Access through State Highway 3 between Taranaki and the Waikato was further secured last week with the completion of slip protection works at Mokau.
The NZ Transport Agency (NZTA) has carried out drainage works and installed 3600 square metres of draped reinforced mesh on the bluffs at the mouth of the Mokau River to reduce the risk of rock falls in this area. The drainage works will also help prevent slips by channelling water away from the slip-prone bluff face.
In September this year a slip caused a brief closure of SH3 just south of Mokau after heavy rain.
NZTA State Highway Manager Kaye Clark says the NZTA is doing all they can to help prevent further rock falls from closing the highway and posing a hazard to passing motorists.
Mrs Clark says, “Ongoing erosion due to the steep slopes, unstable soils, lack of vegetation and high rainfall has made this area vulnerable to slips. While there is still a possibility of further slips occurring, we hope that these recent works will stop that happening. Our maintenance contractors will be closely monitoring this site, particularly in periods of heavy rain.”
Mrs Clark says draped reinforced mesh is one of the simplest ways to reduce rockfall hazards. The mesh curtain is designed to guide slippage material to the foot of the slope and away from the road. It is also designed to allow rocks and debris to be easily removed.
Similar treatments elsewhere in New Zealand and internationally have proved to be extremely effective.