Stop-Go lights at SH5 highway drop-out site

The dropout between Tarawera and Te Haroto as it appeared last weekend. Now the southbound lane will be closed until repairs can be made. Photo / Warren Buckland

A section of State Highway 5 about midway between Napier and Taupo will be down to one lane with traffic light control from Friday because of a drop-out threatening the road.

The announcement came just three days after nationwide Government highways manager Waka Kotahi New Zealand Transport Agency answered questions from Hawke's Bay Today revealing it was aware of the state of the dropout creeping up to the edge of the southbound lane between Tarawera and Te Haroto and had been monitoring it since more damage was caused in major rain events in late March and early April.

Truck drivers have been expressing fears for the dangers, including possibility the road could collapse beneath the weight of their vehicles.

In a late-Thursday statement, NZTA Hawke's Bay System Manager Martin Colditz said the decision to close the lane past the dropout on the advice of a geotechnical engineer - "to move traffic further away from the slip face."

"This will allow contractors to continue work to manage stormwater through the area safely and avoid the risk of traffic causing any further damage to the road while we identify the best course of action, next steps and timeframes for repair," he said.

Engineers will be on-site late next week, after which the NZTA expects to provide an update to the public.

In the meantime, the site will remain under traffic light control with a 50km/h temporary speed limit, and there will be restrictions for oversized loads.

"Please slow down, take extra care and be patient," Colditz said.

Highway upgrade campaigner Axel Alexander says the slip has "been there for over a year – possibly one-and-a-half years" and suspects NZTA had not done anything other than put in place plastic mesh fencing and monitor the site because of funding issues.

Hawke's Bay Today images taken just last weekend, and others on social media, highlight the mesh and fencing now suspended over the drop-out as it creeps closer to the traffic lane, and Alexander sent images to the NZTA.