A tomo that opened up on Trig Road South, Waihi, last Tuesday evening (19 June) also opened a can of worms that the Council has spent the last week investigating and repairing.
Network of holes
Staff and contractors swung into action at first light last Wednesday to uncover the extent of the problem, and discovered a network of “worm holes” caused by a stream heading underground and forming its own path under the road.
Hauraki District Council Group Manager Engineering Services Adrian de Laborde says the area has since been fully excavated to uncover and fill all the cavities as well as install a new culvert at the “new” stream level to contain the water flow.
“It was important to understand the full extent of the problem and fix it properly, rather than try and apply a band aid,” he said.
There was initially some speculation out in the community that the collapse may have been related to mining but de Laborde says this is definitely not the case.
“This is a completely natural phenomenon caused by natural erosion where water has gone underground and carved a series of voids, possibly over years, that have eventually broken through to the surface.”
Wet weather may hamper reseal
Repair work is expected to be completed by the end of the week (29 June) and it is hoped the road will be reopened before the weekend. However, wet weather looks set to hamper final resealing efforts.
“It’s likely the surface will be temporarily metalled until we get a drier spell of weather which will allow us to properly chipseal the area,” de Laborde said. “I’d like to acknowledge the exceptional work of staff and contractors to complete this work in such a timely manner in mostly cold and wet conditions. Thank you also to the local community and general public for your patience while we’ve worked to make this road safe again.”