The Project

What is the Waitaha Hydro Project?

The Waitaha River stretches from its headwaters in the Southern Alps which fall 36 kilometres to join the Tasman Sea on the South Island’s West Coast.

The mouth of the Waitaha River is about 36 kilometres south of Hokitika.

Westpower, in commercial partnership with local iwi, Poutini Ngāi Tahu, are proposing to build a run-of-river hydro project, which – if built – would generate enough power for 12,000 homes and become New Zealand’s newest addition to the hydroelectricity supply which in 2022 provided about 60% of New Zealand’s electricity[1].

Why does New Zealand need more renewable electricity?

New Zealand has committed to reach net-zero carbon dioxide emissions by 2050[2]. To do this, substantially more renewable electricity will be needed. About 15%-20% of electricity in New Zealand comes from fossil fuel (gas or coal)[3], with the remainder coming from renewable sources.

But decarbonising means going so much further than getting to 100% renewable electricity.

In the wider energy sector (where petrol and diesel are used for transport, coal and gas are used directly for manufacturing and space heating) it’s a much bigger challenge. About 60% of New Zealand’s wider energy supply comes from fossil fuels[4].

Cutting emissions from how people and goods move around the country and around the world, how things are made, kept warm, kept cold – everything, effectively, that uses energy – means increasing the country’s renewable electricity supply.

Transpower, the state owned enterprise which owns, maintains, and operates the national grid, predicts that at the base case electricity supply in New Zealand will need to increase by about 70% by 2050 to meet the needs of decarbonisation[5]. Earlier predictions have estimated an increase of 100%[6].

New Zealand electricity supply by source 2022

Projected electricity demand growth, Transpower

What would the Waitaha do for electricity supply and emissions reductions?

In 2022 customers in the Westpower generation area (Grey District and Westland District on the West Coast) used 218 GWh of electricity. With Waitaha’s annual estimated output between 110-120 GWh, it could supply up to half of the electricity needed in the region. This would also reduce transmission losses which occur when electricity is imported to the West Coast from Canterbury and elsewhere.

In reducing the need for fossil fuel powered generation (from coal and gas), Westpower estimates the emissions reductions achieved would be between 65,340 and 119,460 tonnes of CO2 per year, about the equivalent of taking between 24,502 and 44,797 cars off of the road.

How would it work?

As a run-of-river hydro scheme no dam would be constructed on the Waitaha river – meaning no inundation or flooding of the valley and no lake above the intake.

Above the Morgan Gorge (which separates the lower Waitaha River and the upper Waitaha River) a weir would divert most of the river’s flow through a tunnel, generating electricity as it spins through turbines at a powerhouse 2.6 kilometres downstream from the intake, before returning to the Waitaha River and flowing out to the mouth into the Tasman Sea.

Slide through the photographs and simulations to see what the Waitaha hydro scheme would look like if established.

Why has this project not been built?

Westpower and Poutini Ngāi Tahu wish to turn this proposal for a hydro scheme into a reality but have been unable to obtain the approval of the Minister of Conservation.

The planning of this development began about 2005, and discussions with Department of Conservation staff began about 2012.

In 2016, the Deputy Director-General (the Minister’s delegate) notified an “intention to grant” the application for the concession, subject to public consultation and a hearing process.

After public consultation and hearings in late 2016, in which 3,264 submissions were received (2,864 or 87.7% of which were template submissions from Forest and Bird), advice by way of a briefing was delivered to David Parker (Minister for the Environment acting on behalf of the Minister of Conservation as decision-maker) for him to make his decision under the Conservation Act 1987.

In August 2019 David Parker’s office announced that the application had been declined.

Why did the decision maker decline the application?

In rejecting the application David Parker noted that he was satisfied the effects on “birds, bats, lizards, invertebrates, vegetation, native fish, and other aquatic communities, sediment, and river morphology will be minor”[7].

In essence, David Parker’s decision to reject the proposal was due to what were determined to be impacts on the “natural character” of the river and impacts on recreational opportunities[8].

Parker noted the access for trampers and hunters would likely improve as a result of a better access road near the track and improved access into the Waitaha Valley via track upgrades as a result of concessions being granted[9].

David Parker’s decision with regard to recreational values focussed on kayaking.

Westpower estimates that about 50 kayakers per year utilise at least part of the 36 kilometre Waitaha River – an estimate DOC staff considered this to be a “fair assessment” but put an estimate of 50-100 kayakers per year due to an estimate from WhitewaterNZ of 100 users per year[10].

