Landslides/Land use

Step Wise Guide

Erosion

· Can land use activities increase natural landslide and debris flow risk?

Refer to the "Warning" button in the tool interface. Follow up any remote sensing work, including using NetMap, with field work to verify environmental conditions and landslide and debris flow risk. There is never zero risk, there is only degrees of risk, which often is best considered on a relative basis.

Landscapes with no land use activities can have significant natural landslide risk, including areas of old growth forest. However, land use activities related to mining, timber harvest, road construction, reservoir development and fire can accelerate landslide risk. Detailed information about the history of land use and the history of landsliding, in the context of natural landslide risk, is required to understand how land use activities can increase landslide risk; refer to the sections on landslide and debris flow parameters and the bibliography for additional information.

NetMap’s attributes that address landslide and debris flow susceptibility based on topographic controls can be used as a first order approximation where one might expect land use to increase susceptibility. Refer to the “Attention” button in erosion tool interfaces

Step 1: Go to NetMap Erosion Tools > Generic Erosion Potential. Display the GEP grid including the “delivered” GEP attribute.

Step 2: Go To NetMap Erosion Tools > Shallow Landslide Potential. Display the Shallow Landslide grid including the “delivered” attribute.

Step 3: Go To Channelized Mass Wasting > Debris Flows. Display the “debris flow susceptibility-reaches” or “debris flow susceptibility-junctions” data to examine the spatial variation in potential (provisional) debris flow susceptibility across your watershed or landscape. Read thoroughly the Technical Help Guide on the various slope stability attributes, including debris flows. Follow up any remote sensing work, including using NetMap, with field work to verify environmental conditions and landslide and debris flow risk. There is never zero risk, there is only degrees of risk, which often is best considered on a relative basis.