There are Alternatives to the Ruataniwha Dam


In the lowlands of the Otago Peninsula, within the hill streams that flow into the harbour, there are water wheels.  They stand as monuments to what once was, to what ‘functions’ there once were within our society, and – vitally – within our water landscape.

For these water wheels now lie within dry stream-beds, redundant, and could only function now immediately following a rain when the streams flush full.  As the bush was cleared, the wetlands (‘swamps’) removed, the tussock replaced with short English grasses, as soil and organic matter were lost from the land, so the ability of the land to slow and store water steadily reduced, and the streams flowed more intermittently.  And now when they do flow it is with a more extreme pattern of potentially flash-flood and dry bed.  The total water that exits these catchments is probably higher than it once was, but the pattern of flow reduces the resilience to floods.

In the Waitaki Valley, older men of the land recall when the streams whose source was in the upland tussock once ran year round, cool, clear, and flush with koura.  As the tussock was removed the functionality of the stream reduced, whether because of the reduction in rainfall infiltration and soil water storage, or because of the loss of mist and cloud harvesting effects of tussock and other raised vegetation, as argued by Professor Sir Alan Mark, and most famously evident within the Coast Redwoods of California.

Professor Peter Holland from Otago studied the stream flow change of an area of the Canterbury Plains through three aerial photographic surveys taken during summer months from the end of World War II to the 1990s.  During that period, the loss of wetlands, woody vegetation, and soil function led to a reduction in the length of permanently flowing streams, and with it, the loss of value to in-stream ecosystems, stock and community connection, as well as to the resilience of the landscape to flood and drought.

The same pattern of change in land and water function is evident throughout New Zealand, including the drier and stormier Hawke’s Bay where the effects of that loss of function are far more severe, especially for drought.

The leadership of Hawke’s Bay Regional Council is demonstrating no understanding of these complex landscape life-supporting functions – which are its core mandate to protect.  Something has gone wrong. Their obvious industrial ideal sees the landscape as simple: Water falls on the hills, it is shed off the hills and collected by a dam (never mind the functions described above), for distribution to irrigators and the mainstem of the river system for the dilution of pollution. That ideal is insulting environmentally, socially, economically and professionally.

A potential landscape strategy for Hawke’s Bay should meet the environmental goals, as well as the goals of local social and long-term economic vitality that are dependent on these landscape functions.  For that, the council needs to demonstrate an understanding of these functions, and that they have clear goals. They have not.  Nor have they taken the next step, which is to develop a policy framework that encompasses a landscape approach to critical issues relating to water. The only goal that is apparent is that “we need the dam.”  Worse, other potential means are ignored, strategy debate is shut down, and the very functions that we need for a viable future – such as a landscape that actually holds water like a sponge – are degraded in pursuit of a factory landscape.

This is not the way policy development is supposed to occur.  A clear understanding of our social values, as well as the environmental, social and economic functional complexity and interrelationships is required, together with the factors that are likely to impact on our future.  Following that is the development of clear goals (outcomes), a policy framework (resilience to uncertainty), then a number of nested strategies (landscape land & water, social capital, economic focus and infrastructure) that will allow us to achieve our goals within our known constraints and unknown uncertainties.

You can’t do that in one building.  You certainly can’t do that within a hierarchical system where no one thinks except the top dog, whatever their motivations.  You need to embrace the communities that know particular issues, and go in asking questions, not providing answers, even ‘draft’ answers.  Because the answers are out there.  That is the model for policy development within a democracy.  The alternative quickly degrades into a form of authoritarianism.

Yet we hear from commentators that the opponents to the Ruataniwha dam provide no alternatives to the problems of drought and regional prosperity.  This is untrue.  The options have always been there, and they have been argued both within the Regional Council and in more public arenas.  But someone is not asking, and no one is listening.

Here are some alternatives.  First, rebuild our on-farm landscape water and other environmental functions (which are synergistic across land, community and economy).  That involves both retention within soil, and within farm wetland and pond systems.  It involves embracing systems thinking and agro-ecological ideas as argued by the UN’s Olivier de Schutter, the paradigm shift in landscape thinking.

Secondly, community-led local-scale storage systems that are not designed with a corporate seller delivering water to a corporate user without concern for the either the environment or the community.  Opuha is one example of a community-led local-scale model.

And finally, if these options have been exhausted and our landscape functions and values assured, then larger-scale systems are an option, but only if they do not involve a level of commoditisation and over-capitalisation that will result in land aggregation and energy-intensification, leading to less diversity and the effective colonisation, depopulation and environmental degradation of local regions as they have done through time from Ireland to Nebraska.

Chris Perley

An edited version of this article was published in the Hawke’s Bay Today Thursday 26th September, 2013

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5 Responses to There are Alternatives to the Ruataniwha Dam

  1. liz remmerswaal says:

    thanks chris

    the pro dam people and fed farmers often hail the opuha dam as an economic success and saviour of the town

    what do you think? xx

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    • cjkperley says:

      It’s a totally different model than a corporate dam selling water to corporate agribusiness and never mind the rest. They cannot compare it to the Ruataniwha.

