Climate change is driving a growing gap between water demand and supply in Hawke’s Bay, according to a new report on the region’s water usage.
Jointly funded by Kānoa – Regional Economic Development and Investment Unit and Hawke’s Bay Regional Council, the Regional Water Assessment (RWA) investigates how much water the region currently has, how it’s used, and what that will look like in future.
Regional Council Chair, Hinewai Ormsby says Council has shared the report with Treaty partners, mayors and stakeholders this week ahead of a wider release of the document in the New Year.
“The report highlights that our waterways have no more to give, while at the same time pressure on our water supplies is only set to increase as our community and economy grows,” she said.
“In the past, we’ve treated natural resources, including water, as if they were practically endless but we now know that’s not the case. Climate change and increasing demand are putting our future water security at further risk.”
Regional Water Security Programme Director, Tom Skerman says it is the first time a Regional Council in New Zealand has completed a region-wide stock take of its water supply and demand to inform decisions about how to better manage water in the future.
“The report focused on the July 2019 to June 2020 year. We found that at the start of the year, 10.2 billion cubic metres (Bm3) of water was held across all water sources in the region, and over the year 13.9Bm3 was carried by our rivers, with more than 16Bm3 of rain falling on our region,” says Mr Skerman.
“On the surface of it we have a lot of freshwater flowing through our region, but we don’t have enough water at the time when it’s needed – in the heart of our increasingly dry summers.”
In 2019/20 Hawke’s Bay used 138 million cubic metres (Mm3) of water, with 64% being used by agriculture, 19% for households, and 13% for manufacturing and processing.
The report, based on leading-edge research, then forecasts future gaps between supply and demand by modelling scenarios based on current demand, climate change projections, and economic forecasts.
“The scenarios tell us that if Hawke’s Bay doesn’t change its water use behaviour at all, our region will face a potential shortfall of nearly 115Mm3 by 2060. Even if we implement significant water savings and efficiencies, we will need nearly 25Mm3 more water by 2040, increasing to 33Mm3 by 2060.”
“This will have consequences right across the community, from lower water levels in rivers and flow on impacts to biodiversity, to less economic productivity and increasingly inequitable access to freshwater.”
The report provides practical options for sustainably managing freshwater that the community can discuss through the Regional Council’s Kotahi Plan engagement process over the next few years.
“Options include reducing rural demand through irrigation efficiency and agriculture conservation, while our urban communities can focus on reducing the demand on the public supply through conservation campaigns, water efficiency, and the option of water metering. The report also highlights the use of water pricing as an additional option to manage demand.”
The report also looks into how we can slow water down, or hold more water in the environment for longer, through wetland protection, improved farming practices and water storage.
Chair Ormsby says the report is a new reference point for discussion on how the region will give effect to Central Government’s freshwater principle, Te Mana o te Wai, which prioritises the health of the water first, then water for human health before other uses, such as the economy.
“If mana whenua, water users and the community come together now, Hawke’s Bay can plan for the future it wants. We simply need to strike a sensible balance between reducing demand and increasing supply to ensure Hawke’s Bay has long-term, climate-resilient, and secure supplies of freshwater, for all,” said Chair Ormsby.
The full report will be released publicly in February, following presentations to Regional Council governors and key stakeholders. Alongside this, the Regional Council will release a summary document of the report and an education campaign to increase awareness of water security issues.
For further information, please see the document Regional Water Assessment – key take outs https://www.hbrc.govt.nz/assets/Document-Library/Water/Regional-Water-Assessment-media-brief.pdf