Waitomo District Council’s roading contractors will soon start work to repair two sections of Taharoa Road, but it comes with a caution: there is no easy fix or long-term cost-effective solution.

General Manager Infrastructure Services, Shyamal Ram says due to the location, traffic, geological conditions, and weather events, Taharoa Road will require ongoing maintenance and rehabilitation.

A permanent solution, especially for the “Staircase” section, would cost several million dollars, which is not viable at this time and would be beyond Waitomo District Council’s ability to fund.

“The maintenance and emergency reinstatement cost over the last six years is $800,000. On average, we spend upwards of $50,000 on pavement maintenance and $10,000 on drainage renewals and maintenance each year on this road alone, the balance being spent clearing slips,” he says.

“There has also been a large increase in emergency works due to the increase in adverse weather events that are happening more frequently.”

During Cyclone Dovi in February 2022, Taharoa and Te Anga Roads were impacted with 17 over slips, six under slips and/or scour, four damaged culverts, and three fallen trees.

Two major storm events this year also impacted the road.

Repairs are planned for the 2023/24 and 2024/25 construction seasons with estimated costs up to $2 million.

Ongoing inspections and maintenance repairs are also programmed, including annual resealing and pavement rehabilitation programmes.

Two sites are planned for pavement rehabilitation and will be completed towards the end of 2023.

“The section of Taharoa Road known as the “Taharoa Flooding Section” is located along the low-lying area and Waikato Regional Council has very strict rules around working within and near the wetland,” says Shyamal.

“Resource consent was recently obtained to allow construction under strict control. That entire section of road is below the surrounding wetland due to regular silting.

“The proposed improvement to raise the level of the road to reduce the risk of flooding is programmed for the end of 2023. The value of this proposed works is $750,000.

“The “Taharoa Staircase” is a section of Taharoa Road which is also subject to ongoing ground movement.

“With repeating subsidence failures of this large scale, there isn’t a low-cost solution. Ongoing maintenance of the road surface and repairs when required gives the best value for money.

The road also has a speed restriction posted consistent with the risk and weekly inspections by the Road Maintenance Contractor monitor the subsidence issues.

Shyamal says a permanent solution would cost several million which is not currently viable.

“At this stage, maintenance will be ongoing to try and combat the continuous movement.”

The Taharoa Staircase section will have some minor pavement and drainage works done before the winter weather sets in. This work is programmed to start this month, weather permitting.