A section of Toronto, Canada’s scenic Colonel Danforth Park recently underwent a major slope restoration project after a large section of an adjoining 1.5h:lv slope failed. The slope had eroded to the asphalt edge of a neighborhood road (Colonel Danforth Trail) situated at the slope’s crest, making it dangerous for vehicles to travel on the road. Quick action had to be taken if the road were to remain passable.
Ensuring the permanent stability of the slope was the critical factor in engineering the solution. Return repair trips to the site would be expensive and laborious, since access to the slope for large equipment was difficult. Although secondary, minimizing impact to the environment was also a consideration as the site is part of a scenic park setting. Once restored, the slope would need to withstand continual erosive forces, as well as blend in naturally with the surrounding area.
The job was further complicated by the reinforced slope’s hard granular composition. The slope, by itself, would not be able to sustain the vegetation needed to blend in with the rest of the park, and the slope’s steep face prevented topsoil from simply being distributed down the slope.