Compensation and risk management mechanism in water allocation

• Autor(a) principal: Samiria Maria Oliveira da Silva
• Data de Publicação: 2015
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFC
• Texto Completo: http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=14819
• topic: AlocaÃÃo de recursos - Ãguas; Risco; CompensaÃÃo; Water allocation; Risk; Compensation; ENGENHARIA CIVIL

The process of water allocation between different and competing uses in an uncertain climate scenario reinforces the motivation to study risk management of water systems. In this way, the purpose of this study is to propose the incorporation of a climate risk management mechanism in the process of water allocation, aiming an equitable and efficient management of these resources. For this, an aggregate model consisting of a reservoir of regulation and two users (urban supply and irrigation) was used to build and evaluate a financial mechanism. Afterwards, a disaggregation model consisting of multiple reservoirs was used to apply the concepts defined in the previous model. Initially, an indicator was chosen to be used as a trigger for the financial mechanism. This trigger started the mechanism whenever any rigorous state of drought in the water system was detected, which were classified in four different types: moderate drought, severe drought, extreme drought and exceptional drought. The amount of compensation was calculated based on the benefits achieved by the sector that lost water guarantee during the scarcity period. This evaluation was performed by the application of two methods for apportioning the water availability: linear apportionment and priority system. The available water flow for allocation was calculated using the reservoir operation strategy with inflows zero in the semester of the year. However, the incorporation of climate information in the process was also tested. Two triggers were proposed for the financial mechanism: Drought indices and Rationing level. The drought indices were built based on the average precipitation (standardized precipitation index), the inflow (standardized index flow) and the final volume of system operation (synthetic index). The rationing level mechanism is based on the available water flow for allocation and it was chosen due to its existing relation with the volume stored. This relationship allows the trigger to perform well both for the drought detection probability as for the false alarm. In addition, a conceptual framework for incorporating the financial mechanism to charge for the water use was elaborated, as well as an evaluation of the performance of the system as for the incorporation of the financial mechanism through two indicators: economic efficiency and equity (allocative justice). The performance evaluation showed that the payment of compensation in a period of drought due higher warranty (priority) of other uses operates to a greater equity and efficiency in water allocation. In order to keep the funds collected by the charge to cover the compensation, a regularization fund that has annual revenues of parcels carried out by the urban water supply and by the government was created. This regularization fund ensures the financial sustainability and also a good ability to adapt the incorporation mechanism to the collect instrument. Consequently, the financial compensation is a viable option for both water managers, who will have greater flexibility in their decisions, as well as for the water resources system, that will have more equity in their process of water allocation.