Stopbank upgrade begins at 'vulnerable' Awatoto

An upgrade designed to reduce risk during a one-in-100-year flooding event has begun on the Tūtaekurī River stopbank at Awatoto.

The 3.6km work on the Brookfields Lower stopbank will strengthen and raise it, but won't protect the area from a Cyclone Gabrielle-size flood.

The stopbank will be widened up to 2m on the river side and raised by up to 0.6m in places.

Hawke's Bay Regional Council (HBRC) councillor Neil Kirton said the upgrade, from Brookfields Bridge to the SH51 railway bridge, on the left bank of the Tūtaekurī River looking downstream, marked a significant step forward for the community.

"This is a significant investment in the safety of Awatoto homes and businesses," Kirton said.

"Cyclone Gabrielle showed us just how vulnerable this area can be, and while no stopbank can stop an event of that scale, this work will have a genuine impact in more common flood events."

Cyclone Gabrielle inundated Awatoto's industrial area, leaving floodwater mixed with wastewater, industrial chemicals and other contaminants.

Floodwaters up to 2m deep swamped homes and businesses after the stopbank overtopped and breached.

A HBRC spokesperson said the upgraded stopbank won't protect the area from a Gabrielle-scale event, but would mitigate floods with a 1% chance of happening in any year.

They said a Cyclone Gabrielle-level event in the Tūtaekuri River has a 0.25% chance of happening in any year, or a one-in-400-year recurrence probability.

During construction, the cycle trail between Awatoto and Johns Road in Meeanee will be closed. A detour using the iWay route from Johns Road through Te Awa will be in place.

Kirton said he appreciated the community's patience.

"We know changes like this can be disruptive, especially with the cycle trail detour, but we're grateful for the community's patience while we carry out this important flood resilience work."

The upgrade is part of HBRC's $256.5 million flood resilience programme, including upgrades to stopbanks, telemetry sites and pump stations, new flood infrastructure, and reviews of existing flood schemes.

Funding is managed by National Infrastructure Funding and Financing under the Government's Cyclone Recovery Programme, and provides around 75% of the total cost.

HBRC covers the remaining costs.

The spokesperson said improved drainage to the stopbank would also add to Awatoto's resilience.

"The council will also be carrying out site establishment works to upgrade the Awatoto drainage pump station (formerly known as Mission pump station)."

The upgrade is expected to be complete by April 2027.