Evaluation of the Effectiveness of Catchment Ditches along Ohio Roadways

The effectiveness of catchment ditches along Ohio roadways was evaluated for 100 sites with the Oregon Rockfall Hazard Rating System (RHRS), the New York State Rock Slope Rating Procedure (RSRP), the Colorado Rockfall Simulation Program (CRSP), and the Oregon Rockfall Catchment Area Design Guide. From the results of this evaluation, 48% of the ditches were ranked as adequate within an acceptable level of risk, 28% were ranked as marginally adequate, and 24% were ranked as inadequate. Although qualitative in nature, the ditch evaluation portion of the Oregon RHRS was found useful. None of the ditches evaluated met the Ritchie ditch depth criteria as used in RSRP. CRSP provided valuable information when the entire road cut was accessible for data collection. Because of slope height restrictions, the Oregon Rockfall Catchment Area Design Guide provided ditch evaluations for only 44% of the sites.