Advanced computer models are commonly used to simulate reservoir system's performance. If the number of possible management scenarios is large, it can be extremely difficult to follow related system's operation and get a valuable picture on its spatial and temporal behavior. The decision maker or analyst can be overburdened by quantity and complexity of information generated by model, particularly if system operation is repeatedly simulated for multiyear periods. Related problem is how to select the scenario with most desired long-term consequences. Possible approach is to use selected parts of model's output and re-interpret system behavior by means of certain performance indicators, create appropriate decision matrix and perform multi-criteria analysis to rank decision alternatives (scenarios). The paper proposes a methodology that includes:(1) multiyear simulations of system operation; (2) computing spatially and temporally distributed system performance indices such as supply reliability, resiliency and vulnerability; (3) unbiased entropy-based weighting the importance of performance indices; and (4) final ranking of scenarios by means of multi-criteria analysis. The number of scenarios and number of performance indices is not restricted, and to account for possibly large sets of scenarios, an ideal-point-distance multicriteria method TOPSIS is suggested. Proposed methodology appeared to be confident and robust in proof-of-concept application in Brazil.

There are two mainstreams when using the analytic hierarchy process (AHP). One is the standard applications of crisp distributive and ideal mode versions. The other is characterised by fuzzification of the AHP methodology and by attempts to better tackle inherently uncertain and imprecise decision processes with quantitative and qualitative data. The latter is characterised by different approaches to fuzzificating the decision problem; the way of conducting judgment and evaluating process; and finally, in synthesising the results and manipulating fuzzy numbers to devise priorities for the decision alternatives. This paper presents a fuzzy methodology for solving fully structured decision problems with criteria, subcriteria and alternatives. It follows the logic of AHP in a simple and straightforward manner, efficiently aggregates criteria and sub-criteria into unique hierarchical level and applies a total integral method for comparing decision alternatives. The proposed methodology has been used for the assessment of water management plans in part of the Paraguacu River Basin in Brazil.

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Este artigo tem o objetivo de avaliar a viabilidade de implantação do reúso agrícola de água como elemento mitigador dos efeitos da seca no semiárido baiano, analisando as razões para a implementação de políticas de reúso de água sob o ponto de vista de agricultores e de formuladores de política de recursos hídricos. A pesquisa foi localizada em São Domingos, município da região semiárida da Bahia e a metodologia consistiu na realização de entrevistas semiestruturadas e aplicação de questionários fechados. Os resultados indicam que a questão cultural se constitui em obstáculo importante, seja pelo sentimento de repulsa, ou pela crença de que a prática pode trazer riscos à saúde, entretanto, os principais fatores que dificultam a implantação de reúso são de ordem econômica, destacando-se o pouco valor da produção agrícola na referida região.

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There is a growing interest in the literature on the theme of the water–energy–food nexus, as there is growing recognition that sectors that share natural resources have interdependent and interconnected systems. Despite the widespread popularity of nexus thinking, it still lacks standardized procedures and methodologies to assist in its development. Therefore, this paper proposes, from a literature review, a systematic procedure to assist in the development of management models based on nexus thinking. To this end, 304 papers were analyzed using the following criteria: nexus concept, type of approach, geographic scale, elements in the nexus system, application context, and types of assessment methods and tools. The results of the review served as the basis for determining the procedure, which consisted of four steps: (a) understanding nexus thinking, (b) identification of composing variables, (c) evaluation (diagnosis and prognosis), and (d) decision-making. In addition to the standardization of these steps, the main information used to compose the procedure was organized and synthesized with a mind map.

Este artigo define critérios objetivando avaliar graus de implementação da Política Nacional de Recursos Hídricos (PNRH) em duas escalas de planejamento: uma bacia de rio de domínio da União (nível macro) e uma sub-bacia de rio de domínio estadual (nível micro). Sete critérios são propostos: cinco instrumentos de gestão (Lei no 9433/97) – outorga; cobrança; sistemas de informações, planos de recursos hídricos e enquadramento e duas condições de participação pública e gestão de conflitos – existência e atuação dos comitês de bacia e incidência de conflitos pelo uso da água. Cinco categorias de graus de implementação foram definidas: Muito Alto, Alto, Médio, Baixo e Muito Baixo. A metodologia foi aplicada à Bacia Hidrográfica do rio São Francisco e à sua sub-bacia do rio Salitre (BA). A análise mostra diferentes graus de implementação da PNRH em função da escala de planejamento (União ou Estado) e do critério analisado, apontando a necessidade de ações de gestão para apoiar a tomada de decisão em distintas escalas de planejamento.

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