The Heretaunga Water Storage Project
There is a growing gap between Hawke’s Bay’s demand for water and the environment’s ability to reliably supply it. This gap between supply and demand is likely to be exacerbated by the impacts of a changing climate. (Read the HBRC Climate Change Risk Assessment reports here.)
Without a structural intervention to improve water security, the Heretaunga Plains - Hawke’s Bay’s economic engine and one of New Zealand’s most productive and important food-growing areas - faces reduced reliability, stalled development, constrained iwi economic participation, and ecological decline.
The Heretaunga Water Storage Project is investigating the feasibility of building a storage reservoir on a small tributory to the Ngaruroro River on farmland at Whanawhana. The reservoir would hold 27 million cubic metres of water (27 billion litres), harvesting peak winter flows and storing them for release into the Ngaruroro River and Heretaunga’s lowland streams during the summer months of peak water demand.
This additional water would offset the environmental impacts of summer groundwater extraction, supplementing flows in the Ngaruroro River and lowland streams, and support the natural recharge of the Heretaunga aquifer.
This short video of the proposed site shows its proximity to the Ngaruroro River which it will supplement in summer.
At this scale, the proposal would not only support Heretaunga’s natural environment and existing businesses and communities, but could unlock additional water supply for the region’s economic growth. The population is projected to grow and unlocking access to new water represents an important opportunity to ensure more equitable access to water.
The benefits of a more secure water supply would benefit all residents of the Heretaunga region. The costs of the development would be met by those who benefit most from the water, primarily irrigators and industrial / commercial water users.
The proposed scheme is located at the top of the Heretaunga catchment, ensuring the stored water remains within its original catchment. The proposed reservoir is designed as a dedicated local solution to Heretaunga’s water security challenges; it does not seek to address water security challenges in other parts of Hawke’s Bay.
Hawke’s Bay Regional Water Assessment
The regional approach to water security is informed by a comprehensive Regional Water Assessment, including detailed analysis of regional supply and demand, that was completed by Hawke’s Bay Regional Council in 2023.
This is an important piece of work, jointly funded by HBRC and Kānoa, upon which future decisions around the region’s water security can be based. For people looking to understand Hawke’s Bay’s dependence on secure supplies of freshwater, including a breakdown as to how we use our current resources and how a changing climate may impact supply, this is important background.
Read the full Regional Water Assessment here and some shorter FAQs here.
Water security must start with efficiency, but the ability to increase supply is also essential. If we rely exclusively on water conservation, we run the risk of pitting industries, businesses, and communities against each other in competition for a scarce and, at times unreliable, resource.
Community-scale water storage options provide opportunity for more equitable access to freshwater across our communities.
The feasibility phase examines the option of water storage for Heretaunga at the Whanawhana site. It will provide robust data to enable decision making. If the decision is made to proceed with storage as part of Heretaunga’s future water security strategy, it must be developed alongside a strong commitment to using the water we already have more efficiently.
There is a lot of work across the region to reduce waste and more efficiently use water. We fully support this. Reducing waste must be where we all start in better protecting our water resources. Both Napier and Hastings Councils have committed to significant efficiency measures.
Irrigators are harnessing new technology to better understand precisely when and how to irrigate and to use water most effectively. Sharing of water across the growing community is now occuring to ensure water isn’t wasted and that it is used where it is most needed.
Water efficiency is a core part of our shared commitment to water security and there is a comprehensive region-wide programme of work under way to dramatically improve how we use water.