Better water quality won’t happen overnight … but it must happen

By Waiology 18/12/2013

By Jenny Webster-Brown

Un-muddying the Waters : Waiology : Oct-Dec 2013If we cannot stop ongoing water quality degradation, and effectively restore degraded water environments, we stand to lose much that we value about New Zealand and our way of life. We will lose recreational opportunities, fisheries and our reputation for primary produce from a “clean” environment. We will lose functioning ecosystems, the ecosystem services they provide and the beauty of our iconic water features. We will have to pay for increasingly higher technology to treat drinking, stock and even irrigation water … like so many drier, more populous or older nations, who have long since lost their natural water amenities. This is not what we have known, or what we wish for our children, or their children. To improve water quality, we need only three things: the will, the means and the time.

This is the final invited article in this Waiology series on aspects of water quality. On the basis of the preceding articles, augmented by my own experience as a water quality scientist, I would like to reflect on where we currently stand with respect to these three requirements. A ‘will’ to improve water quality is clearly evident. Over the last 5 years we have seen an unprecedented level of activity from national government seeking to change NZ’s freshwater management policy, via various primary industry initiatives, the broad, consensus-based Land and Water Forum and the ‘Fresh Start for Freshwater’ programme. A greater role for community decision-making in setting water quality targets for local catchments is a key component of the Freshwater Reforms.

A Lincoln University research student measuring changes in water quality parameters over a 24 hr period in Lake Ellesmere/Te Waihora,  to understand how this large shallow lake responds to catchment land use.  (Photo: J. Webster-Brown)
A Lincoln University research student measuring changes in water quality parameters over a 24 hr period in Lake Ellesmere/Te Waihora, to understand how this large shallow lake responds to catchment land use. (Photo: J. Webster-Brown)

The ‘means’ include the new National Policy Statement for Freshwater Management, highlighted in two of the Waiology articles (1, 2), and its recent amendment to include a more prescriptive National Objectives Framework (NOF). However, the devil is, as always, in the detail. The devil, in this case, is in the science information that underpins this new policy. Water quality degradation is a classic “wicked problem”, with multiple contributing factors, unexpected interactions and often inexplicable environmental responses. The Waiology blog has included articles by some of NZ’s top freshwater scientists, conveying their understanding of the cause and effects of the ongoing water quality decline; causes such as urban stormwater drainage and agricultural activities, and effects as manifested in surface freshwaters, ground waters and estuaries. The authors have also often noted the limits of their current understanding, the difficulties imposed by insufficient data, and how this creates uncertainty in predicted outcomes. This same uncertainty can lead to disagreement amongst scientists asked for comment or advice, as it has with the setting of numerical ‘attribute states’ in the NOF, for example.

To quote author Sheldon Kopp … ‘All important decisions must be made on the basis of insufficient data’. Although robust scientific debate is considered a healthy way to get at the truth in the world of science, it is not particularly helpful to policy makers or to the communities tasked with making decisions about the value of a water body. So how can scientists best support the immediate needs of this brave new world of freshwater management? While acknowledging the need for better data and information about water environments, we can try to communicate the concepts and facts that we do have confidence in, as simply as possible and without contradiction. We can help the policy-writers formulate straightforward, practical policies. Recent freshwater management policy introduces increasingly unfamiliar terminology and complex application principles. In the field of water quality science, there are many examples of simpler guidelines and standards taking precedence over more rigorous, but difficult to use, alternatives.

Scientists can help to manage expectations, by providing guidance on realistic targets for water quality and being honest about likely timescales for change. Which brings us to ‘time’. Even if every positive action taken has the anticipated positive effect, improvements in water quality will not be immediate or perhaps, in some cases, even detectable within our lifetimes. This is just the beginning of a critical time for NZ water quality and good things, in the words of Mainland Cheese, do take time. More reliable predictions of future conditions will be critical during this period to reassure those who grow impatient, that change won’t happen overnight … but it will happen.

Professor Jenny Webster-Brown is a water quality chemist, and the Director of the Waterways Centre for Freshwater Management at the universities of Canterbury and Lincoln.

0 Responses to “Better water quality won’t happen overnight … but it must happen”

  • Science lacks yet industries are targeted, bullied an undermined by politicians. The ‘dirty dairy’ campaign seems to have undergone a revival.

    In the mean time Globalisation provides us with a platform to prostrate ourselves in a self deprecating manner.$114-000-fine-for-nz-based

    Environmental science is the only biological science where I regularly hear “insufficient data” as a broad sweeping caveat . I’m guessing political lobbying behaviour has necessitated such disclaimers? Perhaps it is simply underfunding has not facilitated good data? I think the former reason is more likely.

