Good progress has been made in recent days on the culvert collapse on a key highway connecting Dunedin with Port Chalmers which occurred at the end of last week, says Waka Kotahi NZ Transport Agency.

However Waka Kotahi Senior Network Manager Chris Harris warns that the repair will take several weeks given the number of key services (water, power, drainage) that are contained in this area and must be protected throughout any excavation work. “We will attempt to keep the highway open to two lanes at peak hours and other times wherever possible with a reduced speed limit.”

Work in weeks ahead

Mr Harris says that crews need to undertake a trial later this week to decide if the ground conditions are suitable for pipe thrusting. If successful, more equipment and new culvert pipes will be needed and this is expected to take about a week. “Then we need to connect a new pipe to a new inlet, which will take at least another week,” he says.

“The 11 kV cable repair by Aurora was tested on Wednesday (today) and the Dunedin City Council’s wastewater pumping pipe has been protected with backfilled material.

“We are using an inflatable bung to divert water away from the culvert and into other drainage outlets on either side of the damaged culvert in the event of rainfall affecting the site.”

Mr Harris emphasized the critical lifeline and economic importance of the SH88 route to the port and the need to keep it open to two-way traffic as much as possible given the lack of a detour.

“We have had a number of people from different organisations involved in this work ensuring their key assets which pass in close proximity to this culvert are protected – from Aurora, from Delta, from Dunedin City Council’s three waters team, as well as our own highway repair crew and a structural engineer managing the retaining wall repair.

“We thank all road users and residents for taking care around the large number of workers involved in this complex repair and their continuing courtesy as we work to reinstate this critical link to the West Harbour area,” says Mr Harris.

Work well underway at Ravensbourne, between Dunedin and Port Chalmers, by Waka Kotahi. People from a number of organisations are ensuring their assets are protected while this work is progressing:

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