Continuing TRM’s attempt to answer anglers’ difficult questions about how and why the trout fishing habitat in the mighty Tongariro River has been allowed to deteriorate so far…
During the last 20+ years, TRM have listened to endless complaints from anglers upset at the continual deterioration of the Tongariro River environment. To illustrate the continual mismanagement and to support the explanations, supporting photographic evidence of the deterioration over last 20 years was posted in the TRM blog yesterday. Viewers and anglers’ response has been remarkable. They are far more concerned than most realise.
Anglers complain it has now reached the stage where some suitable form of suitable compensation needs to be assessed. They have suggested it could take the form of extended angler-access tracks or bike trails to open up the upper river beyond its present limits. This would help compensate for the loss of trout habitat and tourist fishing opportunities in the lower river.
The NZ hydro dam story started over one hundred years ago when the demand for power exceeded the importance of trout fishing and the tourism industry. The Arapuni Dam and Power Station (photo above) were built between 1924 and 1929. As the first government-built high dam on the Waikato River, it was commissioned in 1929. The project included the construction of a 64-meter-high dam and a reinforced-concrete powerhouse, a significant engineering feat of its time.
To satisfy the increasing demand from Auckland, Arapuni was followed by others, with a total of eight Waikato River hydro dams, which have the vast majority of the total storage within the Waikato catchment, totalling 570 million m3, equivalent to 16.5 days of the average Waikato flow at Mercer (400 m3/s).
By the 1960’s, work commenced on the last and biggest hydro project of them all. The Tongariro Power Scheme was a major 360 MW hydroelectric project constructed between 1964 and 1983. It diverts water from 36 rivers and streams via 80km of tunnels and canals into Lake Taupō to feed three power stations—Tokaanu (1973), Rangipō (1983), and Mangaio (2008)—which together generate roughly 4% of the country’s electricity. There is no question about the merits of the engineering design, but now the long-term environmental damage and costs are more evident, they need to be independently addressed.
As the Tongariro River is the largest tributary to Lake Taupo, any potential detrimental effects were closely scrutinised. When tested, the Government or MOW (Ministry of Works) and other government departments provided written commitments that the scheme would not negatively affect the Tongariro River, or more broadly the Lake Taupo fishery. They were wrong.
Now, 60 years later, there is ample evidence that severe aggradation, caused by the reduced flow in the Tongariro River, has destroyed much of the lower river spawning environment and a suitable compensation package is due.
A difficulty with any negotiations for habitat compensation is that the Tongariro River management is part of an intertwined scheme involving multiple organisations, e.g., two power companies (that inherited the issues), other management organisations such as the Taupo District Council, the Waikato Regional Council, Environment Waikato, Ngati Tuwharetoa interests, DOC (Department of Conservation) plus fishing clubs and other environmentally aware clubs and organisations that have all suffered.
Even in the Turangi residential zone, the negative aspects of continued aggradation have now been commercially acknowledged, as it threatens the very survival of Turangi, where the Taupo council have designated “Flood Hazard Zones” to recognise future threats. It is time for any responsible council to factor its long-term plan into ensuring that any future expansion of residential development is located outside its flood zone or well away from the established Turangi development.
Recently a Turangi real estate agency promoted property outside of the flood zone – quote: “Positioned in what locals call the ‘Remuera or Oriental Bay of Turangi’, this immaculate executive residence delivers refined comfort in a premium, no-exit setting — quiet, private, and free from through traffic.
Importantly, the home sits above the flood zone (as confirmed by the latest LIM report), offering added peace of mind.“
In case you imagine this is all fiction from TRM’s fertile imagination, we refer to: “Fishing the Tongariro” by Grant Henderson 2023, Chapter 19 – Page 226.
Tongariro will never be the same, Nature Council regrets
– from The Evening Post, 24 September 1964.
Quote: “Even before construction began on the Tongariro Power development works, it was clear that the trout fishery would be affected to some degree and that those changes – mostly in the form of reduced river flow – would be permanent.”
In 1964 the government MOW (Ministry of Works) was convinced that the scheme was essential to NZ’s energy needs. The reaction from various acclimatisation societies and fishing clubs was more honest. and accurate. The official consultants, Sir Alexander Gibbs and partners, advised of the need for a comprehensive statement on the fisheries aspect, but the views from Internal Affairs and the Marine Department were kept confidential.
An earlier 1958 confidential brief from the Marine Department advised that the demand for electricity was not, in terms of growth, any more remarkable than the increase in demand for angling, and that it was imperative that the new hydroelectric proposal should be integrated with, rather than developed at the expense of, freshwater fishing.
In 1960, the government was informed that the Tongario diversion was unacceptable. To the maximum extent possible, the two needs had to be reconciled, although that was impossible. The differences were clearly irreconcilable.
Had the RMA (Resource Management Act) been applicable back then, the scheme would never have received approval. Unfortunately, as the decision was made by other government advisors, from the Internal Affairs Wildlife Branch to the Marine Department, it could not be relied on, as they were government employees, not independent advisors.
The same unfortunate situation continues today, as the government department – DOC – is the Taupo Fishery’s manager, who naturally has to give weight to political employment policy considerations rather than to anglers’ spawning environment and access needs. That is understandable.
Back in 1989, the Taupo Area Fishery Manager, John Gibbs, advised in his submission in the flow management survey that reduced flows in the lower Tongariro reaches would result in less rearing habitat for juvenile trout. He noted: “Instead of the challenge of a large, boisterous, unique river demanding a special approach and techniques, anglers are now faced with a smaller, tamer river, much more like those they can fish elsewhere in the country, or indeed elsewhere in the world.”
Later, other DOC employees, such as Glenn MacLean, also publicly expressed their views when the resource consents granted to Genesis Power Ltd. for the operation of the scheme were up for renewal. MacLean and others provided evidence of a decline in anglers’ catch rates since the power scheme began, asserting that reduced flows adversely affected rearing habitat for juvenile trout.
Since then, the lower river habitat has continued to deteriorate and is now far worse than it was over 25 years ago. It is embarrassing to take tourist anglers down there.
Anglers believe it is time for a new, completely independent enquiry.
The health of the Tongariro River is the responsibility of Waikato Regional Council. They have failed tourist anglers. Their head office is located in Hamilton, about 200 km north.
Previous compensation precedents for the loss of recreational activities provided by a wild and scenic river were negotiated with Genesis Energy Ltd., the operator of the power scheme. It is time they were formally approached again, with the aim of replacing the lost spawning, fishing and access opportunities in the lower river by extending the Tongariro River Trail to link with the Poutu Dam access. This needs to be a loop track along the high banks on both sides of the river, suitable as a tourist bike trail, with several side tracks to pools for anglers.
Before NZ Electricity was carved up to form Genesis, they provided many of the recreational facilities in Turangi. They were not insignificant. They had obviously done their sums and realised they benefited more from goodwill as compensation for the environmental damage caused by the hydro power scheme. That was over 50 years ago. Since then, Genesis appears more concerned with the $ return to shareholders, including the Crown, than with continuing to spread that valuable goodwill to the next generation.
