[pt] O presente trabalho tem como objetivo estudar as formas de gestão participativa voltadas para o trato com recursos hídricos, efetivada através da atuação dos comitês de bacias hidrográficas, mais especificamente, Comitê IV do Rio Paraíba do Sul, atuante nas regiões hidrográficas dos Rios: Piabanha, Paquequer e Preto, objetivando entender qual é a percepção e o conhecimento dos membros e colaboradores atuantes, em relação ao seu papel, bem como sua importância como instância normativa e deliberativa no contexto dos recursos hídricos. Para realização do estudo optamos pela metodologia de pesquisa qualitativa, onde através da observação participante acompanhamos as reuniões ordinárias do referido comitê, e através de entrevistas semiestruturadas abrimos um canal de escuta com seus membros e colaboradores, com isto foi oportunizado identificar o que eles valorizam, e quais são as ações efetivadas para tomada de decisões que demonstrem a participação ativa da sociedade civil no processo. A resposta foi que identificamos que parte significativa dos membros, tem um olhar atento às condições ambientais locais e são sensíveis ao atual estado de conservação dos recursos hídricos, todavia nas questões conceituais e de efetiva normatização, na maioria dos casos, há registro de grandes equívocos, fator que prejudica o potencial de influência do grupo para formulação das políticas públicas na área temática, portanto, acreditamos que o resultado desse trabalho venha contribuir para mitigação dessa fragilidade destacada entre os membros do referido comitê. / [en] The political-institutional framework for water management was inaugurated in Brazil with the promulgation of Federal Law number 9.433 of 1997. The model defined by the legislation was the result of a complex debate between political agents, specialists and service users, and generally received very positive reactions celebrating the fact that Brazil was carrying out a reorganisation of the sector attuned to contemporary global trends - more horizontal, decentralised, participatory and effective. This model would allow for the environmental, economic, political, social and territorial dimensions of water use to be coordinated all at once. Hence, a river basin is defined as a territorial unit for implementing the water resources policy and a basin committee as a managing body for this territorial unit, with important responsibilities including conflict resolution, approval and monitoring of water resources plans, and setting up of systems for charging in the water use. The present work has as objective to study the forms of participative management aimed at dealing with water resources, carried out through the action of river basin committees, specifically the Piabanha Committee, with action on area of the river basin of the Rivers: Piabanha, Paquequer and Preto. Looking for to understand the perception and knowledge of the active members and collaborators in relation to their role, as well as their importance as a normative and deliberative instance in the context of water resources. In order to carry out the study we opted for qualitative research methodology, where through participant observation we followed the periodic meetings of said committee, and through semi-structured interviews we opened a listening channel with its members and collaborators, in this way it was possible to identify what they value most and what are the actions taken to make decisions.

[pt] A avaliação da recarga subterrânea e de sua variação temporal e espacial, em bacias hidrográficas, é essencial para estudos de sustentabilidade de recursos hídricos e requer, na maior parte das vezes, o uso de um modelo numérico de fluxo 3D. Geralmente, dados como mapas geológicos e pedológicos estão disponíveis, a localização e geometria das principais feições estruturais podem ser identificadas a partir de imagens de satélite, em ambiente SIG, e dados de hidrologia superficial e de elevação de terreno são fáceis de conseguir. No entanto, para se utilizar um modelo numérico que forneça uma primeira avaliação da sustentabilidade de uma explotação, é necessário alimentá-lo com dados de propriedades hidráulicas consistentes com a faixa de valores representativos dos tipos de rocha que compõe a bacia. Uma revisão de dados hidrogeológicos de uma série de localidades mostra que, enquanto as propriedades hidráulicas das rochas fraturadas apresentam uma grande variação em seus valores, quando analisadas de forma indiscriminada, ao serem agrupadas por tipo litológico, apresentam uma faixa de variação mais restrita (i.e. granito fraturado vs. gabro fraturado). Há um grande volume de dados relativos a projetos de disposição de lixo radioativo, mineração e engenharia civil, em diversos sítios ao redor do mundo, em que foram feitas investigações detalhadas do meio fraturado. Dados de um determinado maciço fraturado podem ser usados em outro, não investigado, como uma primeira aproximação, desde que possuam o mesmo tipo litológico e pertençam a ambientes tectônicos semelhantes. Este tratamento