Rangitīkei River Climate Resilience project completion provides future protection against floods

Work has been completed on the Rangitīkei River Climate Resilience project which increases the river's capacity to handle large flood events.

The completion of the Rangitīkei River Climate Resilience project will increase the river’s capacity to absorb larger flood events.

The work was one of four climate resilience and flood protection projects in the central region carried out by Horizons Regional Council.

The other locations include the Palmerston North stopbanks, Lower Manawatū Scheme and Te Awahou Foxton Flood Mitigation.

Horizons catchment operations group manager Dr Jon Roygard said the Rangitīkei River project would create a more resilient approach, both economically and environmentally, to river management downstream of the Bulls Bridge.

“We worked to give the river more room to move by giving it a wider corridor, increasing its capacity to handle larger flood events and allowing for more natural dynamic changes,” Roygard said.

“Dispersing water across a wider area during flood events through this wider corridor will help to take pressure off stopbanks and other infrastructure.

“This project had many social benefits, including ecological enhancements through putting Horizons leased land back into native vegetation, providing employment and training to local businesses and iwi, and creating new amenity, such as upgrades to the Scotts Ferry access pathway.”

Work started in late 2020 and continued through the Covid-19 lockdown, which Roygard said posed some challenges.

The project was completed in June.

Work had been estimated to finish in 2024 but Horizons received a year’s extension after Cyclone Gabrielle in 2023, which slowed progress.

Roygard was pleased the work was now complete.

“It has been a big project for the Rangitīkei River. We have done a mix of works there and it has given us a chance to put the river back in a bit more of a natural way of working so it’s got the ability to use its own power to move the gravel through.

“It has really been a great opportunity for the region to do that work.”

The majority of funding for all four projects was through the Government-administered Regional Economic Development and Investment Unit - Kanoa, worth $26.9m.

The external funding contributed to 75% of the cost.

The Rangitīkei River Climate Resilience project cost $6.045m, with Horizons and landowners contributing 27% ($1.656m).

Roygard said the money spent now would contribute to future savings, with research from Before the Deluge business case showing every $1 spent on flood protection meant $5 to $8 of direct losses avoided.

Roygard said it was “an extremely strong ratio for large-scale infrastructure projects”.

With the suite of projects complete, Horizons’ capital programme for the coming years would focus on Feilding, Palmerston North and work associated with the Te Pūwaha port development project in Whanganui.

Roygard said another core focus would be on asset maintenance and management to keep communities safe from the impacts of flooding.

“We are also well advanced on a regional flood vulnerability study and hope to present the findings later this year,” he said.

Fin Ocheduszko Brown is a multimedia journalist based in Whanganui.