New slip disrupts access through Haast Pass

Access problems between Wanaka and the West Coast were further aggravated by another major slip on State Highway 6 yesterday morning.

The New Zealand Transport Agency (NZTA) says it will be midday today at the earliest before a large rockfall about 15km south of Makarora is cleared and the highway opened again.

The road was also closed further west on SH6 yesterday at the Diana Falls slip site, where there have been nightly road closures for the past nine months.

Wanaka-based Diana Falls workers were unable to get through to manage the site because of the new 2000cu m slip blocking both lanes between The Neck and Makarora, NZTA senior network manager John Jarvis said.

The rockfall came down at 6am and was roughly 50m long and four to six metres deep, larger than one two years ago about 100m further north. Recent heavy rain was the likely cause.

Mr Jarvis said the site had previously been deemed unstable and scaling work was being carried out in the days leading up to the slip to remove loose rock.

''It did expose a bit more material once we got in there.''

The top of the slip was sluiced yesterday before contractors spent about three hours carrying out clearing work. The Minaret Station barge was used to ferry heavy machinery on Lake Wanaka to the north side of the slip.

There were indications some large boulders were buried in the debris, which could be difficult to move.

''We're not sure at all when we will be able to open it until we get back into it [this morning],'' Mr Jarvis said.

''We understand our customers will be inconvenienced by this situation and are making every effort to get at least one lane of the highway open as soon as it is safe to do so.''

The latest slip was nowhere near the scale of the Diana Falls slip and was unlikely to create significant ongoing issues. However, the entire stretch of highway between The Neck and Makarora was ''very vulnerable'', he said.

Only delivery drivers and Makarora residents caught between the two slips were allowed to travel through the Diana Falls site yesterday.

- lucy.ibbotson@odt.co.nz