foi utilizado para modelar a vazão sustentável de uma pequena bacia de drenagem no Noroeste Fluminense. Dados relativos às estruturas dominantes e aos sistemas de fraturas foram extraídos de imagens de satélite, fotos aéreas e de afloramentos, e tratados em ambiente SIG. O modelo de fluxo subterrâneo foi construído com dados de elevação do terreno, mapas geológicos, registros hidrológicos históricos bem como mapas pedológicos e de uso da terra. O programa FEFLOW (Diersch, 1998) foi usado para simular a distribuição espacial e temporal da recarga subterrânea na bacia e diferentes cenários de explotação de água subterrânea. O modelo mostrouse capaz de fornecer uma primeira aproximação das reservas subterrâneas da bacia e de avaliar a relação entre o fluxo subterrâneo e dos cursos d’água superficiais, em condições naturais e nos cenários de explotação, sendo assim uma ferramenta útil para análises de sustentabilidade de exploração destes recursos. / [en] The estimation of groundwater recharge and its spatial and temporal variability in a drainage basin is essential for sustainability assessments and requires, in most cases, the use of an appropriate 3D numerical flow and transport model. For most drainage basins, the bedrock and overburden geology maps exist, the location and geometry of major structural features can be identified using available GIS databases, and surface water and terrain elevation data at an appropriate scale are readily available. In order to use 3D models to provide an initial assessment of the sustainability of the groundwater resource extraction of a specific drainage basin, the 3D model has to be populated with hydraulic properties that are consistent with the range of values that are representative of the rock types that underlie the drainage basin. A review of hydrogeological data from a number of sites shows that while there is a wide range in the hydraulic properties of fractured rocks in general, the range for individual rock types is more constrained, (i.e. fractured granite versus fractured gabbro). There is a great amount of hydrogeological data from fractured rock masses that have been investigated in detail as part of nuclear waste, mining and civil engineering projects around the world. Data from a specific site can be used as a first approach in another one, not investigated, once they have the same geologic characteristics and tectonic environment. This approach was used to model the sustainable groundwater yield of a small drainage basin in Southeast Brazil. Data on major structures and fracture systems were extracted from satellite images, aerial photos and outcrop expositions using GIS environment. The groundwater flow model was constructed using terrain elevation data, geology maps, hydrological records, as well as soil type and land use maps. FEFLOW (Diersch, 1988) was used to simulate the spatial and temporal distribution of groundwater recharge in the basin, using different pumping scenarios. The model was capable to yield a good estimation of groundwater resources in the watershed, as a first approach, and to assess groundwater and surface water relations in natural conditions and in stress scenarios being a useful tool for sustainability analysis of groundwater exploitation.

[pt] A dissertação intitulada a gestão do saneamento e o caminho da sustentabilidade: o caso da Bacia Hidrográfica Guapi-Macacu - RJ (BHGM) apresenta a necessidade de coordenação de ações na busca do atendimento dos Objetivos de Desenvolvimento Sustentável (ODS), principalmente o ODS 6, articulada com as políticas públicas e as expectativas quanto ao modelo de saneamento adotado no Brasil, estruturado pelo Novo Marco do Saneamento e pelos leilões. Considerando a regionalização proposta e as perspectivas para a Bacia Hidrográfica Guapi-Macacu que atende cerca de 2,5 milhões de pessoas na porção leste fluminense, o presente trabalho trata a necessidade de avanço no saneamento, a gestão e o monitoramento a partir dos indicadores de sustentabilidade, avaliar os modelos de concessão aplicados e propostos no Rio de Janeiro pelo leilão de concessão. Com o intuito de compreender as experiências e as particularidades da área de estudo, o trabalho apresenta o contexto socioambiental da BHGM e os reflexos no Sistema Imunana-Laranjal, a experiência francesa e alemã de privatização e posterior reestatização, o caso da cidade de Nova York com o Pagamento de Serviços Ambientais e a disponibilidade hídrica e os leilões de concessão de saneamento. A abordagem proposta teve como objetivo avaliar e compreender o andamento da gestão de águas considerando as suas contribuições para a sustentabilidade através das condutas dos governos e no modelo empregado na BHGM. A apropriação da natureza, as práticas, usos, cultura e percepções dos habitantes marcam a região e se apresentam através das lutas sociais como o movimento contrário à barragem proposta, projetos de reflorestamento e o debate sobre a disponibilidade e qualidade das águas na região. É analisado o processo histórico da legislação no