OF-19-06 Landslide Inventory and Susceptibility Map of Boulder County, Colorado

This CGS study seeks to 1) evaluate and map known and previously unmapped landslide deposits with the aid of new high-resolution light detection and ranging (lidar) data and 2) identify landslide susceptible zones based on slope derived from a 10-m DEM and geology from geologic maps at various scales. Includes a report, a PDF map file, and GIS data. Digital ZIP download. OF-19-06D

From the Report:

The CGS provides geologic hazard susceptibility maps to state and local governments for use in planning processes and mitigation plans. The Landslide Inventory and Susceptibility Map of Boulder County is part of a statewide effort to develop inventory and susceptibility maps for landslide-prone areas in Colorado. Substantial growth and development is taking place in the city of Boulder and the nearby towns in the county, especially near mesas and major drainages. This study evaluates and maps known and previously unmapped landslide deposits with the aid of new high-resolution light detection and ranging (lidar) data and identifies landslide-susceptible zones based on slope derived from a 10-m DEM and geology from geologic maps at various scales.

GIS Disclaimer: This map is intended to be used at 1:24,000 scale. The coverage shows areas that have mapped landslide deposits and areas that are susceptible to the development of landslides. Due to the nature of the geologic maps used and the limitations of the model, areas that are more susceptible to rockfall or debris flow may be included in the coverage of the susceptibility map. The map is not intended to give site-specific information as to the precise area and level of risk. No levels of risk are assigned. It should be used as a tool to evaluate where slope stability issues may occur. Susceptibility does not imply that landslides will occur in susceptible areas. It indicates that landslides have occurred in similar areas and that combination of the geology and slope of the area may be favorable for landslides to form in the future. Proper evaluation by a qualified geotechnical engineer or engineering geologist should be made on a site-specific basis prior to future development or alteration to the ground surface that many impact slope stability. Disclosure of potential landslides should be made to any prospective land buyers.