The new temporary diverson road on SH23 is raised to protect the fibre optic cable running under the site. Photo / Waka Kotahi
The new temporary diverson road on SH23 is raised to protect the fibre optic cable running under the site. Photo / Waka Kotahi
The main route to Raglan should reopen on Saturday, with the completion of a two-lane temporary diversion road that skirts the serious slip that closed State Highway 23 on February 1.
Waka Kotahi NZ Transport Agency said yesterday that in spite of heavy rain earlier this week affecting work on the diversion through private property, the final pavement work is under way.
“We are delighted to be restoring road access for all traffic on this crucial link between Raglan and Hamilton, as we know how important it is to people in this community,” Waka Kotahi system manager for Waikato Cara Lauder said.
“Our aim is to get this road open by midday Saturday. If we can open it earlier, we will. Road users should keep an eye on the Waka Kotahi journey planner and our Facebook page for updates.
“This could not have been done without the generous co-operation of the landowners, or without the Herculean efforts of our work team, who put in many long hours to make this solution a reality.
The closed section of SH23 pictured on Tuesday February 7 after the road slumped. Photo / Waka Kotahi
“Within days of the initial slip, we were able to begin tree felling and the earthworks needed to construct the temporary diversion road,” Lauder says.
While SH23 was closed, Waka Kotahi contractors Fulton Hogan took the opportunity to bring forward some planned resurfacing work to a steep section of the highway further west. This will be completed in time for the opening of the diversion road, preventing further disruptions.
The new temporary diversion road will restore the crucial main road link between Raglan and Hamilton. Photo / Waka Kotahi
The new temporary road is raised to protect the fibre optic cable running under the site. The cable was not exposed by the slip, and the ground over it was covered with protective metal plates while the tree felling and earthworks were under way.
The temporary diversion road will open with a speed restriction of 60km/h but will add only minimal extra time to the journey between Raglan and Whatawhata, Waka Kotahi said.
Lauder said that the slump is still active. “It continues to move, and geotechnical testing, including drilling and core penetration, is ongoing. We have not yet got the full picture of how Cyclone Gabrielle has impacted the site, and the ground was already saturated due to the unprecedented rainfall over January.”
The slip significantly worsened after Cyclone Gabrielle. A section of the highway nearly 30 metres long dropped around 2.5m, and the slip crossed over the centre line.
“The temporary diversion road allows us the time we need to thoroughly investigate and plan the long-term restoration of SH23,” Lauder said.
SH23 between Whatawhata and Raglan was closed on February 1, after the slip developed on the section known as the Raglan Deviation.
Earthworks on the temporary diversion road were halted on the morning of February 12 due to a serious incident on a nearby worksite.
The site is under full investigation and the matter is with the police and WorkSafe.
Timeline
●Monday January 30: SH23 closed to one lane due to cracking.
●Tuesday January 31: Crack became 300mm drop.
●Wednesday February 1: Drop became slump. Geotechnical assessments under way.
