Wakamoekau Community Water Storage Scheme

Wairarapa Water is currently working on the Wakamoekau Community Water Storage Scheme (WCWSS).

Wakamoekau is about doing water storage in a different way. By this we mean that community water storage has shared positive outcomes. It is about protecting Wairarapa communities – socially, environmentally and economically – where environmental benefits as well as cultural considerations are as important as economic ones.

The proposal is off-river water storage which only captures excess water with no negative impacts on surrounding waterways. The water will provide for rivers, towns, industry, land-use change, and rural supply.

Wakamoekau is part of the solution for protecting communities and ensuring the health of our catchments. It has been investigated in detail and is progressing well with wide support from a diverse group, including our Government.

We are working with a wide range of groups including Wairarapa Iwi, landowners, businesses and Councils, and are aligning with the Ruamāhanga Whaitua Implementation Plan.

Because Wakamoekau has been put forward as an option to benefit the Wairarapa, hearing from the region’s communities and stakeholders is critical. Please see our contact information to get in touch.

This project has already had significant investment work, over 12 years by multiple parties, including the current and previous government as well as GWRC. With the combined research, knowledge and energy of all these parties, now is the time to get it delivered if practicably possible.

What we are proposing

The project involves construction of a reservoir, in the hills north west of Masterton, with a capacity of nearly 19 million cubic metres of stored water. The reservoir will be capable of supplying 28 M m3 of water per annum at greater than 90% reliability.

Water will be collected from the Waingawa River and Wakamoekau Stream catchment during periods of high flow. Stored water will be distributed as far as economically and technically possible, including South Wairarapa if viable.

The current estimate for construction cost is $100 - $120 million. The project is regarded as small-scale in size and scope.

An illustration of the proposed reservoir located in the hills north west of Masterton.

We recognise that ensuring the Wairarapa’s resilience as we face climate change challenges is complex and that a number of options, including possible nature-based ones, are being explored. That is why a Wairarapa Water Resilience Committee for the region has been established, and we are working closely with it.


The reasons why the Wakamoekau has been developed and supported by central and local government, Iwi, farmers and industry is described in the Why does The Wairarapa need water storage? section of the website. In essence, various scientific and economic reports determine that the Wairarapa will see increased demand for water due to climate change pressures, rising environmental standards, a growing population, and requirements for water to support a change to low carbon farming and grow industry for jobs post COVID.

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

The benefits that water will provide have been determined as follows:

  • Increased water security for towns, rivers, industry and rural supply;
  • Reliable water from the Wakamoekau will support industry and farming and can bring jobs to the Wairarapa in a post-Covid New Zealand;
  • Securing and creating employment opportunities pre-, during and post-construction activities;
  • Incorporating iwi and environmental aspirations as set out by agreed funding principles with government;
  • Optimising environmental flows in rivers through releasing stored water;
  • Environmental management plans for water users driving behavioural change and adaptive management of environmental limits as knowledge increases;
  • Mapping out ways to help water users change to higher value, non-intensive land use;
  • Providing reliable water that will allow access to the increased choice of crop created by a changing climate;
  • Potential to address emerging issues with the three District Council’s municipal water supplies, ageing stock water race infrastructure, water quality in Henley Lake, Queen Elizabeth Park’s Lake of Remembrance and other waterways.


  • The Consenting and Procurement phase could kick off in late 2020.
  • If all necessary consents can be obtained, construction could start in 2023.
  • Scheme (reservoir and piped network) would be operational by 2026.

Making It Happen