EAST GATE SLIP

Fiordland in the lower South Island of New Zealand is a very high rainfall intensity area with high landslide and rockfall hazards. The area is surrounded by its mountainous terrain and stunning landscape. Located in the region is Milford Sound, a world-renowned tourist attraction. SH94 Milford Road is the only route for tourists travelling in and out of the tourist destination from a nearby town- Te Anau. One of the sites along Milford Road that has been impacted by rockfall and shallow landslides over the past decades is known as ‘East Gate Slip’, 87 km North of Te Anau. Historical data maintained and recorded by the MRA suggest that most of the rock sizes fallen over the years range between 0.2 m up to a maximum of 1.0 m in diameter.

A 2000 kJ Maccaferri RMC200A certified fence was installed at some distance from the road level to intercept any rock fall and moderate the level of shallow landslide. It has been identified that the fence is designed for rock sizes of between 0.5 m to 1.0 m in diameter with multiple impact scenarios. Moreover, the fence can arrest shallow landslides. These properties bring the assessed risk levels to an acceptable level. Immediately upon completion, the fence was impacted by fallen trees of 400-500 mm in trunk diameter. The fallen trees were successfully stopped by the fence with marginal activation of the energy dissipater, no replacement of any fence components was required as the impact energy was minor.