Between the 1950s and mid-1990s many forestry roads in B.C. were inadequately
constructed with a lack of or poorly managed drainage, subsequently were incorrectly or not at all deactivated, and now pose landslide hazards and an increased risk to the public and the environment. This study defines and tests a preliminary stability indicator that can be used to screen large areas for the relative debris slide hazard from these legacy roads using two fundamental landslide factors: slope and flow (specific catchment area). Using a 2 m-resolution digital elevation model, the stability indicator was applied to a case study area that had previously been the subject of a terrain stability assessment. The stability
indicator proved to be a good predictor of road hazard ratings at a 15% level of significance. This quantitative approach to identifying road hazards may prove useful for prioritizing terrain stability assessments (TSAs) of areas with legacy roads by land managers and could provide additional insight to professionals for TSAs.