Brasil e as medidas e ações aplicadas pelo governo no setor do saneamento, assim como o direcionamento para a privatização e se questiona nesse percurso o objetivo de universalização dos serviços e o atendimento aos ODS. / [en] The dissertation entitled sanitation management and the path to sustainability: the case of the Guapi-Macacu Watershed - RJ (BHGM) presents the need for coordination of actions in the pursuit of meeting the Sustainable Development Goals (SDGs), especially SDG 6, articulated with the public policies and expectations regarding the sanitation model adopted in Brazil, structured by the New sanitation law and the auctions. Considering the perspectives for the Guapi- Macacu Hydrographic Basin, which serves about 2.5 million people in the eastern portion of Rio de Janeiro, the present work deals with the need to advance in sanitation to evaluate the concession models applied and proposed in Rio de Janeiro by the concession auction. In order to understand the experiences and particularities of the study area, the French and German experience of privatization, the case of New York City, with the Payment of Environmental Services and the availability of water and the sanitation concession auctions. The proposed approach aimed to evaluate and understand the progress of water management, considering its contributions to sustainability through the conduct of governments and in the model used at BHGM. The appropriation of nature, practices, uses, culture and perceptions of the inhabitants mark the region and the debate on the availability and quality of water in the region. The historical process of legislation in Brazil, the measures and actions applied by the government in the sanitation sector, the direction for privatization and the objective of universalizing services are analyzed.

[pt] A gestão de recursos hídricos é uma forma de resolver os problemas em quantidade e qualidade, usos e conflitos, para atender às exigências de uma sociedade. O Estado do Amazonas, apesar de ter a maior reserva de água doce mundial, apresenta problemas significativos devido ao uso irracional e impactos ambientais. A Bacia do Tarumã-Açu está localizada há 20 km do centro urbano da Cidade de Manaus, é uma sub-bacia da Bacia Amazônica e tem como corpo hídrico principal o Rio Tarumã-Açu, afluente do Rio Negro que deságua no Rio Amazonas. Caracterizada por sua beleza cênica natural, é intensamente impactada por derramamentos de óleo de embarcações, despejo inadequado de resíduos, percolação de chorume, entre outros, fatos que motivaram os usuários a buscarem soluções, o que resultou na criação do primeiro Comitê de Bacia na Região Hidrográfica Amazônica. Esta pesquisa analisa as práticas de gestão desse Comitê e investiga a efetividade das suas ações. Foi utilizado o método de pesquisa bibliográfica e pesquisa descritiva, com partes da pesquisa aplicada, acrescida de registros fotográficos e aplicação de questionário, o que embasou um Estudo de Caso. Os resultados apontam que a gestão não atingiu a maturidade necessária para mitigar os impactos, recuperar as áreas degradadas e assegurar a sustentabilidade da Bacia. Conclui-se que a falta de recursos impulsionou a paralisação do Comitê, porém, com a intensificação da magnitude dos impactos e a resiliência do ecossistema tendendo à criticidade, a reativação do CBH Tarumã-Açu é necessária e precisa ser estruturada para cumprir a sua finalidade. / [en] The management of water resources is a way to solve problems in quantity and quality, uses and conflicts, to meet the demands of a society. The Amazonas State, despite having the largest reserves of fresh water in the world, presents significant problems due to irrational use and environmental impacts. The Tarumã-Açu Basin is located 20 km from the urban center of Manaus City, is a subbasin of the Amazon Basin and has as its main water body the Tarumã-Açu River, a tributary of the Rio Negro that flows into the Amazon River. Characterized by its natural scenic beauty, it is strongly impacted by oil spills from vessels, improper dumping of waste, percolation of slurry, among others, facts that motivated users to seek solutions, which resulted in the creation of the first Basin Committee in the Region Amazon Basin. This research analyzes the management practices of this Committee and investigates the effectiveness of its actions. We used the method of Bibliographic Research and Descriptive Research, with parts of the Applied Research, plus photographic records and questionnaire application, which was based on a Case Study. The results indicate that the management has not reached the necessary maturity to mitigate the impacts, to recover the degraded areas and to assure the sustainability of the Basin. It is concluded that the lack of resources has led to the paralysis of the Committee, but with the intensification of the magnitude of the impacts and the resilience of the ecosystem tending to criticality, the reactivation of the Tarumã-Açu CBH is necessary and needs to be structured to fulfill its purpose.

