Work to remove the bulk slip material from the middle of the slip face in the Waioeka Gorge is likely to be completed in 3 weeks time, says the NZTA.
NZTA Bay of Plenty state highways manager Brett Gliddon says contractors are hopeful the 30,000 cubic metres of slip material will be completely removed from this middle slip face area in a few weeks.
This mass of material referred to by the NZTA as the ‘whale-back’ has been difficult to remove, as creating the tracks for the machinery to get up the slip face and around this area has been hampered by falling debris covering its track.
“We have had some challenges over the last few weeks, but we are making steady progress and our contractors are confident that this material will be completely removed so we can start the process of clearing the rest of the material from around the base and the state highway”.
Mr Gliddon said also hampering the progress has been the recent identification that there is another area of the slip face that has shown signs of instability.
“There is an area on the top left of the slope where existing fractures have shown signs of expanding, we are monitoring this regularly to determine whether this is natural top soil movement; or whether there is another reason for this occurring”.
He says if work is required to stabilise this top left slope area, it be undertaken in time before the rest of the excavation work commences.
“If work is required, it is likely to be benching before a wire netting is installed to protect this area, we are confident that our contractors can have any work required completed in time for us to start clearing the rest of the debris from the base and off the existing state highway”.
In the meantime, motorists continue to use the temporary diversion route around the slip area which has been open for the last month.
“The temporary road has remained open without any major issues, there are still minor delays which are on average 2-3 minutes through the single lane operation, but we have had no complaints and we continue to have spotters on site all the time monitoring the slip face work while motorists are using the temporary road”.
Mr Gliddon says when work to clear material from around the base and off this area and SH2 starts, there should be minimal disruption to motorists using the temporary diversion route.
“The existing state highway is located behind the concrete barriers that separates the temporary road from the slip face area, we expect there to be minor disruption to motorists when the excavation work begins, but we will have a clearer idea in a few weeks time what those disruptions will be”.
For up to date information on the Waioeka Gorge operation visit our website www.nzta.govt.nz/waioeka-gorge(external link) or to find out the latest temporary diversion route information go to ‘Current Highway Conditions’ from the Waioeka Gorge website or call 0800 (44 44).