State-of-the-art applications of short-term reservoir management integrate several advanced components, namely hydrological modelling and data assimilation techniques for predicting streamflow, optimization-based techniques for decision-making on the reservoir operation and the technical framework for integrating these components with data feeds from gauging networks, remote sensing data and meteorological weather predictions. In this paper, we present such a framework for the short-term management of reservoirs operated by the a drainage area of approximately 55,000 km and its operation for flood mitigation. Basis for the anticipatory short-term management of the reservoir over a forecast horizon of up to 15 days are streamflow predictions of the MGB hydrological model. The semi-distributed model is well suited to represent the watershed and shows a Nash-Sutcliffe model performance in the order of 0.83-0.90 for most streamflow gauges of the data-sparse basin. A lead time performance assessment of the deterministic and probabilistic ECMWF forecasts as model forcing indicate the superiority of the probabilistic model. The novel short-term optimization approach consists of the reduction of the ensemble forecasts into scenario trees as an input of a multi-stage stochastic optimization. We show that this approach has several advantages over commonly used deterministic methods which neglect forecast uncertainty in the short-term decision-making. First, the probabilistic forecasts have longer forecast horizons that allow an earlier and therefore better anticipation of critical flood events. Second, the stochastic optimization leads to more robust decisions than deterministic procedures which consider only a single future trajectory. Third, the stochastic optimization permits to introduce advanced chance constraints for refining the system operation.

Because of climate change, the frequency, intensity and/or duration of extreme weather events such as floods, droughts, storms and extreme temperatures is increasing. These events are often related to loss of property, money and life, especially in poor and developing countries where there is no or poor disaster management due to social and financial difficulties or due to a lack of synergy between the mitigation actions taken. Negative impacts can be reduced and losses can be better handled with proper water management techniques. However, these should not be handled solely with traditional management. The actual problem cannot be over simplified as merely a question of coping with resources availability and demand. Therefore, the present paper aims to summarize advances in weather forecasting and reservoir operation in the Upper São Francisco River, strategic to Brazil because it provides water to the semi-arid region and energy for economically thriving Brazilian regions. Moreover, it discusses challenges, opportunities and improvements needed to implement these advances in the current national integrated water resources management. This is mainly focused on water-related disaster mitigation.

A partir da compreensão da importância do papel do Estado nos serviços de abastecimento de água e esgotamento sanitário, este trabalho tem como objetivo apresentar uma proposta metodológica com critérios de priorização do investimento nessa área. Para tanto, a partir das atribuições previstas na legislação, o estudo classifica os municípios brasileiros a partir de um conjunto de indicadores, gerando um ranking por grupos de prioridades, de modo a equilibrar as condições de acesso aos recursos públicos. Considera-se que o aperfeiçoamento da alocação de recursos da União no setor, no momento de crise fiscal, deve seguir critérios que atendam cidadãos em situação de maior vulnerabilidade social e a municípios com os maiores deficit. Como resultado, são listados 961 municípios com graus de prioridade máxima e prioritários, bem como dois outros grupos com serviços precários de água ou de esgotamento sanitário que devem ser considerados, beneficiando 35,7 milhões de habitantes nesses grupos. Apontamos também sugestões adicionais no sentido de complementar as ações de investimento e de gestão integrada das políticas de saneamento e outras a este relacionadas.

The novel coronavirus pandemic has resulted in global socioeconomic impacts; however, there is still a need to improve understanding and data about its form and patterns of propagation. Therefore, studies on the role of water resources and sanitation should be prioritized, given the potential to serve as a means of dispersing the SARS-CoV-2 virus, which causes COVID-19 disease. So far, the RNA of the transmitting virus has been detected in domestic sewage in several countries, but there is, so far, no evidence of contamination by direct contact with these effluents. Even so, poor regions without adequate treatment of water and sewage, as occur in Brazil, must act in order to develop efficient policies to improve water quality aimed at public health. One of the options is the formation of a Hub that aggregates the various interrelated aspects of water and sanitation into a cohesive and actionable whole. It is essential to combine investment, research, and monitoring of water and effluent quality to improve sanitary security, water quality and human health, with an emphasis on the poorest sectors. The Hub would also serve as a means of controlling and monitoring the dispersion of pathogens such as the SARS-CoV-2 virus, thus mitigating economic and societal impacts.