    Further pressure must come from the use of rhetoric and populist statements similar to those contained within the introductory paragraph of this article.

    The opening paragraph for example:
    “If we cannot stop ongoing water quality degradation, and effectively restore degraded water environments, we stand to lose much that we value about New Zealand and our way of life”

    This sweeping statement ignores the fact that science suggests New Zealand has been improving in most of the significant water/river contaminants.

    I would like to take this opportunity to encourage Professor Jenny to consider the possibility that improvements are being made, as the Ministry for the Environment has put it.

    Accepting this likelihood, will help to focus efforts collecting sufficient data, to help NZ make gains in the apparent and most significant problem – Nitrate. Undeniable evidence is more likely to elicit an undeniable response.

  • In case you’re not aware, and given your concern with models, I should point out that the results presented in that MfE bar chart, which is only concerned with streams and rivers, are modelled. (They are modelled to provide a balanced assessment across NZ, rather than being spatially biased by density and locations of finite monitoring sites.) [DC]

  • Very aware Dr,
    No doubt you’ll observed my use of the phrases – “suggests”, “possibility”, “likelihood”

    Compare this to Dr Jan’s statement referring to her findings
    “this investigation has shown the clear link between expanding dairy farming and increasing stress on water quality”

    Clear??? Is that what models show? Clarity?

    I also have issue with one of the media articles that says “damning” I don’t think Dr Jan’s model shows that. Perhaps they used that word because Dr Jan used “clear'” ? Who knows?

  • Not true. I’ve cast doubt on both the models I’ve referred to.

    I’m sure you will agree the terms “suggests”, “possibility”, “likelihood” contain doubt.

  • Mr E,
    You suggest that the fact that environmental science research is often foiled by ‘a need for more data’ as being a political line. This is not true. Unlike other biological sciences such as genetics and physiology, environmental science (i.e. ecology) is inherently difficult to study in the laboratory. This is why researchers are often demanding more data. Out in the field there are a multitude of complex interactions simultaneously occurring at once; and unlike in the laboratory, you cannot eliminate variability caused by these. This is why far more complex statistical models are needed to analyse data and also why these models require so many observations to demonstrate statistically significant data. This is also why many researchers are hesitant about giving absolute answers… it’s a conservative statistical practice!
    Generally there is very robust, conclusive correlative data demonstrating the link between land use and water quality, it is just VERY difficult to show a mechanistic pathway linking the two.
    Here, Jenny Webster-Brown says that researchers need to focus on the consensus within the research. That is what Jenny has done here and it presents a conclusive picture of the state of NZ’s waterways (not improving as the MfE report suggests)Leave your comment here…

  • Just a question (or two) for you Simon S. How can a researcher draw quantitative empirical conclusions if they cannot, as you have said, isolate the variables? Wouldn’t the research have to identify the variables clearly in order to rule out a null hypothesis?

    Until this has been done, wouldn’t data from studies be best regarded as qualitative? In the interim there is always going to be a requirement for more data. This is not political, it is necessary in order to form testable hypotheses, ie. ones in which the variables can be isolated. Where it maybe gets political, I think, is where claims of “proof” are made far to early and for practical expedience.

  • I’d say that scientists everywhere want more data. It just happens that the data they want evolves as they incrementally fill knowledge gaps. But these gaps are never 100% filled – there is always uncertainty, and sometimes societal decisions are made when the gaps are not even close to 100% filled.

    It is the uncertainty that can be, and is at times, exploited for political ends. Or simply because the policy consequences of accepting a scientific result puts someone at a disadvantage.

    Naomi Oreskes writes about this in ‘Merchants of Doubt’, regarding climate change, but there are cases all over environmental science, and outside.

    On the other hand, there are times when people ignore the uncertainty in order to support their interests. And in fact, I find it interesting when one group overplays the scientific uncertainty in X while downplaying it in Y. Not easy to find examples of this just in freshwater, and in NZ, but across contentious issues.

    So, “need more data” is not necessarily a political line, but it has been at times. [DC]

  • I agree with your comments regarding uncertainty. The more politicised an issue becomes the more pressure there seems to be to prove models (in particular) to be correct. This creates an opportunity for more errors to creep in. The errors eventually become obvious and in turn are exploited and it is a downward spiral from there. ‘More data’ is called for, but won’t fix things. Then somewhere in the mix are those practical people who just don’t want to waste time and other resources following advice that doesn’t work, or alternatively, working on problems that are too big to make a dent in.