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... In addition, the Júcar Basin Agency (JBA) has developed indices that allow determining the appropriate measure to deal with a drought event. These indices called Operative Drought Monitoring Indicators (SODMI), use real-time information provided by the Automatic Data Acquisition System of the DHJ (Estrela, 2006), the data contain information about precipitation and state of reservoirs, aquifers and rivers. ...
Droughts cause significant socio-economic and environmental impacts, so it has become an extremely important element in decision-making within water resource systems. For this reason, the research in this field has increased considerably over the last few decades. In order to be capable of making early decisions and reducing drought impacts, it is necessary to predict the occurrence of such events months or even years in advance. In this sense, various methods have been used to predict the occurrence of droughts. At present, seasonal forecast data can be used to forecast meteorological, hydrological, agricultural and operational droughts. However, the seasonal forecast data of these dynamical ocean-atmosphere coupled models must be analyzed in an exhaustive way, since it is known that these models may not adequately represent the climatic variability at river basin scale. Hence, this paper presents a new methodology for assessing the skill of a climate forecasting system in order to predict the occurrence of droughts by using contingency tables. The indices obtained from the contingency tables are necessary to perform the analysis of the predictive ability of the model in a semi-distributed way. All this taking into account the intensity of droughts using different scenarios based on the threshold below which it is considered to be in drought. Finally, a single value is obtained to determine the predictive ability of the forecasting model for the entire basin. The proposed methodology is applied to the Júcar river basin in Spain. It has been found that the analyzed forecast model shows better results than those obtained using an autoregressive model. Further work is needed to enhance climate forecasting from the perspective of water resources management, however, it should be mentioned that this type of data could be used for drought forecasting, allowing possible mitigation measures.
... Otras definiciones de sequía la relacionan con las consecuencias que tiene para las actividades humanas. Una definición de sequía, que incluye una mención al impacto social, es por ejemplo: "Disminución temporal y significativa de los recursos hídricos que afecta un área extensa con consecuencias socioeconómicas adversas durante un periodo suficientemente prolongado" (Estrela-Monreal, 2006). Las definiciones que utilizan los monitores de sequía de América del Norte (DOF, 2012) para los diferentes niveles de intensidad también ponen la atención en los efectos de la sequía. ...
The purpose of this article is to present and review the main strategy choices for Mexican cities against drought. The main ideas are: 1) that drought has not a direct effect on urban water systems but it is mediated by water infrastructure and by management; 2) that drought impact mitigation should be carried out mainly through adaptive water demand management; and 3) that the main obstacle for cities to carry out adaptive water management is the lack of reliable information systems. The article reviews the exposure of Mexico's urban municipalities to drought, presents a model for the analysis of drought impact where water management is the critical element and points out that the main obstacle for water utilities tackle and mitigate drought is the lack of an information and indicator system to monitor water waste, meter consumption and effective revenue collection. The establishment of information management and the improvement of these opportunity areas constitute the critical step forward for utilities undertake more effectively and sustainably actions against the recurrent droughts. This kind of management is what we call adaptive water management.
... During the last large drought episode suffered in the basin, CHJ developed a Standardized Operative Drought Monitoring Indicators system (SODMI) [17]. In essence, the SODMI uses real-time information provided by the Automatic Data Acquisition System of CHJ on the state of reservoirs, aquifers, rivers, and precipitation to produce standardized indexes for some selected elements in the basin. ...
Drought is a major concern for water managers in many regulated river basins throughout the world. Especially at those in which the equilibrium between resources availability and water uses is very fragile, making that deviation below normality compromises the capacity of the system to cope with all the demands and environmental requirements. Since droughts are not isolated events but instead they develop over time in what could be considered a creeping behavior, it is very difficult to determine when an episode starts and how long will it last. This lack of knowledge difficults both long term and short term decision-making processes. The Jucar River and the Turia River basins are in the Mediterranean region of Spain. The resources of the two rivers are used jointly to meet the different water uses within the region, especially urban demands and environmental requirements with particular attention to the good status of the Albufera Lake. The climate change effects in this area are predicted to be particularly severe in this area [1]. However, recent studies [2] showed the great variability in drought patterns advising of the great caution to be exercised when such events are managed. This paper presents a methodology to assess the best behavior achievable for a water resources system, and we apply it to the joint system of the Jucar River and Turia River basins. We create an optimization model of both basins with the decision support system AQUATOOL [3] and feed it with multiple stochastic streamflow series in a Monte-Carlo process, similar to what is proposed in [4] and [5]. The results are particularly suitable for system planning and evaluating the best performance of the system under the effects of climate change.
... These exceptional measures may also include: 2005, 2006 and 2009, while in 2007 and 2008 they only covered the upper sub-systems of the El Vicario, Gasset and Peñarroya, which suffer from a water scarcity problem (i.e. demand is structurally higher than average supply) rather than from what is commonly (and wrongly) called 'persistent drought'. Even within a preventive risk management approach, as defined under the Spanish drought planning framework, it is quite difficult to avoid such emergency responses, and drought decrees are likely to continue as a cornerstone of drought policy in the near future (Estrela, 2006). For the Guadiana, the set of exceptional measures approved between 2004 and 2006 amounted to almost 55 million Euros, as shown inTable 3. ...