The area impacted by the proposed hydro scheme (about 2.6 kilometres from the water diversion above the Morgan Gorge to the powerhouse below the gorge) is however incredibly dangerous and can only be kayaked by a very limited number of kayakers.

For instance, Westpower estimates from 2002-2015, about 7 attempts (not all of which were successful) were made at kayaking the Morgan Gorge over the 13 year period[11].

This equates to about once every two years, with the first successful kayaking of the Morgan Gorge taking place in 2010.

Westpower, in its initial application, offered two days per year when no water would be taken or diverted so water could flow through the Morgan Gorge in its natural state – this has since been increased to four days per year[12].

David Parker acknowledged the dangers of kayaking the Morgan Gorge but noted in his decision the small number of “extreme kayakers”[13] who kayak the gorge.

Parker said in light of the submissions (received through the public feedback process) that “it appears incontrovertible that the river is the apex of whitewater kayaking in New Zealand”.

Westpower pointed out in its application that there are fifty-eight river runs for kayakers on the West Coast[14]. Of these, the Waitaha River is one of 14 “grade 5” runs with helicopter access in the region. Overall, “grade 5” and “grade 4” runs were identified as the most common kayaking opportunities in the region – 24 “grade 5” and fourteen “grade 4” runs respectively.

In its advice prior to the hearing, the Department of Conservation said, “the proposed Waitaha hydro scheme will impact on kayakers ability to paddle the Morgan Gorge and the stretch of the river below the Gorge to Douglas Creek, which is the location of the tail race where water would be returned to the Waitaha River.”

In the same advice, the Department of Conservation agreed with Westpower’s conclusion that measures can be taken to reduce the scale of effects on kayaking (through no take days) but that the change from a river in its natural state means the final effect on kayaking on the Waitaha River remains “high”.

In recognition of the potential impact of the proposed hydro scheme for kayakers, Westpower has proposed the establishment of a Trust with local outdoor educational specialist Tai Poutini Polytechnic.

The purpose of the Trust would be for promoting and enhancing kayaking on the West Coast, through the provision of funds to the local kayaking community to assist kayakers of varying ages and abilities (from beginners through to elite kayakers) with their kayaking needs.

As well as being a partnership between Westpower and Tai Poutini Polytechnic, Westpower proposes that the Trust also involve the kayaking community.

The objectives of the Trust would include[15]:

  • Working with Tai Poutini Polytechnic and schools to promote kayaking as part of education, including tertiary education;
  • Working with kayaking organisations, community groups, iwi and the tourism industry to promote kayaking; and
  • Supporting ongoing kayaking activities on West Coast rivers and lakes, including the Waitaha River.


Westpower has indicated that it would establish the Trust and make an initial contribution of $250,000, and that the Trust could distribute these funds through grants of up to $20,000 per annum to cover activities such as, for example[16]:

  • The purchase of kayaks and other equipment for Tai Poutini Polytechnic and schools;
  • School holiday and community programmes;
  • Refresher courses and health and safety courses relating to kayaking;
  • Targeted funding to support kayaking trips (for example, for more advanced kayakers to access more challenging rivers such as the Waitaha River); and
  • The promotion of kayaking as a tourism activity on the West Coast.


Westpower proposes that the Trust be established once all RMA consents and concessions are in place.

What’s next?

In May 2022 Westpower wrote to the Minister of Conservation, Kiritapu Allan, asking for a formal reconsideration of the application for the hydro scheme. Since then there have been two different conservation ministers – Poto Williams and now Willow Jean-Prime.

The request is still with the office of the Minister of Conservation on the following grounds:

  1. Section 4 of the Conservation Act, the Treaty principles, and the views and aspirations of Poutini Ngāi Tahu (a partner in the project).
  2. The climate change emergency and the need for these types of renewable energy generation projects to be authorised including on public conservation land (noting the significant impacts of climate change on biodiversity and conservation land and resources).
  3. The need for a real-world and contextual assessment of the effects of the project on values such as natural character and tramping, including an assessment of recent refinements that significantly reduce the visibility of the project structures.
  4. The assessment of legal and planning matters.


Westpower has yet to receive any response from the Minister of Conservation as to whether the application will be reconsidered or not since the request was made on the 31st of May 2022.