This chapter attempts to bring together a set of disparate concepts that are fundamental to examining water as a resource and establishing the seriousness of the current and future water scarcity. As is well known, there is a plentiful supply of water considered at a global scale. However, as we examine scales much closer to individual humans, a pattern of great heterogeneity emerges. Some parts of the world have plentiful supplies of water, others have severe droughts; some plenty of high quality water, others with badly polluted waters; in some the rivers flow full, in others they are devoid of water for many days of the year. It would be simple if these differences were due only to the physical climate, but careful examination shows that there are large differences within the same climate zones that cannot be explained purely by climate and topography. In these cases, one sees the hands of human interference in terms of governance, property rights, and sheer population size. The situation may become much more serious in the badly impacted areas as the great climate change experiment unfolds. There is huge uncertainly associated with the predictions of climate for the 21st century. The chapter is able to be optimistic in the face of such uncertainty by pointing to several technical, economic, and social developments that can reduce the human footprint on the scarce supplies of easily accessible water. By relying more on rainfed agriculture and agricultural trade to meet food needs scarce irrigation water can focus upon higher value and less water using crops or can be diverted to high value municipal and industrial uses; improving the efficiency of current irrigation technologies will free up large quantities of water for other uses; relying upon new ecological sanitation techniques can greatly reduce the impact on water quality; and low cost breakthroughs of desalination cost which are now economically competitive with alternative sources of fresh water to meet the needs of urban populations anywhere in the world. In order for these solutions to the emerging crisis to be adopted much more attention will have to be paid as to how we as individuals and communities approach and the world community approaches the governance of water. A successful shift to effective governance will enable us to have sustainable water supplies for all well through the 21st century.
|Title of host publication||Water: Security, Economics and Governance|
|Editors||R. Quentin Grafton, Jamie Pittock, Maree Tait & Chris White|
|Place of Publication||Prahan Victoria, Australia|
|Publisher||Tilde Publishing and Distribution|
|Publication status||Published - 2013|