The University of br/itish Columbia


Debris flows are a type of landslide activity that commonly occur on steep mountainous terrain. UBCDFLOW is a model that may be used to evaluate the likely travel distance of a debris flow. Travel distance is an important component of any landslide risk analysis.

UBCDFLOW is intended primarily to assist the user better understand factors influencing the travel distance of debris flows. Accordingly, it is a decision-support tool, intended to supplement judgement and experience. For an assumed initial failure volume, changes in event magnitude arising from volumetric entrainment and deposition along the downslope path of movement are used to establish total travel distance. Equations on which the model is based are reported, together with a glossary of terms, and a list of published references on development and application of the model.

Blueberry Creek debris flow
Blueberry Creek debris flow, 17 km southwest of Castlegar, British Columbia

The UBCDFLOW user guide describes how to run a simulation, and includes a tutorial exercise for illustrative purposes. The UBCDFLOW model is launched from this site.

UBDFLOW was developed using field survey data from debris flow activity on the Queen Charlotte Islands, British Columbia, using an empirical-statistical approach. Accordingly, it should only be used where the terrain is similar and where its suitability can be demonstrated through experience.