NZTA begins work on restoring access to SH4 Raetihi

3 MinutesBy NZ Trucking magazineNovember 11, 2019

The NZ Transport Agency has begun work to build a temporary road to reconnect State Highway 4 between Raetihi and Wanganui.

The road has been closed since early October after it was significantly damaged by a major slip. The site continued to move in the weeks following the slip, however geotechnical engineers confirmed that it had stabilised and is now safe enough for ground crews to begin work.

“Our crews are now preparing to enter the slip site, where we will begin drainage and revegetation before starting work to build a temporary alignment to reinstate the road,” said regional transport systems manager Mark Owen.

“We know from feedback we‘ve heard that it‘s important we restore access to the route, even if it is temporary and restricted. While we cannot say exactly what this temporary road will look like until we have fully assessed the site, we are aiming to open at least one lane to traffic as soon as it is safe to do so.

“Early indications suggest that a full temporary road could be completed early next year, however this is subject to further assessment as we work our way across the slip face.

“It is likely that once the temporary road is open, there will be limitations on its use. The road will be under constant observation and if deemed unsafe at any time, will be closed immediately.”

There are several other sites along State Highway 4 between Matahiwi and Wanganui where the road has resilience issues and in some places is down to one lane.

The NZTA has a programme of summer construction works to address these sites. Some are subject to final consenting and landowner agreements, so could take two years to complete.

“At the same time, we will be continuing to investigate long-term solutions to reinstate the road. This will take more time as we work through options to strengthen the highway‘s resilience so that it can better withstand the challenges of the unique topography and severe weather events.

“Locals, road users and businesses have been very patient and understanding and we are committed to restoring access to this critical route for them as soon as possible,” Owen said.

The recommended detour route is via State Highways 1, 49 and 3, which will add at least one hour to the journey between Raetihi and Wanganui.

Alternative routes, including River Road and Fields Track, are not suitable for heavy vehicles or large volumes of traffic. While these roads are open to local traffic, the official detour route via the state highway network is the safest and fastest route available.