ABSTRACT
Drought represents a potentially disastrous threat to water supplies, agriculture, and environment. The severity of its impacts makes the traditional emergency approach inadequate and calls for a risk management approach, particularly in order to reduce water shortages in water supply systems. In this chapter the role of legal and institutional frameworks is discussed, with particular reference to the actions aimed at reducing vulnerability to drought, as natural hazard, suggested by the International Strategy for Disaster Reduction (ISDR) and by the European Union. Contents of drought-planning instruments (at strategic, tactical, and emergency levels) to define preparedness and mitigation measures are discussed. The methods for the assessment of water shortage due to drought in water supply systems are described with reference to the strategic planning and to the operation of systems. The review focuses on: (1) the drought indices to be used for an effective monitoring and early warning system, (2) the methods to assess the risk of water shortage due to drought, and (3) the measures for reducing societal vulnerability to drought and mitigating its impacts. Better coordination among the drought-preparedness planning tasks and the adaptive operation of water supply systems to prevent severe shortages also through a more extensive use of early drought warning are suggested. Further research needs are identified.
