Innovation on the job – stabilizing hazardous rock face in New Zealand
When New Zealand contractor Fulton Hogan was awarded a contract to remediate a steep unstable rock face overlooking the Port of Otago, it was faced with a number of challenges to deliver the project safely, within a tight budget, and in a highly visible location.
The project, known as the Flagstaff Hill Earthworks, was to stabilise a steep hazardous rock face next to the Port.
Also known as Observation Point, reclamation of areas of the port during the 1990s had resulted in an unstable rock face, with several slips, as well as rocks and boulders falling to the road below.
For the past 20 years, half the roadway at the foot of the face has been battered off with safety fencing to protect public roads and walkways.
The area is one of outstanding beauty, with views to Otago Harbour’s historic Quarantine and Goat Islands, and across to the Otago Peninsula.
A KiwiRail line for freight and daily passenger services during the cruise ship season runs adjacent to the site, while both locals and tourists use the road and tracks below for recreation.
Over the years, slips have caused closure of the road, while frequent rock falls and boulders have come down the slope.