System Evaluation of Billings and Guarapiranga Reservoirs

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1 System Evaluation of Billings and Guarapiranga Reservoirs Marlei Roling Scariot Abstract In most studies of water resources it is essential consider, in addition to the physical environment, the socioeconomic conditions of the Region, since changes of the basin catchments landscape cause rapid changes in the bodies of water. Economic development has always been dependent of water resources and the water works as a feature for development, because it is used for many purposes directly related to the economy. In addition to the economic uses of a water body, it can also suffer the impact of multiple sources of pollution in the watershed, as industrial effluents and municipal sewage pollution, in agricultural areas such as fertilizers and pesticides from agriculture and effluent discharge from animal farms. The management of these interests of different segments of society is still a challenge for many countries. The problems related to water resources are quite singular in different regions of the country, however, certain conflicts for the use of water resources, are already a common feature in many Brazilian regions. This study aims to evaluate the use of water from the Billings Reservoir by the São Paulo Metropolitan Region. Billings reservoir was originally designed to produce electricity, but at the present is used as the largest water reservoir of metropolitan Sao Paulo region, though its water may not be fully exploited, due to the high degree of pollution and quality degradation, which was contaminated for decades by the polluted waters of the Pinheiros and Tiete rivers. Guarapiranga reservoir is responsible for supplying about four million people living in the Southwest region of the capital of São Paulo State. These reservoirs are strongly influenced by urban sprawl urbanization, industrial growth and especially the disengagement of the state in improving the water quality of rivers that feed the reservoirs. Effective management promoted by the National Policy of Water Resources by means of installation of Watershed Committees, promotes the water use charging. Through the results of the emergy evaluation, it is expected to guide public policies for sustainable use of the water resources. Introduction The main Brazilian problems related to water supplying come from the combination of exaggerated growth of local demands and the water quality degradation. This scenario is a consequence of the unplanned growth of urbanization and industrialization processes. One of the first Brazilian experiences in water resources management was the creation of the water code in 1934, which was a bureaucratic model to regulate the multiple uses of water resources. Since this beginning point the management suffers significant changes and the model adopted currently is an integrated participative systemic model. LIBRO DE DOCUMENTOS COMPLETOS CD ROM ISBN

2 Regional distribution of the water resources in Brazil is of 70% to the North region, 15% to the central west, 12% to the south and south east and 3% to the north east region (Borsoi, 1997). São Paulo State is located in the south east Brazilian region, which presents the biggest water consumption. The Water Resources Agency of São Paulo State has an advanced process of water resources management with 20 watershed management committees. Groups from the different social sectors compose these committees. It is a relatively new kind of organization in Brazil and is responsible to developing the watershed management plan. These committees have document information with the compilation of water resources relevant information however most of them do not contain strategies, plans, action steps or future scenarios. In order to support the watershed committees to improve basin planning this study propose to apply emergy evaluation and system dynamic models to understand watershed conditions and to evaluate the main aspects of human impact to the water quality of Billings and Guarapiranga reservoirs. The present study proposes to makes use of multidisciplinary methods of analysis as the Geographic Information System to characterize the study area and to use the energy system language to create a system diagram, modelling and emergy evaluation. Study Area Large urban areas near natural systems are a challenge for water research management and this kind of study area was selected for this work. At the Metropolitan Region of São Paulo stands out the Billings and Guarapiranga Reservoirs. Billings Reservoir was originally designed to produce electricity, but at the present it is used as the largest water reservoir of metropolitan Sao Paulo region, though its water may not be fully exploited, due to the high degree of pollution and quality degradation, which was contaminated for decades by the polluted waters of the Pinheiros and Tiete Rivers. Guarapiranga reservoir is responsible for supplying about four million people living in the Southwest region of the capital of São Paulo State. These reservoirs are strongly influenced by urban sprawl urbanization, industrial growth and especially the disengagement of the state in improving the water quality of rivers that feed the reservoirs. Methodology Geographic Information System Mapping the main variables of the system permit to view some territorial relationships, some spatial arrangements, making possible to preview some implications because it create different spatial conditions to support a correct system analyze. The software MapInfo is used to create thematic maps and LIBRO DE DOCUMENTOS COMPLETOS CD ROM ISBN