[pt] A água potável não existe mais em abundância. É preocupante verificar que o desperdício e a contaminação dos recursos hídricos ainda sejam práticas recorrentes, mesmo diante de evidências pessimistas acerca de sua disponibilidade, como observado no local escolhido para o desenvolvimento desta pesquisa. Portanto, este trabalho tem como objetivo apresentar soluções para evitar a contaminação do sistema de abastecimento, recomendar equipamentos de saneamento, sugerir um esquema de drenagem que não favoreça a proliferação de vetores de doenças, propor uma estratégia para o manejo adequado dos animais domésticos e garantir o fornecimento de água verdadeiramente potável na vila de Tanahbala, na Indonésia. O desenho metodológico está alinhado aos pressupostos da pesquisa exploratória, com a apresentação do diagnóstico local, para posterior análise quantitativa por meio da aplicação de um software de modelagem matemática, denominado Modflow 2000, versão 4.2.0.1.5.1. A ferramenta foi utilizada para visualizar o fluxo dos contaminantes no lençol freático e estimar a concentração dessas substâncias na fonte de abastecimento da vila, para posterior apresentação das sugestões de melhoria. Como resultado do diagnóstico local e dos níveis numéricos de contaminação, foi possível observar que as causas desses problemas estavam ligadas ao esgoto doméstico, à criação desordenada de animais e à proximidade de um cemitério. Sugeriu-se então algumas soluções como a realocação dos poços para captação de água, a construção de cisternas para captar água da chuva, a utilização de liners e de uma camada de geomembrana, o manejo dos dejetos da criação de animais, drenagem e soluções de saneamento. / [en] Potable water has become increasingly scarce. It is no longer an infinitely renewable resource as we once thought it was. However, it is not unusual to see hydric resources being wasted or contaminated – despite all the pessimistic forecasts regarding its availability for the future generations. Actually, lack of water is not a far-fetched problem anymore. Around 1.6 billion people rely on insufficient hydric resources. By 2020, this number will double: there will be about 3 billion people with insufficient access to drinking water (Boff, 2005). The central theme of the present research deals with the problems provoked by an inefficient management of hydric resources. Its aim is to provide alternatives for managing water in the small and remote village of Tanahbala, in Indonesia. In this distant town, solutions which might be feasible elsewhere do not always prove to be possible. In order to provide potable water for the villagers in Tanahbala, it is crucial to overcome three main obstacles: 1) the inappropriate disposal of domestic sewage; 2) the lack of livestock management; and 3) the contamination provoked by a neighboring cemetery. So as to address these problems, the present study has pointed out a few measures, such as the replacement of water wells, the construction of tanks for catching and storing rainwater, the use of liners and a layer of geomembrane, the appropriate management of the animals excrement, as well as many other sanitary solutions. All these recommendations attempt to meet the village s needs without requiring a sophisticated infrastructure – which is not within the villagers reach at the present time. According to data from the World Health Organization (WHO) and UNICEF (2004), 1.1 billion people around the world do not have access to pure water. In the meantime, 2.6 billions do not live in areas with adequate sewage. Tanahbala, the place studied in this research, is just one more item in the apparently endless list of locations deprived from essential resources such as water. The troublesome water distribution and sewage treatment has a significant impact on mortality rates. All over the world, from four to six thousand children die everyday because of diseases associated to the lack of potable water or inadequate sewage treatment (WSSCC, 2011). In Indonesia, an impressive number of people live below the poverty line. In these lower social layers, the lack of potable water remains the most prominent health problem. The reasons behind this problem are the geographic aspects of Indonesia and the precariousness of the infrastructure used to distribute water. Quite differently from continental areas, Indonesia does not have the means to create a centralized water distribution system. Formed by thousands of islands, the country has to delegate to each one of them the management and the treatment of hydric resources. This is the reason why the population of Indonesia has suffered from a number of diarrheic diseases caused by contaminated water. No wonder diarrhea is still ranked among the ten main causes of deaths in Indonesia (WHO/ UNICEF, 2004). In fact, chronic infectious diarrhea has been detected in 66.7 per cent of the population. Based on this information, it is unavoidable to come to the conclusion that both, the treatment and the distribution of water in Indonesia, are quite far from the minimum security standards. Hence, it is clearly urgent to develop strategies to meet the population s needs, especially in the most distant islands, where potable water is still a far-fetched dream. In Indonesia, underground water is normally good from a microbiological viewpoint. The problem is that it is easily contaminated due to the emission of pollutants from homes, factories, plantations and even cemeteries. The present research focuses on specific types of water pollution: the contamination provoked by cemeteries, livestock and domestic sewage. The first part of this research has been developed by means of observing the region and collecting documents on the governmental database, so that the local