Work is underway at Maungauika / North Head in Devonport to maintain parts of the historic defence tunnels.
The work includes reinforcing some of the original iron struts within the concrete structures and giving additional strength to lintels above doorways. Core testing is also scheduled to help determine the future programme of general upkeep.
While most tunnels will remain open to the public, some sections of the Northern and Southern Battery will be closed from this week. Some small areas above ground will also be fenced off while this maintenance work is carried out on the structures below. Signage is in place.
The maintenance work will be completed by April 2020.
Nick Turoa, Tūpuna Maunga Authority Operations Manager explains that the work is standard maintenance and there is no risk to public safety if people remain outside of the cordoned areas. Similar works have been carried out in the past on other heritage structures on the maunga.
“The construction of the tunnels dates back to the late 1800’s, and as with any heritage structure of that age, strengthening work may be required over time to preserve them,” says Turoa.
“Through the process to transition the management of Maungauika / North Head from the Department of Conservation to the Tūpuna Maunga Authority mid-2019, we have been working with engineers to look at any remedial works required on all of the heritage structures, including the tunnels.”
“Engineers have identified several areas that, due to natural corrosion, need additional strengthening to maintain the integrity of the tunnel structure into the future, and that’s the process we are working through now.”
“We have also worked with heritage architects to ensure that all remedial works in the tunnels do not compromise the heritage values of the structures and that work follows best practice for managing heritage assets.”
“In the meantime, the engineers have advised us that the current day to day visitor entry to the tunnels is safe provided they remain out of the cordoned areas,” says Turoa.
Coastal Track Closure
The coast track that runs around the base of Maungauika / North Head has been closed since August 2019 due to a large landslide that took place during a storm event. Over the past months the Tūpuna Maunga Authority have been working with geologists and geotechnical engineers to ensure the structural stability of the cliff face.
Assessment works have now been complete. Engineers have recommended scaling the cliff face of loose materials and removing dead vegetation to minimise risk of further landslide or loose rocks falling on track users.
Works on the cliff face will begin early 2020 and the coastal track will be re-opened once engineers deem it is safe for public access.