Why does The Wairarapa need water storage?

Bleak climate change report

In August last year, the Greater Wellington Regional Council (GWRC) declared a climate emergency and stated that Climate Change is one of the region’s biggest challenges.

This was on the back of a NIWA commissioned report in 2017 that described significant impact for the Wairarapa:

  • The Wairarapa will experience a significant increase in hot days
  • Frosts in the high elevations of the Tararua Ranges is likely to disappear
  • Spring rainfall will reduce by up to 15% in eastern areas
  • The risk of drought will increase in the Wairarapa

The GWRC said: “We’re thinking about the future of our natural resources, and have been working with the people of our region to create action that will safeguard our region’s resources for future generations.” This project is part of this.

Regional development

In 2018 the three Wairarapa Councils got together to develop the 2019 Wairarapa Economic Development Strategy and Action Plan - it identified water shortages as a major cause for concern. It stated that “shortage of water in the summer season is a whole-of-community issue” and that “greater water reliability is needed if the region’s economy is to diversify, never mind grow”. Without resiliency of water supply there will be significant flow on effects to the economy and wellbeing of our communities, given these are some of the region’s largest employers.

Water quality

In order to protect the rivers in the Wairarapa, less water will be allowed to be extracted for farming and towns. Limiting access to water in the Ruamāhanga catchment presents significant risk to the viability of many rural and industry operations that rely on reliable water for productivity. Under the proposed GWRC Natural Resources Plan, Category A groundwater users will face a complete cease take when rivers drop below minimum flow levels.

Water needs

Water supply concerns are also highlighted in the GWRC Reframing Investigations Report completed in 2018. It finds that water supplies are under pressure due to a growing population and decreasing rainfall and river flows.


The Wairarapa will see increased demand for water due to climate change pressures, rising environmental standards, a growing population, to enable change to low carbon farming and grow industry for jobs. In addition, access to reliable water, which is proven to support economic growth, will be particularly relevant for recovery post COVID-19.

Capturing excess water in high flows in the Wakamoekau reservoir will help provide the water the region will need.