Drought plans are very important since they create a framework for a risk management approach. These plans are developed to "provide tools to inform decision making, define tasks and responsibilities for all drought management, and identify a host of mitigation and response actions" (Stefano et al. 2015). Because each drought event can evolve in unpredictable ways and affect different areas, some ad hoc mechanisms must be arranged by governmental agencies and sectoral institutions to respond to evolving drought conditions. In the following section, a description of the developmental frame of drought management in Spain and Portugal, based on DMPs' implementation, is presented. Both Portuguese and Spanish DMPs provide a framework for action in drought situations, showing some common tools to trigger actions (drought indicators), measures associated with each drought situation, and the main entities and roles in drought management.
The National Hydrological Plan Act established in 2001 stated that DMPs should be developed by the RBDAs. Following the severe drought episode affecting the IP in 2005, Spain developed a guidance document for DMPs. As a consequence, DMPs were developed for all Spanish RBDs and approved in 2007 by ministerial order, being considered as specific plans of RBMPs, according to the Hydrological Planning Royal Decree (rD 907/2007). The National Hydrological Plan also stated that public administrations responsible for urban water supply systems with more than 20,000 inhabitants should have a contingency plan for drought situations (BOE 2001).
Spain was a pioneer in the development of hydrological drought plans at the basin scale, which are based on accurate real-time monitoring information on the hydrological conditions of the basin. The hydrological drought plans are developed at the basin level by the different water management agencies (e.g., the Ebro basin drought plan can be obtained at http://www. chebro.es/contenido.streamFichero.do?idBinario=5889). These drought plans are independent for each basin since they are adapted to the specific basin characteristics, but all use the same concept for drought monitoring (detailed below).
Spanish DMPs include a drought diagnosis (i.e., drought indicators and thresholds), a program of related measures (of different types, associated with each drought status), and a management and follow-up system (with an organizational framework to deal with drought in each river basin district) (CHG 2007; Maia 2009). The 2007 DMPs are currently being revised and adapted to the second cycle RBMPs (adopted at the beginning of 2016) and are expected to be completed by the end of 2017 (BOE 2016).
Spain does not currently have an active drought early warning system (DEWS); however, the drought indicators to be defined in the revised DMP are expected to include seasonal meteorological forecasts, provided by AEMET, the Spanish national meteorological entity. Currently, the contingency plans are only developed in some large cities, such as Madrid, Barcelona, Seville, and Malaga (MAPAMA 2016a).
No DMPs have been developed to date at the RBD scale. A proposal for a national Plan for Prevention, Monitoring and Contingency for Drought Situations (hereafter referred to as PT DMP) was made public in 2015, but it has not yet been officially approved (APA 2016). As illustrated by the severe drought of 2004/2005, drought situations have been managed in a reactive way, mostly based on the activity of a drought commission established by the government in cases of severe drought, operating at the national level. During the next severe drought period, in 2012, the Commission (CSAC, as referred to above) was established as a permanent body together with a technical advisor working group (DR 2012). The PT DMP proposal (developed by the working group) considers the establishment of drought indicators and drought levels and sets some specific measures that are associated with those levels. However, at the moment, those features may not be fully implemented because of the DMP's provisional character. A pilot version of a DEWS was developed by the former Portuguese Water Authority (INAG) and was presented to the public in 2011, but it has not yet been implemented (Maia 2011).
The DMP proposal provides information about drought prevention, monitoring, and contingencies. This plan includes (1) some preventive structural and nonstructural measures, (2) the variables to be used for drought indicator development, (3) the periodicity of drought monitoring, and (4) a proposal for action during a drought event (such as the entities involved and the measures associated with each drought alert). The DMP proposal also describes the terms of public disclosure, including the frequency of publication of monitoring results by the entities involved. Furthermore, the proposal calls for all public water supply and irrigation supply management entities to prepare a contingency plan for drought situations.