characteristics could be thoroughly understood. The methodological design adopted, therefore, is in line with what is called exploratory research. In the engineering field, exploratory research is particularly useful when it is necessary to estimate the feasibility and the costs of a given project. The scope of the present research is precisely that: the aim is to provide a solid ground for the development of future research that might work on a more definite solution for the hydric resources in Tanahbala. First, this research presents a diagnosis of the local situation. Afterwards, a quantitative analysis is carried out with the help of a mathematical modeling software called Modflow 2000, version 4.2.0.1.5.1. This tool has been used to visualize the flow of contaminants in the underground water, as well as to estimate the concentration of substances in the water supply used by those who inhabit Tanahbala. In the end, this study recommends some improvements, without disregarding the limited resources and the precarious infrastructure available in the village. The inappropriate location of the cemetery and the careless management of livestock are not the only threats to the quality of the soil and the water in Tanahbala. The population is also used to bathing in public water sources, which certainly worsens the contamination problem. Raw sewage and animals surround the village, forming a single nucleus of contamination. The cemetery is on the left side of the entrance of the village. In addition to that, the well that supplies water to Tanahbala is dangerously close to the contaminated areas. Occasional earthquakes and tsunamis add chaos to a situation which is already quite precarious. In 2004, Indonesia was hit by a devastating tsunami, whose tragic effects were also felt in Tanahbala. A great part of the village lies on a type of soil that is mostly sandy, favoring the penetration of pollutants, due to its high permeability level. This characteristic increases considerably the risks of underground water contamination. The toxic fluids that come from the decomposition of corpses are the main cause of environmental pollution provoked by cemeteries. The crucial challenge is to stop them fluid from infiltrating into the soil and contaminating underground water. Liners are layers of low permeability formed by natural, artificial or a combination of both materials. The objective of these layers is to protect a given area from the infiltration of harmful fluids. One of its essential features is also the capacity of removing impurities. The use of liners is very common in sandy soils, where their efficiency is out of question. When used in this type of soil, the liners manage to reduce significantly the permeability level. Moreover, it is a low cost alternative, since it does not require the employment of higher technologies. The combination of these characteristics seems to point out the use of liners as the ideal option for protecting the inhabitants of Tanahbala against the hazardous substances that come from the cemetery. Geomembranes may also be an important ally. They are impermeable synthetic barriers, quite resistant from a physical and chemical point of view, and with low hydraulic conductivity. They are commonly used to stop leachate from migrating into the soil or underground water. Because they are susceptible to flaws, geomembranes should not be the only mechanism of protection. It is fundamental to rely on a more complete system of isolation. Taking into account the peculiarities of the Indonesian context, the present research recommends the use of a geomembrane and a liner formed by soil, cement and quicklime. Domestic sewage contains pathogens that cause several diseases, such as typhoid, infectious diarrhea and amebiasis. In Tanahbala, sewage is generally left on the soil, contributing to the dissemination of a wide variety of diseases. Besides, both superficial and underground water quality tends to be altered by this kind of contamination. The main consequences are a change in the color and in the smell of water, as well as a considerable reduction in the concentration of oxygen. The water pollution triggered by the lack of adequate sewage treatment is also harmful for the local environment, putting at stake the survival of animals and vegetation in the Indonesian village. The position of the wells in relation to the main points where contamination by sewage happens is also a fundamental aspect. In Tanahbala, the wells that provide drinking water for the houses are dangerously located downstream in relation to the places where contamination occurs. The solution is quite simple: repositioning these wells and placing them upstream is an essential step in order to improve the quality of the water available to the villagers. In addition, it is essential to construct a septic tank where sewage can be disposed and decomposed by anaerobic bacteria. The present research has used the Brazilian standards to suggest the measures for the Indonesian septic tank. However, in further studies, it is important to use local data to design the ideal system for the villagers in Tanahbala. Placing tanks to catch and store rainwater is an intelligent and inexpensive measure. With the high rainfall rates in Indonesia, this option seems to be very promising. As long as these tanks remain protected, the water stored by them is harmless. The choice of the material for the tank is also relevant. Cement lasts longer. However, if it is difficult to transport this material to Tanahbala, plastic tanks might be a better option. The construction of dungyards seems to be the most appropriate option for the population in Tanahbala. Besides presenting low costs, they are easily managed. The excrement kept in these dungyards