A report that aims to provide scientific context for the divisive issue of water quality in New Zealand is being launched by Parliamentary Commissioner for the Environment (PCE) Jan Wright at an event in Wellington today (20 March).
In the report, the PCE states: “Water quality is a subject of high public concern and vigorous debate. However the science of water quality is very complex, and much of the information required to understand it is highly technical.”
To address this, she has produced a plain-language summary of the issue that considers the historical context of land use changes and water quality issues, before breaking down the topic into a discussion of water-borne diseases, sediment and excess nutrients (i.e. nitrogen and phosphorus). It also includes a case study of the Manawatu River.
A full copy of the report is be available on the PCE’s website .
You can listen to audio of Jan Wright speaking at the release of the report below (from 20 Mar 2012):
The Science Media Centre contacted experts in water quality and freshwater science for reaction to the report. To follow up with these or other experts, contact the SMC on (04) 499 5476, email@example.com
NB: Comments below are abridged. Full commentary can be accessed via links to the PDF files below.
Dr Clive Howard-Williams, Chief Scientist – Freshwater & Coasts, National Institute of Water and Atmospheric Research (NIWA) comments:
“This is a good report that covers the basics of the science and is admirably concise.
“I agree with the decision to focus on the big 3 contaminants (pathogens, sediment, nutrients). If you were to ask me which of the big 3 was the single most important, I would say sediment. Get sediment right and dealing with a lot of the other problems would be made easier.
“To quote the report: ‘Every year more than 200 million tonnes of sediment washes down New Zealand rivers into the sea. This soil is lost forever’. Remember this is mostly top soil. This makes it even worse.
“‘Focus attention at the catchment level’ is another key message that I support.
“Additionally, the discussion of historical context in the report is fundamental to understanding where we are now. You cannot blame councils for a 150 year legacy of bad management.
“What is the next step? Although I agree with the Parliamentary Commissioner for the Environment (PCE) that scientists cannot set community values, science does need to interact more with governance and policy to answer the big ticket items.
“If, for example, there were to be national over-arching objectives for freshwater, such as having Regional Councils set regional pollution reduction targets (examples might be to ‘reduce sediment loads to the coast by 10% by 2025’ or ‘increase the recreational use of the region’s lowland rivers so that 80% are swimmable by 2025’), then how could science contribute to make this happen?
“To use the PCE’s view of what science does, we can contribute by:
- Measuring the different parameters of water quality
- Understanding the causes of change in those parameters
- Designing interventions that are likely to be effective
- Measuring the effectiveness of those interventions and then making sure that these processes are done in a way that maximises the contact between scientists and the regulators and managers.”
Prof Jenny Webster-Brown, Director – Waterways Centre for Freshwater Management, University of Canterbury & Lincoln University, comments:
“[This report] is largely based on the Commissioner’s own recent learning curve on water quality, and written in a casual, very readable style to educate those “engaged in and concerned about” NZ water quality problems.
“The danger with any attempt to simplify a complex subject is always that this can lead to incomplete or inaccurate coverage, and unintentionally mislead the audience it seeks to educate. This occurs in at least three ways here;
“For example, from the title, this report aims to cover “Water Quality in New Zealand”, but actually describes only three components of concern; pathogens, sediments and nutrients. While these are indeed important, they are by no means our only water quality problems, and they are certainly not the most important in an urban environment. In the cities and large towns in which most of our population reside and industries operate, heavy metals, hydrocarbons and other urban contaminants are a major problem. Perhaps the report could be considered the first in a series?”
[See full comments for further point-by-point analysis]
“These points are not raised to discredit the report in any way, but to illustrate the difficulty of trying to simplify the science of water quality to this extent. Those engaged in water quality issues in NZ need to consider the full context of freshwater; its role in environmental processes, its natural chemical variability in that role and its use and value to New Zealanders. Those engaged in regional and national government initiatives, such as the Land and Water Forum, do (I believe) already have an appreciation for this context.”
Prof David Hamilton, Waikato University and President of the NZ Freshwater Sciences Society (NZFSS) comments:
“The report by the Parliamentary Commission for the Environment (PCE) provides a wideranging snapshot and history of water quality changes in New Zealand, suitable for educating and informing the public, water stakeholders, policy-makers and politicians.
“It indicates how water quality issues are by no means a recent phenomenon. Problems with bacterial contamination leading to human health issues and sediment erosion causing sedimentation problems and flooding of downstream waterbodies have been a persistent and widespread problem in New Zealand with the establishment of urban areas and removal of forest cover for pasture.
“The report highlights the historical legacy left by land use change, which unitary environmental management authorities continue to deal with today. However, diffuse nutrient pollution from agricultural sources has rapidly emerged to be one of the greatest environmental challenges. The report has identified the need for dual control of nitrogen and phosphorus to begin to address some of the present-day issues with diffuse pollution.
“The PCE report has pointed to the important role that scientists play in uncovering the cause-effect relationships that influence water quality. It has also effectively issued a challenge to scientists; to better communicate the outcomes of scientific studies into implications for managing water at a catchment scale.
“NZFSS has strongly advocated for a non-partisan, science-based approach to freshwater management but continues to be either absent or underrepresented from strongly stakeholder-dominated forums relating to water management. As the PCE report indicates, decision-making questions must be addressed in a context of sound scientific knowledge; the implication is that scientists, managers and policy-makers need to be more constructively engaged in this process, right through to policy level.”