Critical Brynderwyn Hills work to futureproof the route from extreme weather events is on track despite recent rain.
New Zealand Transport Agency/ Waka Kotahi (NZTA) is three weeks into its planned two-month closure of the Brynderwyns’ Hills.
Roading crews have been working around the clock and earlier this week were estimated to have cut about 76,500 m3 of soil, weighing about 99,500 tonnes.
The progress on a southern stretch of the State Highway 1 route was recorded in time lapse footage.
More than 520 staff have been inducted onto the project, including a dedicated kiwi sniffer dog named Pearl, an online NZTA update says.
Workers had been clearing vegetation, transporting machinery to various earthworks sites, doing earthworks, and installing permanent piling on two retaining walls.
A core sampling machine was being used to drill down five metres so engineers could check the strength of the pavement layers and its ability to hold horizontal nails to support the road and walls.
Soil nails up to 15m long would be used to stabilise slopes.
A five-tonne skid steer - nicknamed “Racing Snail” - with a broom is being used 12 hours a day to keep the site clear of debris and stop the road becoming slippery in wet weather.
Detour routes, which cost more than $5.5 million to upgrade ahead of the project, had been effective as vital links between Northland and Auckland. There have been two crashes on the detour routes - one involving a logging truck that toppled and blocked the road, and a collision between two cars.
Steve Mutton, Director Regional Relationships NZTA said, “We are making good progress, and the real advantage of the closure is the ability to work both day and night.
“The aim of this work is to create additional space on the corridor, which will allow better management for future events on the hill without disrupting traffic. It’s important that people understand this additional space is not an extra lane. In case of the next severe weather event we will then have room to clear slips and debris, minimising the need for lengthy, major closures.
“We’re creating extra room on the road and moving traffic lanes closer to the hill away from the more vulnerable side of the hill. Essentially, the work we are doing now will give us a safety zone we currently don’t have.”
The road reopens on March 27 for Easter then closes again on April 3 for further work.
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