How to have quality freshwater and plenty of it
Julia Talbot-Jones of Victoria University of Wellington argues against piecemeal measures to improve our rivers and waterways.
On Sunday, the water world came together to celebrate rivers and waterways under the auspices of World Rivers Day.
It seems timely that this year’s event fell in the week of global climate action. Water is the primary medium through which the world will feel the effects of climate change as water availability becomes less predictable in many places and increased incidences of flooding begin to affect water points and sanitation facilities and contaminate water sources.
In New Zealand, the risks of climate change are likely to exacerbate many of the issues the newly released National Policy Statement for Freshwater Management is seeking to address. In historically arid areas, such as the east coast of the South Island, precipitation is forecast to reduce, potentially exacerbating issues of allocation. In other areas, increased levels of precipitation could negatively impact water quality as increased runoff from rural and urban areas enters waterways.
Likewise, climate change is likely to affect freshwater biodiversity. Taonga, such as native fish, are likely to become further range-restricted because of increasing temperatures, while disruption of freshwater habitats and communities may induce local extinctions and shifts in species distribution in some freshwater systems.
Such linked issues are likely to be further amplified by the interrelationship between scarcity and quality. Limited water supply intensifies issues concerning water quality. For example, low water levels can lead to warmer stream temperatures. This can result in increased algal growth and induce shifts in macroinvertebrate communities, which are a common measure of stream health. Similarly, declining water quality can incentivise users to move away from traditional water sources, opening up previously untapped water sources to new pressures.
Unfortunately, by not simultaneously addressing issues of quality and allocation, the new National Policy Statement misses the opportunity to capture the full suite of benefits that could arise from implementing an integrated water governance framework across the country. It also undermines our ability to action the frequently espoused ‘holistic’ approach to delivering desirable health and wellbeing outcomes for New Zealand’s waterways and communities embedded in Te Mana o te Wai.
Taking a piecemeal approach to water quality and quantity issues risks placing regulatory emphasis on issues that may not deliver the greatest net benefits for all New Zealanders. For instance, directing resources towards cleaning up rivers and streams that are under increasing allocation pressures is only likely to achieve a second-best return for communities and biodiversity.
International water governance models that take an integrated approach to management consistently deliver greater net benefits to users and managers alike. Subsequently, a better approach for New Zealand would be to map a timeline for addressing allocation issues and to outline how quantity measures are expected to complement the newly proposed quality standards.
Although addressing scarcity will not be easy in the New Zealand context, approaching it in a dynamic and integrated way will help ensure the benefits of transforming our freshwater governance framework can be felt by communities and its biodiversity. It is only through emphasising the joint benefits of clean and abundant supply that we can hope to have reason to celebrate future World Rivers Days in the face of a changing climate.