Droughts are recurrent climatic hazards that cause major environmental, economic and social impacts, and
increase the conflict potential between countries sharing transboundary river basins. The shared river basins
of the Iberian Peninsula, and the Guadiana in particular, are of major significance for Mediterranean Europe,
as examples of basins marked by aridity, water scarcity, and drought risk. A political agreement (the Albufeira
Convention) regulates water issues between Portugal and Spain but an exception regime is applied under
drought conditions, and the Convention looses its effectiveness. The two countries have different planning
and management policies to tackle droughts, based on distinctive administrative and socio-economic structures.
This paper analyses each country’s framework, and assesses the level of cooperation and compliance with the
basic pillars of transboundary water governance, identifying the potential and constraints for shared and effective
transboundary drought planning and management. The analysis conducted shows how both countries fail to
identify common benefits and goals, based on a shared process of public participation (which still does not
exist). The paper concludes that, before aiming for a shared or joint planning process, both countries need
to incorporate adaptive and precautionary management procedures into their planning systems and cooperation
structures.
... Figure 4has been obtained using data coming from National Indicator System of the Ministry web page (http://www.marm.es). The evolution of the indicator representative of drought status at Júcar river basin is shown in Fig. 5Estrela 2006). DMPs have proved to be useful and efficient tools to manage water resources under drought episodes. ...
Water is a strategic resource for the economic, social and environmental development. However, water scarcity and droughts are current challenges to this growth, as it is reflected in European Union (EU) water policies, and in national and regional growing initiatives. In addition, these water related issues could worsen by climate change effects, adding pressure to already water stressed areas. This paper presents a general overview of drought management in the European Union, reviews scientific and technical advances, the status of implementation of policy tools and focuses on drought management plans. It analyses the specific case of Spain, a country characterised by presenting a high irregularity in temporal and spatial distribution of water resources and numerous areas affected by water scarcity and droughts. Details are presented on the National Drought Indicator System and drought management plans approved in 2007 in Spain, which represent strategic tools with positive results in drought warning and impact mitigation respectively.
... Recession curves allow evaluation of this feature. In other words, the vulnerability of aquifers to drought is related to how quickly they discharge stored water, which in turn depends on recession coefficients (Estrela, 2006). An adequate summer water supply is of great importance to Spain where the main source of national income is tourism; most of the country's annual 60 million visitors come at this time when the drought is at its worst and urban demand for water at its highest. ...
This paper proposes a method for assessing the renewable groundwater reserves of large regions for an average year, based on the integration of the recession curves for their basins' springs or the natural baseflow of their rivers. In this method, the hydrodynamic volumes (or renewable reserves), were estimated from the baseflow. It was assumed that the flow was the same as the natural recharge, and the recession coefficients were derived from the hydrogeological parameters and geometric characteristics of the aquifers and adjusted to fit the recession curves at gauging stations. The method was applied to all the aquifers of Spain, which have a total renewable groundwater reserve of 86 118 hm—four times the mean annual recharge. However, the spatial distribution of these reserves is highly variable; 18.6% of the country's aquifers contain 94.7% of the entire reserve.Citation Sanz, E. & Recio, B. (2010) A method to assess annual average renewable groundwater reserves for large regions in Spain. Hydrol. Sci. J.56(1), 99–107.
... For example, in Spain there is a clear sharing of responsibilities among the involved bodies, as well as a clear definition of the contents of a potential drought mitigation plan since the beginning of the century. Law 10/2001 applies a proactive approach to contend with drought risk by defining the basis for developing a system of hydrologic indicators to monitor and forecast drought events; giving responsibility to basin authorities to prepare drought plans and to municipal water agencies to prepare drought emergency plans; and assigning responsibilities for drought declaration (Estrela 2006). ...
The Mediterranean region has an extensive hydraulic infrastructure and complex socioeconomic interactions among water users. In this region, competition for water among urban, agricultural, industrial, and environmental demands is strongest in times of water scarcity. Allocation of scarce water in the face of multiple demands is a challenging task that requires careful analysis. Precipitation decreases may likely be translated into drought periods in most cases. Nevertheless water scarcity (the shortage of water resources to serve water demands) not only depends on drought or precipitation deficits but also on water management. Adaptation options depend on the strategic contingency planning and management decisions that affect water resources systems. The risk management of water scarcity and drought depends on the level of water scarcity. Therefore, an adequate diagnosis of the water scarcity level is essential to anticipate the possible solutions. This study proposes a methodology for drought risk management based on the evaluation of 4 indicators of water scarcity to be used to define the thresholds of risk management actions. Based on the definition of thresholds, the study proposes the implementation of risk management actions that may be used for responding to each water scarcity situation.
... For instance, in Spain, the Law of the National Hydrologic Plan, approved in 2001, established new legal instruments for drought management. The action is based on three main instruments (Estrela, 2006): (i) a drought monitoring system based on drought indicators for each Basin Authority and for the entire country; (ii) special Drought Management Plans for Basin Authorities; and (iii) emergency Drought Plans for urban water supply systems serving more than 20,000 inhabitants. ...
This paper provides an overview of the challenges presented to the managers of water supply systems by drought and water scarcity. Risk assessment is an essential tool for the diagnostic of water scarcity in this type of systems. The evaluation of the risk of water shortage is performed with the use of complex mathematical models. Different alternatives to address the problem are presented, covering a range of methodological approaches. The actions adopted to prevent or mitigate the effects of water scarcity should be properly organized in drought management plan. The process of development and implementation of drought management plans is briefly described presenting several examples taken from the Mediterranean region.
