Waipawa stopbank upgrade

This project strengthens a 3 km stretch of stopbank from Coronation Park to Rathbone Street, along the left bank of the Waipawa River.  

It will upgrade the stopbank to the 1-in-100-year protection standard – also known as 1% AEP – used across Hawke’s Bay’s major flood schemes. The design draws on updated post-Cyclone Gabrielle flood modelling and includes an additional 700mm of freeboard – a safety buffer to allow for uncertainty and take climate change into account.

In practical terms, this means the stopbank will be up to 2 m higher than it is now - the height increase varies along the section as some sections are closer to or at the 1% AEP required height. We’ll also reshape the batter – the sloping side of the stopbank – so it meets current HBRC design standards. In some places, that means the stopbank will be up to 1.5 m wider.

A flood scheme is the combined system of flood defences in a catchment. That can include stopbanks, pump stations, floodgates, erosion protection, planting and other works that help manage flood risk and support the way the river system performs.

Each scheme is designed to a set “level of service”, or performance standard. That is usually defined by the size of flood the scheme is designed to manage – for example, 1% AEP.

Our resource consent was lodged in June 2026 and – all going well – we plan to start construction in July. We expect the main construction phase to be completed by the end of 2026, though there’ll likely be some tidying up work after that – reinstating the limestone top, planting, grassing and landscaping.

Central Hawke’s Bay company HES Earthmoving is our main construction partner for the project. 

Gravel naturally moves down our rivers, especially during floods. Over time, it can build up in places, change how floodwater moves through the river channel, and put pressure on our flood protection network.

Careful gravel extraction supports our network, including stopbanks, do the job it was designed to do. It is one of the tools HBRC uses to manage flood risk, support the movement of gravel downstream, and look after the wider river system.

Since 2021, more than 2 million cubic metres of gravel has been removed from Central Hawke’s Bay rivers, with extraction continuing each year as part of HBRC’s river management programme.

And yes – where suitable, some of this gravel can be put to good use. For the Waipawa stopbank upgrade, we plan to extract around 60,000 cubic metres of gravel from the Waipawa River near the township and use it as part of the project.

The Waipawa stopbank upgrade is funded through the North Island Weather Event (NIWE) resilience programme.

Central Government is funding 75.15% of the project, with HBRC funding the remaining 24.85% through rates.