Whanganui River trial dredging begins in bid to move more sediment faster

Whanganui Port project's current dredging solution uses a barge and excavator. Photo / Bevan Conley

A new piece of dredging technology is being trialled in the Whanganui River.

A cutter suction dredge will be put to work in the port basin from this week.

Whanganui Port project director Phil Wardale said the current dredging solution uses a barge and excavator.

“It’s unable to shift the amount of sediment we need, at an efficient pace,” he said.

The new trial dredging equipment would be in place during the rest of March and into April if operating well, Wardale said.

“Our procurement process is to look internationally, along with here in New Zealand, and this trial will help inform us of the best type of equipment to use for our specific purpose.”

The trial comes as the port revitalisation project Te Pūwaha prepares to apply for a long-term dredging consent for the port basin and river bar.

Wardale said sediment had built up because regular dredging of the Whanganui Port basin had not occurred for several years. This had affected the ecology of the port basin and access for commercial operators, boat owners and the Whanganui Coastguard.

The $62.85 million port revitalisation project is the first major infrastructure project to recognise Te Awa Tupua, the Whanganui River and its tributaries.

Led by iwi, project partners include hapū governance group Te Mata Pūau, Whanganui District Council, Horizons Regional Council, Q-West Boat Builders, and the Whanganui District Employment Training Trust (Port Employment Precinct).

The project aims to create a modern marine precinct and port asset while creating mauri awa (abundance for the river), mauri ora (abundance for the wider eco-system) and mauri tangata (abundance for whānau, hapū, iwi and the wider Whanganui community).

Wardale said there would be a focus on the ecological impact of the dredging.

“The dredging activity will be done in balance with owning the ecological impact that dredging creates and our commitment to Te Awa Tupua.

“As a project, we are not shying away from ensuring our contribution to the awa can enhance the wellbeing of Te Awa Tupua.”

The dredging application will also include a proposal to future-proof the port basin and reduce the flow of floating debris by closing a hole in the training wall.

The investment in Te Pūwaha includes a $31.8 million government investment managed by Kānoa – Regional Economic Development & Investment Unit.

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