Raglan road: Work begins to build diversion around closed section of SH23

The closed section of SH23 known as the Raglan Deviation, pictured on Tuesday February 7. Photo / Waka Kotahi

Urgent work has begun to build a temporary diversion road around the damaged section of State Highway 23 (SH23) between Whatawhata and Raglan which was closed last Wednesday after a major slump in the wake of torrential rain.

Waka Kotahi NZ Transport Agency is now constructing the temporary diversion through private property and hopes it will be two lanes. So far there is no opening date confirmed for the diversion. The road - the crucial link between Raglan and Hamilton - was fully closed following a serious slip on the section known as the Raglan Deviation.

Waka Kotahi says the diversion plan started to take shape on Friday, and after the agency’s team met with landowners, fence and tree removal began. Earthworks will be carried out over the next few days to create the new temporary road.

“We are very grateful to landowners for their generous co-operation, and to Vodafone NZ for enabling us to work within close proximity of the fibre optic cable that runs through the site of the slump,” says Waka Kotahi System Manager for the Waikato, Cara Lauder.

The closed section of SH23 last week before it slipped away. Photo / Waka Kotahi

The new temporary road will be raised to protect the cable, which is not exposed by the current slip. The cable is around 600mm deep. “While we cannot give a firm opening date at this stage, we want to assure the community that every effort is being made to create access as a matter of urgency,” Lauder says.

“The temporary diversion road allows us the time we need to thoroughly investigate and plan the long-term restoration of SH23.”

The slump continues to move, and geotechnical testing, including drilling, is ongoing.

“While SH23 remains closed, our contractors are taking the opportunity to bring forward some planned resurfacing work to a steep section of the deviation further west. This work is scheduled to be carried out from Thursday 9 February 9 until Saturday, February 11,” Waka Kotahi says.

The agency says it will provide another update on the expected timeline for the diversion as soon as we can.

The official detour route remains Ohautira Road, Waingao Road, Herschel Street, Ellery Street, Whatawhata Avenue, Ngāruawāhia Road, and Horotiu Road to rejoin SH23. Waka Kotahi says please be careful and drive to the conditions, as it has tight, winding sections.