A dropout occurred within the road formation and undercut and removed the road pavement along Pīpīwai Road. Road access was also affected by the slips.
Emergency remedial works were actioned to allow the road to reopen to traffic. To stabilise the wide area of land slippage along the road section, LDE were engaged for design remediation and construction supervision services.
Geotechnical assessments, testing and analyses were undertaken to determine the extent of the landslides, then using the data and findings to facilitate specific design solutions.
The remedial design involved the construction of a cantilevered timber pole retaining wall of length 35m at the centre of the site and an anchored steel column retaining wall of 9.9m long at the north of the site. A shear key for a wide area of land slippage affecting the road was also included.
Client: Far North District Council