      It is they same as Business NZ saying oil&gas development will be great because look at economic success of Norway (which keeps ownership snd invests proceeds strategically), when our oil & gas model is far closer to the other extreme of Nigeria!!! Rip shit & bust and devil take the dissenters.

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  2. Pingback: There are Alternatives to the Ruataniwha Dam | Chris Perley HBRC

  3. Keith says:

    Do you have much information about the changes in HB streams?

    In ‘The History of Hawkes Bay’ by J.G. Wilson, it states that in October 1844 explorers Harrison and Thomas were charged a blanket and six yards of calico to be ferried across the Waimarama stream by waka … also that the Porangahau stream was as wide as the river at Whanganui (!)

    I’d be interested to know why, when and where all that water went to?

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    • cjkperley says:

      Don’t know any facts Keith. Good questions. We’ve all heard about the once navigable Tukituki river up to Waipawa, now a braided system. Was that water volumes or river morphological changes to braids following high country erosion? I don’t know. Grants history of the Hawke’s Bay landscape I think talks about it, but I can’t put my hands on my copy.

      Which leaves first principles, anecdote and hypotheses. Two areas of consideration. 1. rainfall generation by higher covers (tussocks etc.) and forest/woody vegetation. 2. The higher water holding capacity of the wider landscapes (big sponge) could lead to a higher frequency of higher flows. In combination, you could have both more rain, and more sponge effect holding water as potential energy and releasing water as kinetic energy more slowly, ameliorating the pattern of flow.

      I’ve discussed number 2. above, and there is no doubt that forests are very good at holding moisture in the landscape as anyone who has studied forest hydrology can attest. In addition, there is no doubt that covers (whether higher pastoral covers or woodland covers and shelter systems) work the same way that sunken stomata and tomentose (hairy) leaves work by reducing the osmotic gradient between a very wet inner leaf and a very hot dry air beyond. The effect is that water is trapped in a pocket of air between the tomentose, and the plant is more drought resilient. Many plants that have evolved in hot dry conditions have such properties. Land is similar. We know that shelter increases the efficiency of irrigation by reducing evapotranspiration (through reducing wind speed and trapping an air pocket). We know that the higher covers encouraged by Holistic Management and by the browse (woody shrubland incorporated into pastoral systems) examples of Lyndhurst farm in Australia (google them for a pdf pamphlet on their farm) and some of the work of Peter Andrews (also Australian) all suggest that – as a principle – trapping water both in the soils and water bodies and ALSO in the atmosphere above ground, are important principles to adopt in any system that is prone to drought and flood.

      The other potentially high factor in increasing the water holding of landscapes and water flows is large upland wetlands. A colleague I trust came from the Oreti catchment in Southland. The Oreti drains from extensive wetland complexes between Mossburn and Te Anau. He remembers the Oreti when he was a boy (he is now about 70) as always having a high flow. When he returned some years ago, he could walk across it almost in gumboots. He thought it was due to the ‘development’ of the wetlands by Lands & Survey, for ballot farm settlement.

      In our Hawke’s Bay environment, especially within erodible systems, there may be a significant reduction in water holding capacity as a result of erosion of our forest soil mantles of a metre or so to pastoral soils of sometimes 100 mmm. But it’s a complex, and multiple factors are almost certainly involved.

      As to 1. above – rainfall, I was taught that convectional rainfall (i.e. heat –> evaporation –> mid afternoon cooling –> rain – which presupposes moisture is trapped within the system somewhere so it CAN evaporate) is not as dominant in NZ as a cause of rainfall as are frontal and orographic (topographical) sources. More correctly, there was no evidence (we were told) for the former in our temperate climate. But there is no doubt that convectional rainfall is a huge part of tropical forest systems, and lack of evidence is not evidence of lack. And Hawke’s Bay temperatures can easily approach and exceed 30 degrees C and more through 5 months of the year.

      Which raises the question of the effect of deforestation on rainfall patterns. I don’t know the factual figures, but (anecdotally) one old chap who lived in southern Hawke’s Bay said to me that it was ‘common knowledge’ that the rainfall in the district (Weber/Pongaroa/Waione) had declined as the native bush was cleared in the extensive “Bush” from Paihiatua through to Woodville and beyond which went on from late 19th C settlement through to at least the 1930s. I was interested a few years back in tracking down some old records before I left the council beforehand.

      So one hypothesis could be that two things could be more important that we have presumed in the past – 1. the role of forests in retaining moisture within the sub canopy, especially relative to open pastoral systems exposed to the very strong drying effects of the spring equinox northwest winds, and 2. that IF there is moisture retained, THEN convectional patterns could occur, and just because it DOESN’t occur now in a modified systems where short covers now dominate doesn’t mean it it couldn’t have happened significantly in the past when there was more moisture within the landscape because there were more woodlands.

      There are some other things that support this.

      There are photographs of Australia’s rabbit proof fence with clouds over the woodlands, and no clouds over the cropping and pasture (google image “rabbit proof fence clouds” and there is a photograph which I cannot copy or hyperlink here.

      But I do think all this supports the thrust to get our land back to as much of a sponge as we can. Better soil quality (esp. biology), higher pastoral and woodland covers, wetlands, woodlands are all important. Large-scale irrigation thinking is just going to exacerbate the problem and take us downhill faster.

      Best

      Chris Perley

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