National road erosion and mass wasting risk data for large scale planning and local implementation

Photo Credit

Forest Service photo

A National Forest road in Idaho from the archives of a road survey done in 2010.

Roads are the largest constructed infrastructure asset in the Forest Service. They also make up the longest road system managed by a single agency in the country. Researchers recently created the first dataset showing erosion impacts across all Forest Service roads.

Wouldn’t it be nice if you could look at a map of the country and see watershed-scale risks from roads, then zoom in to see how those risks are distributed across the region or forest? What if you could then zoom into a watershed of interest that has particularly high risks and view the road segments that contribute the most risk to that watershed, so that you could find solutions? What if you were also interested in many places across the country that have few if any roads, but may need access for management, and you wanted to know whether there were safe places to build roads within them?

A new GIS dataset seeks to answer these questions and provides comprehensive, nationally consistent road segment, stream reach, and Digital Elevation Model grid scale information on road erosion and slope stability risk for roads. The dataset includes summaries at 6th-code watersheds that can be viewed and interpreted at regional to national scales, while allowing analysts to zoom into small portions to isolate and identify potential challenges and solutions.

These data allow managers to rapidly assess current watershed conditions and evaluate road effects within the watersheds that will be affected by proposed fuel treatments. Currently, the datasets are saving many hours of work by watershed specialists working in Oregon, Washington, and California to support fuel treatment projects. 

The dataset was also used to rapidly and consistently evaluate context of existing road effects on watersheds and slope stability risks across the nation for the recent roadless area Environmental Impact Study (EIS). Without these data, the analysis of existing road erosion context and stability risk would have been an enormous and slow new project to successfully evaluate watershed impacts from changes to the roadless rule.