A slip near Mokau means SH3 will be closed until at least Thursday noon.
The NZ Transport Agency is advising motorists wanting to travel between Taranaki and the Waikato that State Highway 3, south of Mokau is to remain closed until at least midday Thursday 22 September.
This follows a major slip blocking the road from Sunday 18 September, triggered by a large amount of rain over the weekend.
Getting this road open safely is a top priority for us. We know that it is the main route between Taranaki and the Waikato and the road closure and long detour are frustrating and inconvenient for many people.
"The advice from our geotechnical engineers is there is still currently risk of further major rock fall at the site and it is not safe for either contractors or motorists to be on or near the site," Karen Boyt, Regional Performance Manager, NZ Transport Agency says.
Starting from yesterday and continuing today, helicopters with monsoon buckets of fresh water have been used to wash down the remaining loose rock. Currently abseilers are scaling the rock face to check all the remaining rocks that haven't washed down, and knock any off loose rocks. Only once geotechnical engineers have confirmed that the cliff is stabilised, will contractors be able move into action to clear the rocks, allowing the road to open to one lane.
"Geotechnical engineers are undertaking thorough inspections of the entire slope face through rope access and photo inspections. They will use this information to make a decision on the stability of the remaining rock face.
"Once the rock face is confirmed as safe, our contractors will then be allowed in to remove the additional rocks and material that has been brought down onto the road, and to clear the road to make it safe for motorists, and allow us to reopen the road," Ms Boyt says.
"We estimate that over 200 cubic metres of rocks and debris will need to be cleared, and contractors will be working on site for the best part of a day. Once the road has been cleared, concrete barriers reinstated and the road opened to traffic, we will then begin investigation and design of the more permanent engineering solution to replace the wire mesh and ensure long-term protection of the slope. This installation will also require temporary traffic management, and we will appreciate motorists' on-going patience while we carry out this important repair and mitigation work," Ms Boyt says.
The Transport Agency will provide another update tomorrow (Wednesday) afternoon with more detail on the timing for clearing the rock and debris, and when the road can re-open.
"We appreciate people's patience while we work to get this important route reopened. While there is still the risk of further slips, the road must stay closed for everyone's safety," Ms Boyt says.
Until State Highway 3 opens again, motorists are advised to use an alternative route via State Highway 1 or State Highway 4 via Whanganui, which will add approximately three and a half hours to the journey.
Other local road routes via Ohura and State Highway 43 are not suitable detours for State Highway 3 traffic. They are narrow, windy and unsealed roads not suitable for heavy vehicles or those unfamiliar with the roads, and are not capable of supporting larger volumes of traffic. State Highway 43 has also been subject to closures over the weekend due to weather-related slips.
The NZ Transport Agency's website - www.nzta.govt.nz/traffic - will be updated with road status information, and we will have electronic message signs at key routes advising whether roads are open.
Transport Agency contractors are also on site at a slip at Tangarakau Gorge, State Highway 43. This section is currently open to one lane, under stop/go management, so motorists can expect short delays as this route is cleared. Motorists should continue to check the Transport Agency's website and social media and the electronic message signs to see if the route is open.
"As conditions can change rapidly, we advise people to check the latest road updates before they get on the road. This could mean delaying your journey," Ms Boyt says.
Motorists can get real time information from:
· 0800 4 HIGHWAYS (0800 44 44 49)
· www.nzta.govt.nz/traffic
From 6am to 7pm weekdays, updates will be available on:
· www.facebook.com/NZTAWaikatoBoP
· www.twitter.com/NZTAWaiBoP
· www.twitter.com/NZTACNI
· www.facebook.com/nztacni