remains there for 120 days. Throughout this period, organic matter becomes stable and the pathogens in it are deactivated. Composting is also a worthwhile alternative; after all, this process is able to reduce the bad smell and the proliferation of hazardous microorganisms. On top of that, composting turns useless ordure into a valuable commodity: manure, which is quite useful as a fertilizer. The main challenges regarding the use of composting have to do with handling three variables – humidity, aeration and temperature. The creation of an efficient draining system is essential and challenging at the same time. The first difficulty has to do with handling the rainwater that accumulates on the ground. When the draining system does not work properly, the population suffers from a number of problems, such as floods and diseases related to the uncontrolled accumulation of water: diarrhea, typhoid, leptospirosis and malaria are some of the illnesses that become widespread once draining is not efficient. In addition, humid soils provide a longer life for microorganisms. Thus, draining is an important tool when it comes to reducing the contamination of the soil by pathogens. In Tanahbala, specifically, it is recommended to adopt a microdraining system that combines three modalities: superficial, underground and vertical.Counting on appropriate equipment is not enough when the population is not aware of its environmental and sanitary responsibilities. Therefore, it is fundamental to raise people s awareness on the importance of adopting new hygiene habits and helping protect the environment.

[pt] A previsão dos efeitos poluidores sobre uma bacia hidrográfica é uma constante necessidade para os órgãos de gestão ambiental e para os tomadores de decisão neste âmbito. Dentro deste contexto, os modelos matemáticos que permitam prever danos ou melhorias na qualidade de água de bacias hidrográficas são importantes ferramentas para este fim. O Qual2E desponta como uma destas ferramentas, de acesso livre, aplicável à sistemas fluviais, unidimensionais, bem misturados e de fluxo constante. Este trabalho propõe uma aplicação do Qual2E para o rio Corumbataí, localizado no interior do Estado de São Paulo, visando a obtenção de uma curva representativa para a qualidade de água do rio. Para tal, foi utilizada a metodologia sugerida pelo modelo, que prevê a divisão do sistema em trechos de características hidráulicas semelhantes e a subdivisão desses trechos em elementos de mesma extensão - os elementos computacionais (ECs). Os dados de vazão, profundidade, concentração de OD (oxigênio dissolvido), DBO (demanda bioquímica de oxigênio), temperatura, carga e localização de fontes poluidoras foram obtidos através de um projeto de parceria da CETESB com a USP, que contempla a elaboração de um banco de dados para qualidade de água da bacia. Este banco, georreferenciado, foi utilizado tanto para a entrada de condições iniciais no modelo,como para a construção da curva de referência dos dados reais de campo, para comparação com a curva calculada pelo modelo. Os coeficientes de reação - resultantes da interação entre as variáveis OD e DBO - presentes no sistema de equações diferenciais resolvidas pelo modelo, foram estimados através de tentativa e erro, até a concordância com os dados observados. A calibração efetuada se mostrou eficiente em reproduzir os dados observados, validando os parâmetros estimados através de um outro conjunto de dados.Uma análise de sensibilidade foi realizada para os parâmetros k1,k2,k3 e k4 e a curva calculada foi mais sensível ao coeficiente de decaimento de DBO. As limitações inerentes ao modelo, à coleta de dados e ao tratamento estatístico dos dados disponíveis impediram uma melhor concordância da curva calculada com a observada. / [en] The forecast of the polluting effects over a hydric basin is a constant need for the official environmental managers and for the people responsible for the decisions in this subject. Therefore, mathematical models that allow forecast damages or improvements in the river basin water quality are important tools for this purpose. Qual2E appears as one of these tools, of free access, and suitable for one-dimensional well-mixed rivers with constant flow. The objective of this work is to apply the Qual2E model to Corumbataí River, located in São Paulo State, in order to obtain a representative curve of the river water quality. The method suggested by the model request the division of the river in reaches with similar hydric features and a subdivision of these reaches in computational elements (CEs) with the same extension. The flow data, depth, DO (Dissolved Oxygen) concentration, BOD (Biochemical Oxygen Demand), temperature, load and location of pollution sources were obtained from a joint project between CETESB and USP, that resulted in a database for the water quality of the basin. This geo-referenced database was used both for the initial conditions to the model, as for the determination of a reference curve with the real field data, for comparison with the calculated curve of the model. The reaction coefficients - resulting from the interaction between DO and BOD - are the constants of the differential equations system solved by the model, were estimated through trial and error, until the agreement with the observed data. The calibration was efficient to reproduce the field data, through the validation for another group of data. A sensitivity analysis was executed for the parameters k1, k2, k3 and k4 and the calculated curve seemed to be more sensible to the BOD decaying coefficient. The limitations inherent to the model, the data collecting and the statistical treatment of the available data did not allow a better agreement between the calculated and the observed curves.

