of an aerial photograph. A particular benefit of DOQ is the ability to remove the image displacement caused by terrain relief and camera tilts and blend the characteristics of a photograph and a map.

The Spokane County Soil Survey crew is using DOQs, DRGs (topographic maps), CIRs (color infrared photos), precipitation maps, geology maps and the tools available in ArcGIS to layer and evaluate patterns across the landscape. This allows the crew to create a very accurate pre-map for use in the field. Areas that will require a more in-depth investigation can be identified prior to beginning the field work. And, once mapping is completed for the entire county, the same data layers and tools can be used to evaluate the quality and consistent application of soil line placement and interpretation assignment.

Geospatial Layers
Aerial Photography	Color Photography
Topographic Map	Old Survey

The soil survey crew has certainly entered the computer age and is enjoying the benefits of modern technology. From ArcGIS to GPS units, their work is becoming more consistent, easier to evaluate and track, and more efficient. But even with all the technological advances, there is still the need to dig holes and get dirty - something no soil scientists wants to change.

The soil survey in Spokane County has been a model of the benefits of technology to field soil scientist. It has also been a remarkable partnership. The Spokane County Conservation District and Spokane County have partnered with NRCS to complete the updated soil survey for Spokane County. The Spokane County Conservation District went before the Spokane County Commissioners to ask for a special assessment to help fund the Soil Survey. Currently, they provide three soil scientists to the staff of five. The soil survey will be complete in 2007, 39 years after the last soil survey was published.

Please send all comments and questions to scott.bare@wa.usda.gov, Soil Survey MLRA Project Leader.

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