Koputauaki debris dam release and closure of Koputauaki bridge

Published on 06 February 2023

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Update: 4:15pm

Effective multi-agency co-operation has seen the safe completion of an operation intended to initiate a controlled release of excess water from the Koputauaki debris dam.

Between 2pm and 3pm, Fire and Emergency New Zealand USAR staff oversaw an air operation that involved monsoon buckets full of water from the debris dam, being dropped on the debris dam, slowly eroding the earth until water could begin to flow steadily into the Waiwhango river.  Staff from NZ Police along with council contractors, working with Koputauaki community members, kept the area downstream of the dam clear of people and vehicles.  


Initial assessments indicate the operation has had some success in increasing the flow of water from the debris dam.

“This could only be achieved by working together with other agencies and community groups” Civil Defence Controller Julian Snowball says. “This operation is proof of the power of collaboration.”

Our team will continue to monitor this increased flow of water and assess whether additional action needs to be taken to further increase the amount of water leaving the debris dam. This will depend on multiple factors such as land stability and rainfall.

“The are other plans, if we establish that today’s course of action ultimately does not reduce the volume of water sufficiently, to ensure the safety of the community. The safety of the public is our main priority” says Snowball. 

To allow time to see the extent of the results, reassessment will take place tomorrow. In the meantime, the Koputauaki bridge will re-open with traffic control in place and at-risk residents will remain evacuated.

Information will be provided as it comes to light. 

Original release

A controlled release of water in the Koputauaki debris dam has been scheduled for 1pm today.

Investigations have revealed the debris dam contains approximately 10,000 cubes of water, about the size of a rugby field filled with water 2 meters deep, posing a risk to the community due to the possibility of a catastrophic failure. Seven homes, the Koputauaki bridge and the community marae are at risk of damage in the event of a dam failure.

A potential solution has been identified, which is intended to relieve the dam by a semi-controlled release of this built-up water. This involves using a helicopter and monsoon bucket to slowly erode a specific area of the debris dam so that trapped water can begin to flow steadily into the Waiwhango river. This operation is currently scheduled to take place between 1pm and 6pm, with the release process taking approximately 1.5 hours, weather dependant.

This operation is lower risk and has the potential to alleviate imminent risk to the community. It is also a temporary solution, so the debris dam will continue to be monitored and actions to protect our community if water accumulates again will be reassessed.

To ensure safety, the Koputauaki bridge will be closed from approximately 12:30pm. If you need to use this route to leave, please make sure you do so before this time. An alternative route on Kennedy Bay Road will be open, however this is not a sealed road and may be difficult to navigate in large vehicles or for vehicles towing trailers or boats.

“Safety of the community is absolutely paramount” says Julian Snowball, the Civil Defence Controller. “If you are looking to leave Koputauaki, please consider doing so before the bridge closure.”

Our Council will update the local and wider community with any updates as they arise.

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