3 help in the area characterization. Map 1 shows the percentage of municipal domestic sewage treatment of the Upper Tietê Watershed and location of Billings and Guarapiranga Reservoirs. Figure 1. Upper Tietê watershed sewage treatment (%). From this map it is clear that most of the metropolitan region (19 cities) of São Paulo can treat just less than 30% of the urban sewage. São Paulo city treats around 80% of the sewage, but considering the huge urban concentration of this city (around 11 million of people; IBGE, 2007) the untreated percentage helps to completely degrade the rivers in this region. The main rivers that receive directly or indirectly all this sewage and also industrial effluents are Tietê and Pinheiros Rivers. In order to produce electric energy in the Henry Border Hydroelectric Power Plant, Pinheiros and Tietê Rivers had its flow reversed to feed Billings Reservoir during decades. This process becomes a source of pollution for the reservoirs raising the pollution levels higher than 100% the allowed by the São Paulo State legislation. The reversion processes is presently forbidden by government but most of the reservoir s water remain inadequate for human been uses. The resuspension of contaminated sediment is an important source of pollution of the water column. Figure below shows a system diagram representation of the reservoirs. Since water is contaminated the fishery (Maruyama, 2007 and Rocha, 1985) is artisanal and restricted to few places and the main use is to electric energy production and for water treatment plants. LIBRO DE DOCUMENTOS COMPLETOS CD ROM ISBN

4 System Diagrams The system energy diagram was developed for a reservoir using Odum s energy language (1983). Figure 2 pictures the diagram with the multiple inputs, outputs, internal processes and interactions that contribute to understand the main variables that represent the system. Figure 2. Energy Diagram of Billings Reservoir. Energy system modelling and Emergy evaluation (Odum, 1987; Odum, 1988; Ulgiati et al., 1994; Odum, 1996; Brown, 1997, 1998, 2001; Odum, 1998; Lagerberg, 1999) are presented as a research proposal to study. Effective management promoted by the National Policy of Water Resources by means of Watershed Committees installation and promoting the water use charging. Through the results of modelling, it is expected to guide public policies for sustainable use of the water resources. Emergy evaluation is a decision support tool for evaluating strategies on national as well as regional plans, and can provide a real value (Emdolar) for water resources which will be compared with the watershed present cost of the water. Acknowledgements: The work described in this paper was supported by the Federal University of São Paulo State/Diadema and ALFA/SUPPORT project. LIBRO DE DOCUMENTOS COMPLETOS CD ROM ISBN

5 References Borsoi, M.F.B.; Torres, S.D.A. A política de recursos hídricos no Brasil. Revista do Banco Nacional de Desenvolvimento Econômico e Social (BNDES). Rev p Brown, M.T. and Ulgiati, S Emergy-based indices and ratios to evaluate sustainability: monitoring economies and technology toward environmentally sound innovation. Ecological Engineering 9 (1997), pp IBGE, Brazilian Institute of Geography and Statistics. Available at: accessed: 13/11/2009. Maruyama, Lídia Sumile. A pesca artesanal no Médio e Baixo Tietê (São Paulo, Brasil): aspectos estruturais, sócio-econômicos e de produção pesqueira. Dissertação de mestrado. Programa de Pós-graduação em Aqüicultura e Pesca, Instituto de Pesca/APTA/SAA-SP. São Paulo, Odum, H.T. (1983) Systems Ecology: an introduction New York: Wiley Interscience,. 644pp. Odum, H.T.; Nils, P. (1996) Simulation and evaluation with energy systems blocks. Ecological Modelling. Vol. 63, pp Odum, H. T Environmental accounting. EMERGY and environmental decision making. Wiley & Sons, Inc., New York, Odum, H. T Emergy evaluation. In: Ulgiati, S. Brown, M. T. Giampietro, M. Herendeen, R. A. & Mayumi, K. (eds.). Advances in energy studies. Energy flows in ecology and economy. Musis Publisher, Rome, Italy, 1998, pp Rocha, Aristides Almeida ; Denise Navas Pereira; Helcias Bernardo de Pádua. Rev. Saúde Pública vol.19 no.5 São Paulo Oct Fishing yield and chemical contamination of the water of the Billings Reservoir, S. Paulo (Brazil). LIBRO DE DOCUMENTOS COMPLETOS CD ROM ISBN

6 Citar este artículo: Apellido y Nombre de los Autores Titulo Completo publicado en: Cuartas Jornadas de Economía Ecológica de ASAUEE : Asociación Argentino Uruguaya de Economía Ecológica / compilado por Horacio A. Feinstein y Walter A. Pengue. - 1a ed. - Buenos Aires : Asociación Argentino-Uruguaya de Economía Ecológica, CD-ROM. ISBN Economía Ecológica. I. Feinstein, Horacio A., comp. II. Pengue, Walter A., comp. CDD Fecha de catalogación: 29/10/2009 LIBRO DE DOCUMENTOS COMPLETOS CD ROM ISBN