Non-renewable groundwater resources: a ... - unesdoc - Unesco

CHAPTER 2 ■ SOCIAL AND ECONOMIC DIMENSIONS OF NON-RENEWABLE RESOURCES● The dependence of any aquatic ecosystems on the groundwater system, and whether thesecan be sustained (albeit in reduced form) through provision of compensation flow by localirrigation and/or aquifer recharge. This consideration will need to be realistically factoredinto the evaluation of the acceptability of the proposed groundwater development.In developing the groundwater mining plan, the socio-economic analysis will require planners tolook at other sectors besides water. Hence, modeling will be needed to guide the allocation ofgroundwater abstraction between sectors and over time, so as to determine the optimalabstraction schedule to maximise some economic criteria (often economic efficiency). However,the long-term socio-economic impacts may often be difficult to forecast accurately. But what isknown is that the non-renewable groundwater used today will not be available for future use,although it is often the case that the socio-economic benefits to future generations are oftengreater if some of that resource is used today rather than saved for future use.In summary the key principles that should adopted for the development of non-renewablegroundwater resources (Louvet and Margat, 1999) are :● the evaluation phase should result in estimates of the volume of groundwater that can beproduced in a fixed time-horizon with reference to an acceptable groundwater level decline● the development of non-renewable resources must be justified by socio-economic circumstancesin the absence of other water resources, and that its implementation is planned andcontrolled.Rationalisation scenarioIn the unplanned situation the socially-sustainable criterion implies that ‘rationalisation’ ofgroundwater extraction and use be imposed with the goal of achieving orderly utilisationof aquifer reserves (Figure 5), which will minimise quality deterioration, maximise groundwaterFigure 5Targets for groundwater resource management 'rationalisation scenarios'Concept of rationalizing previously indiscriminate, excessive, and poorly understood, exploitation through a combinationof 'demand-side intervention' and 'supply-side enhancement' measures with a clearly-defined long-termmanagement target which will allow systematic water resource and socio-economic planning.27