Wellington Transport Alliance (WTA) - a maintenance and operations alliance of WSP, Fulton Hogan and Waka Kotahi - was busy reducing the risk of rockfall and hazardous slips along the Gorge.
A southbound lane was closed from Boxing Day to 8 January while the new safety measures were installed on the cliff face by abseiling workers. The work was scheduled over the holiday period when traffic volumes were at their lowest to minimise disruptions.
Work completed included the installation of approximately 2,700 m2 of draped safety mesh across three areas of the batter slopes in the Gorge to help reduce the risk of rockfall and slips. This involved 480m of drilling to install 135 rock anchors, and construction of a 195m-long catch fence.
Ngauranga Gorge is one of the main routes to Wellington. It's been prone to slips and rockfall over the years, including a large slip in 2017.
Wellington Transport Alliance Health and Safety Manager Mike Sarten says the job had many challenges including a steep gradient, a work site near a very busy highway, high winds, rain, heat and loose debris falling regularly that needed to be carefully managed.
Contractors worked to remove loose rockfall debris and vegetation in December before the mesh was installed, and then fragile rock at the top of the cliff slope was wrapped in strong mesh panels to contain potential rockfall.
Traffic management of the site was well executed with no major incidents or delays.