[pt] A qualidade das águas dos corpos hídricos nas áreas urbanas é normalmente comprometida em função da grande quantidade de lançamento de esgotos com ou sem tratamento inadequado, trazendo impactos ambientais, econômicos e sociais. Esta pesquisa tem o objetivo de analisar a capacidade de gestão e os arranjos de governança de instituições e agentes públicos responsáveis pelo saneamento do complexo lagunar de Jacarepaguá e a existência de um arcabouço de leis ambientais. A partir da revisão bibliográfica pesquisou-se o histórico da ocupação e do desenvolvimento da infraestrutura urbana da região onde está situado o complexo lagunar. Os boletins da qualidade das águas das lagoas e rios foram levantados do período de 2013 a 2019. Os resultados obtidos são comparados com os resultados de estudos científicos realizados com dados que retroagem ao início dos anos 80. A legislação das matérias de recursos hídricos e saneamento foram pesquisadas com objetivo de identificar as atribuições dos atores envolvidos. Constatou-se que as águas do complexo lagunar apresentam um alto grau de poluição com enorme aporte de esgoto in natura e que as causas são as consequências de irresponsabilidade e omissão dos diversos atores que atuam no planejamento, na fiscalização, na regulação, no controle e na prestação dos serviços de esgotamento sanitário. Somam-se a isso um conflito de competência entre o Estado e o Município, ocupações irregulares e o mau funcionamento de instalações privadas. / [en] The major economy of the city of Rio de Janeiro is tied into its tourism and leisure industry, due to its unique natural beauty of its landscape. The unique combination of mountains meeting the sea has earned it the title given by UNESCO of the First Urban and Cultural Landscape declared World Heritage. This takes into consideration the area s natural and urban monuments of the South zone, in particular, but recognizes the unique relationship between man and nature, and the balance between natural and man-made elements. It considers the environmental and social interaction, which enables its citizens to enjoy various forms of leisure activities associated with the area s unique natural beauty. However, despite this designation, on the west side of the city, there are found other natural beauties, including the coastal lagoons of the Jacarepaguá lagoon system. But here, the environment has been completely neglected by the government. In these lagoons, people cannot fish, sail, or swim. The use of these ecological sites is prohibited due to the contamination of the waters. A natural heritage for all, the waters have become degraded with the presence of raw sewage, which causes the foul smell, disease, and the reduced presence of fauna and flora. Unregulated construction on its banks and on the edges of its tributaries has caused these bodies of water to become filled with garbage, sand, and all sorts of debris, besides the sewage. From its primitive origin until the implementation of the Urbanist Lúcio Costa s plan, the region remained preserved. Corrêa (1933), testified crystal clear water lagoons and flooded green fields where fishing, hunting, and natural resources were abundant. However, even at this early date, he observed the degradation of forests and the hunting of animals out of control, and recorded a lack of regulation by the governing body, the Water and Sewage Inspectorate. He therefore suggested, inspired by the laws of the Office International pour la Protection de la Nature, the creation of a biological reserve for Marapendi lagoon, realized in 1965.