End in sight for state highway slip repairs

The NZ Transport Agency says it’s progressing towards reopening State Highway 11 between Paihia and Kawakawa before the end of April.

SH11 has been closed to all traffic since heavy rain from ex-tropical cyclone Fehi brought down a huge slip above the road on February 13.

“We should have reached a point in stabilising the hillside over the next couple of weeks where we can safely open the road to traffic in the morning and evening for a limited time under traffic control,” NZTA Northland system manager Jacqui Hori-Hoult said last week.

“It will depend on the weather and continued monitoring of the slip and the risks it presents.

“We will have to stop work while the road is open, but it will allow locals and tourists to get through and not have to drive the detour route, which can add up to 30 minutes to their journey.”

Favourable weather had helped crews make good progress on the slip, she added. They had been working on the hillside high above the road from the top down, initially removing about 200 cubic metres of loose material a day but now taking out between 800-1000 cubic metres a day.

“We have reached the unstable material above the slip by cutting two five-metre-wide benches, or steps in the hillside, and have so far cleared about 12,000 loose cubic metres of earth and rock,” Ms Hori-Hoult said.

“Safety is paramount. We can’t work on the hillside when it’s wet, and we haven’t opened the road because of the risk of the unstable material falling on to the road.

“There’s a layer of about 8500 cubic metres of material sitting on top of other loose material, so it’s very unstable, and the risk since February has been that it could move at any time. We had planned to use explosives to break up the layer, but we’ve worked our way down to a level where we can remove it now without blasting.”

The slip clearance entered a new phase last week, where instead of carting material off the top of the hillside crews were pushing it down the slip face to remove it from the road.

“This is a great result, but the large amount of material being pushed on to the road is another reason why we can’t open the highway any sooner,” she added.

“This work is more than ever reliant on good weather, so I have to stress that our end of April target is weatherdependent. Our team reviews progress on a daily basis, as the transport agency is very conscious of the importance of the SH11 route to the Bay of Islands for locals and tourists.

“We’re working to reopen the road and reconnect communities as soon as possible.”

The NZTA thanked local communities and visitors to the region for their patience and understanding while it worked to restore the SH11 connection as quickly as safely possible. ■ Locals can sign up at www.nzta.govt.nz/sh11-lemons-hill-slip to receive email updates on slip clearing progress and details of how and when the road will be reopened, or go to www.journeys.nzta.govt.nz/sh11