Development and Implementation of the Idaho Highway Slope Instability and Management System (HiSIMS) Report uri icon



  • Following initiatives and recommendations from the Federal Highway Administration (FHWA), a number of state highway departments over the last 12 years have developed and implemented rockfall hazard management programs for highways. The primary goal is to improve highway safety, but reductions in maintenance and detour costs also result when slope hazards are mitigated. Additionally, a systematic method for agencies to identify and prioritize slope hazard sites allows for highway funds to be allocated efficiently for construction projects or counter-measures to deal with the recognized hazards. Some state highway departments have expanded the original focus on rockfall hazards to also include other types of unstable slope activity, such as landslides, debris flows, and accelerated erosion. A systematic highway slope hazard assessment protocol has been developed for the State of Idaho, which consists of a two-step procedure for hazard ratings: 1) a survey rating by maintenance personnel to classify pertinent slope segments as having a very high, high, or moderate potential of rockfall or erosional debris on the roadway; and 2) a detailed slope hazard rating based on extensive modifications of the FHWA Rockfall Hazard Rating System. The Idaho Transportation Department slope hazard management system has been developed for its centralized, intranet web server that will allow real-time operations from multiple users within the transportation agency. This intranet web-based system is known as Idaho HiSIMS (Highway Slope Instability Management System). 

publication date

  • June 2003



  • slope stability, highway slopes, rockfall, slope hazards, slope erosion 


report identifier

  • Research Contract No. SPR-0010 (027) 142 
    Report Budget Number KLK466 
    NIATT Report #N03-07