A submersible drone is being purchased by Tararua District Council to monitor ongoing issues with Dannevirke’s impounded water supply.
The remotely operated underwater vehicle (ROV) has been identified as an essential tool for inspecting the council’s water supply reservoirs.
The council’s Three Waters transition manager Peter Wimsett said they want an “eyes-on” approach to the interior of the dam to mitigate issues faced due to the impounded water supply.
The cost of the ROV is expected to be less than $50,000, and it’s hoped it will reduce the costs of outside contractors in the future.
It will mean the inspections can be done utilising an underwater perspective with sonar and cameras with a small robotic arm that can release dyes or hold equipment.
“A record of changes over time to the surface of the reservoirs can be used to identify potential problems and manage those,” he said.
The council already operates several aerial drones for inspection, 3D imagery and LiDar, which provide close to survey-quality information.
An extraordinary council meeting revealed plans that would include spending $3.2 million on a raw water pre-treatment plant, $400,000 on a raw water storage tank and $2.5m for a 6,000,000-litre treated water storage tank.
The delayed decision to put off repairs to the impounded water supply, or dam, was due to outstanding geotechnical investigations, supply challenges and issues with the liner system which meant that it is still operational, and inspections are carried out each day.
A Dannevirke public impounded water supply meeting last week allowed the public to express their concerns about the plans for the water.
Frustrations were raised at the meeting by the public around timelines and additional costs to ratepayers for the ongoing project.
The purchases will be funded through a loan that will be paid over a minimum of 20 years or the life of the assets.
The dam was built in 2013, and the initial leak was identified in the 1.5mm HDPE liner in July and September of 2021.
Further tears were identified in May 2023 - one the size of a cellphone and the other a pinhole tear - which had since been fixed, and no additional leaking was found.
The council has committed to fixing the water supply and has worked to build resilience through other options, which included finding potential bore sites and investigations into water extraction from the Tāmaki River.
Michaela Gower joined Hawke’s Bay Today in 2023 and is based out of the Hastings newsroom. She covers Dannevirke and Hawke’s Bay news and has a love for sharing stories about farming and rural communities.