Treaty breach on freshwater

Mike Joy summarises his findings in support of Ngāti Raukawa's treaty claim, detailing the New Zealand Crown's failure to act as guardians of the freshwater systems in the lower western North Island.

The poor and deteriorating state of water quality in New Zealand is undeniable. Nationally, nutrient, pathogen, and sediment impacts are worsening, particularly in intensively farmed and urban areas.

Before going further, I want to point out the problems with the term ‘water quality’ as used by Crown agencies in New Zealand. It suggests a comprehensive measurement of freshwater condition and most non experts assume it would encompass many aspects of freshwater habitat and freshwater health and integrity.  The reality, however, is that it is a managerial rather than an ecological assessment or ecosystem health appraisal.  The parameters used to assess water quality are more closely related to ease of sampling than any genuine representation of waterway condition or health. They likely reflect a time three decades or more in the past when they were implemented when freshwater health was seen as of lesser importance than now. For example, a concrete channel could have perfect water quality under this assessment but be uninhabitable for biology because there is no suitable habitat. Problematically, this ‘water quality’ assessment does not assess ecosystem function, habitat quality, mauri or any cultural assessment, and generally not biodiversity.  Notwithstanding those problems they are in-turn exacerbated by the fact that this limited set of measures are collected as one-off ‘snap-shot’ samples, despite it being known that the parameters become progressively more variable as impacts accumulate in freshwater systems.  A good example is the diurnal oxygen variability outlined later in this chapter. In addition to that, most of the other measures of water quality vary seasonally, diurnally, and longitudinally, again with implications for the data sets produced from one-off ‘snap-shot’ samples.

Crucially, the impacts on freshwater biology are often not directly related to the parameters that are measured.  The biological effects are often secondary – for example when nutrients in rivers increase, fish at first are not affected directly (although at very high levels these nutrients are toxic). Over time, however, the ensuing increase in algal growth can lead to extreme fluctuations in oxygen availability.  These extremes (both low and high) are potentially lethal for all stream life, or at least harmful, but because guidelines and measurements are based on ‘snap-shot’ sampling, this diurnal variability is overlooked, and thus the detrimental consequences are generally not apparent to resource managers.

The other ‘water-quality’ parameters – nutrient levels, pH, suspended sediment, and temperature – also vary in degraded systems.  However, unlike oxygen, the changes are not always diurnal but also in relation to flow and biological instream processes.  For example, the bulk of the phosphorus entering flowing systems happen during flood events and both phosphorous and nitrogen levels can vary as these nutrients are taken up and released by instream plant life. Similarly nitrate levels in samples are the residual levels after alga and plants have taken it up. So, you can have a low seemingly healthy nitrate level in the water column sample while algal biomass is at danger levels. Assessing such variability using one-off snap-shot sampling is not scientifically robust, and masks problems including the ones I have outlined above.

Other key indicators of ecological decline are not measured at a national scale, including physical alteration of habitat by deposited sediment. As I will describe later, deposited sediment is a crucial habitat component but is not measured. Also not mentioned or measured is the physical instream engineering of rivers for flood control using heavy machinery and the associated confining of rivers within stop-banks, there is also the loss of habitat to migrating fish and the blockage of up and downstream passage to complete life-cycles caused by dams for hydro-electricity and irrigation.

The data clearly shows there have been significant declines in freshwater biodiversity, habitat and water quality nationally and in the inquiry area.  This plainly reveals a systemic failure by the Crown to protect the freshwaters of New Zealand. There are many symptoms and indicators but one of the most telling is the fact that New Zealand has what is likely to be the highest proportion of ‘threatened’ and ‘at risk’ freshwater fish in the developed world. The fish are in effect the miner’s canaries as they integrate all the processes occurring in waterways.

The environmental degradation in the inquiry area has mirrored that seen nationally but the loss of wetlands has had multiple impacts.  The loss is seen first through the direct loss of fisheries and bird habitat and secondly the loss of the ‘kidneys’ of the freshwater systems.  Wetlands are likened to kidneys because of their ecological functions taking up nutrients, cleaning water and dissipating flood flows. This loss of protection from these ecosystems and allowing the addition of more nutrients through intensification of farming and allowing industrial discharges to water is where the failure of the Crown to protect these values is most obvious.  This has occurred through a litany of failures; including a failure to measure the important and meaningful symptoms of decline and a failure to implement or enforce any meaningful limits to halt declines.

In the full report I make a comprehensive assessment of fisheries and wetland loss. In summary there were three main processes by which the Crown reduced the availability of crucial inland waterway assets - that is wetlands, rivers, lakes and the fishes in them. The first was the consequence of the purchase of land by the Crown, whereby they controlled vast stretches of land alongside waterways, and thus, controlled access to these waterways. The second was the fundamental freshwater community changes brought about by the introduction of exotic fish species, and the initial actions of the organisations representing these fish wanting to remove indigenous eels because of perceived impacts on the introduced fish.  Third was the degradation of waterways permitted and encouraged by the Crown, through a multitude of changes brought about by vegetation clearance, wetland drainage, building towns near rivers so that stop banking is required, and permitting the discharging of municipal and industrial waste into rivers and lakes. More recently, the crown failed to protect freshwaters by allowing unlimited intensification of agriculture with consequent impacts as I noted above.

The examples above starkly reveal the failure of the Crown to protect healthy freshwater ecosystems and the fisheries they supported; the failings are most obvious at the landscape scale change. The extent of landscape and consequent landuse change in the inquiry area since colonisation has been immense.  Nearly all of the natural vegetation habits types have been reduced, 94 percent of the natural vegetation has been removed and, in most cases, replaced with pasture.  Wetlands previously dominated the lowland landscapes especially in the northern half of the inquiry area, and now 98 percent of these have been removed – drained or covered over, and the remaining wetlands are in a poor state.  The value of these lost wetlands is immense and using their ecosystem services economic value to illustrate this the loss is somewhere between 7 and 8.6 billion dollars.   The loss of habitats for fish can also allow for the assessment of the fisheries value and biomass lost. This assessment revealed that somewhere between 9,800 and 180,000 tonnes of eels have been lost.

The draining of wetlands and forest clearance had profound impacts on the value of the natural landscape in the inquiry area to Māori in many ways including the direct loss of habitat as well as the erosion of habitat quality for fish and birds.  After initial destruction of habitat after colonisation, the damage continues to this day through governmental or private development schemes on rivers and lakes including sewage discharges, farming intensification and water abstraction. The loss of habitat for fish occurred on multiple fronts; through the actual physical loss of and through the degradation of waterways and wetlands, then the loss of access to remaining waterways.

  • The full Ngāti Raukawa treaty claim document is available online here.