SLIP repairs are promising five weeks of day time road closures on SH31. Photo Andy Campbell
Repairs to the large slip on Kāwhia Rd begin on Tuesday next week with Waka Kotahi promising lengthy day time road closures.
An engineering technique called soil nailing will strengthen the site but because it is very narrow, with a steep drop-off, the road will need to be closed to traffic while work is happening.
“The plan is to close the road each weekday at 8am, we will work until 12.30pm then open it for one hour, closing it again from 1.30pm to 5.30pm,” Waka Kotahi System Manager for Waikato, Cara Lauder, said.
“There will be no weekend work, with the road remaining open at single lane, but these daytime works and closures will be needed for about five weeks.”
In an emergency situation the site – about two kilometres downhill from the lookout, could be cleared to allow emergency vehicles through, she said.
Kāwhia access during the road closures will be via SH39 to Ngutunui Rd, Pekanui Rd, Okupata Rd and Oparau Rd back on to SH31.
The rural roads with some unsealed stretches will take about 10 minutes longer than SH31.
“I hope most people can get through our worksite while it is open but for those who can’t, this alternative route is available for light vehicles and we advise drivers to take care,” Cara said.
The slip has reduced the highway to a single lane with traffic lights since cracking developed in February. There has since been extensive geotechnical work to understand the cause of the problem and design a solution.
“The slip site is between two retaining walls and the piling under those walls we found was in good condition and provides stability for the work ahead,” Cara said.
“With reasonable weather in the past month and some initial work the slip has stabilised and we have been able to keep the road open. That has been a good result as this is a vital route for the Kawhia community, farms and other businesses.”
About 800 vehicles a day use Kāwhia Rd and about 13 per cent are trucks.
