The massive slip just south of Knights Point, looking south towards Haast. Photo: Andrew Dempster
The New Zealand Transport Agency needs to get on with securing the Haast Highway, which is at risk of slipping into the sea, Westland mayor Helen Lash says.
The area, known as the Epitaph Cutting underslip is just south of the famous viewpoint Knights Point, where State Highway 6 clings to a cliff, with the slip falling away to the sea about 300 metres below.
Lash said it was a lifeline for the entire West Coast, and a "grave concern".
The highway is looking increasingly vulnerable at that point.
It is something already acknowledged in new funding to NZTA in this year's budget, but meantime the prospect of the road slipping away is worrying West Coast community leaders.
In the past decade the State Highway through South Westland has been severed several times, and some times for weeks at a time, severely impacting the communities along its path and the entire South Island tourist trail.
"It's of grave concern," Lash said on Friday.
"It has sat for some time as it is (but) some severe weather can restart it at any time. It's a great concern because it's a lifeline road."
Local communities relied on it for their industry and services, as well as the tourist economy.
"I wish to goodness that NZTA would acknowledge it and do something."
Lash said a recent general briefing to the Westland District Council gave little reassurance, but for those who knew the slip area it was clearly "very vulnerable".
"The worst thing at the moment is everyone is waiting for action."
Lash said Westland had "several roads of concern" at present but State Highway 6 at Knights Point was the most urgent.
"That's certainly the main one."
West Coast Regional Council chairperson Peter Haddock, on the West Coast Regional Transport Committee for over 15 years, said the slip had been on the committee's agenda for years.
It was particularly a problem because there was no alternative route past that coastal section of highway.
"I don't think there are many options but retreat back. This area does need attention. We can't just wait until the road drops out. It's a major tourism route."
It would be disastrous if the slip suddenly let go, cutting access altogether in "the middle of a tourist season".
"The cost is phenomenal of having that route out for weeks or months."
It risked again the region getting "a bad name" and being eliminated as a risk-free option for visitors and organised tourist operators coming through.
This had certainly been seen previously with the natural events severing the road for days or even months on end further north at the Fox Hills, Mount Hercules, the Waiho (Waiau) and Wanganui bridges, and towards Lake Ianthe.
"Tourists then get a bit of a thing in their head that there's a risk, so they plan tours so they don't have that (risk)."
Haddock said the matter of route security had been raised at South Island regional transport sector meetings.
"I do know they're stretched for funding but you eventually have to make a plan. We've got to come up with a plan if (the slip) does start failing."
In the latest Budget announced in May, the government put $11 million towards land transport resilience work on the West Coast, including "remote monitoring and stabilisation" of the Epitaph Cutting underslip.
Other vulnerable road sections under that funding include: Kellys Creek near Otira, Candys Bend in the Otira Gorge, Maybille Bay on the Coast Road, the Inangahua Junction slip on State Highway 6; and at Blackwater Point in the lower Buller Gorge.
NZTA said plans for remote monitoring and early warning systems at Epitaph Cutting would provide "real-time data" on various key metrics at the site.
Funding set aside in the budget for road resilience for the West Coast State Highway network was to address various vulnerable points in the network, including the Knights Point area.
"This will let us identify changes early and provide early warning on any changes in site conditions to our contractor and the public," NZTA central and lower South Island regional manager Mark Pinner said.
It was also undertaking a business case for the resilience of State Highway 6 in South Westland.
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