Conducting a geotechnical rock slope inventory and assessment for the City of Hamilton

Sustainable Infrastructure Planning and Slope Remediation Measures

The Niagara Escarpment creates a steep elevation change as it crosses throughout the City of Hamilton. Excavation of various rock cuts was required along the road alignments to facilitate road construction through the escarpment and connect the upper and lower part of the City. Since many of these cuts are near the roadways, rockfalls from exposed slopes pose a hazard for vehicle and pedestrian traffic. The City engaged us to provide engineering services for slope inspections, rockfall hazard assessments, and site assessment reports.

The scope encompassed 22 rock slope locations. We inspected the slopes and compared our findings to observations made during a 2015 initial assessment. Next, we applied the Ontario Rockfall Hazard Rating System (RHRON) to assess the rockfall hazards for each slope and provide a rating based on four parameters—magnitude, frequency, reach, and consequence of rockfalls. Keeping previous remedial work in mind, we reassessed the conditions of the slopes and updated the previous rockfall hazard rating for each one.

Following a qualitative risk assessment, we delivered our recommendations to the City and assisted with the prioritization of the next round of remedial and maintenance work to maintain the safety of those who travel across Hamilton’s roads.