The need for research in water allocation
In January this year the Government identified four linked issues to be addressed in their “Programme of Action” for the sustainable development of New Zealand: water quality and allocation, energy, sustainable cities, and child and youth development. The science community is well prepared to tackle water quality and allocation, and this issue of Water Resources Update provides some pointers.
In comparison with many other countries, New Zealand is remarkably free of disputes over water. Most of the bigger cases before the Environment Court in the last three decades have related to the hydro industry. However, there is likely to be more conflict in future between conservation for in-stream values versus water-takes for agricultural development. The proposed water conservation order on the Rangitata River is an illustration of that.
There are two major issues on the eastern side of New Zealand from Hawke’s Bay to Otago: climate predictions are for less rainfall in the next 50 years, and the demand for water for irrigation is increasing rapidly (irrigated land doubles every 10 years). We are faced with the following resource scenarios: less water in east coast foothills streams; lower groundwater tables and less water in spring-fed streams; disappearance of lowland ephemeral streams; proliferation of small farm dams, and significant takes from the major east coast rivers.
How much water is there? Where is it? What is the groundwater resource? What are the sources of the water we use, and how are they affected by climate? What natural in-stream values are affected by decreasing flows or greater flow variability? How can we use the water more efficiently? The National Centre for Water Resources has an important role in helping answer these questions to allow the Government to meet its goal of “adequate, clean freshwater available for all”.
Clive Howard-Williams, General Manager, Freshwater, NIWA