Hydrology is the oldest application of science to human welfare. The earliest exercise of government arose from the need to manage water. If clean and sufficient water is to be ensured for the future new applications of science, more effective organizations and governmental actions are essential. Indeed, without a fundamental change of approach to the management of interactions between water and land, it could well be impossible to support the population projected for the next century.
The consequences for public health of shortfalls of water in the quantities, and of the quality, sufficient to meet basic human needs, have serious effects, in particular, on the vulnerable, the disadvantaged and the socially excluded.