The studies in this dissertation address the issue of variability in runoff generation and pollutant concentration in urban areas, and specifically in the catchments of stormwater control measures. There is an imperfect correlation between runoff volumes and the capture area and land uses of urban catchments. Variable capture areas and uncertainty in urban runoff sources complicate stormwater control measure design and urban stream assessment. Four stormwater control measures in upstream suburban Philadelphia, ranging in capture area from 0.11 ha to 32 ha, were monitored, sampled, and modeled. Sampling was conducted in the watersheds of Wissahickon Creek, Tookany Creek, and Pennypack Creek. The approaches discussed below have the goal of better understanding runoff and the movement of associated contaminants into stormwater retention basins and streams. Rather than viewing runoff generation and contaminant transport as a static process, this work proposes that the amount of runoff contributed from different areas of a catchment changes during and between storm events, and that the origin and concentration of contaminants change as a result. Linking source areas to runoff volumes through natural and modeled tracers could improve predictions of water quality and quantity in stormwater control measures in urban streams. Nitrate (NO3–) isotope ratios were used as tracer of flow from different urban land uses. Time series samples of stormwater runoff entering two stormwater control measures (a constructed wetland and a small bioretention basin) were collected and analyzed to distinguish sources of NO3– by samples’ δ15N and δ18O ratios. A Bayesian mixing model was used to determine that NO3– sources were a mix of soil nitrogen (N) and atmospheric deposition across six storm events. Furthermore, atmospheric versus soil N sources varied throughout the storms. The large catchment of the constructed wetland had more NO3– source variability between samples compared to the small catchment of the bioretention basin. Thus, the NO3– isotopes suggest more distinct flow paths in the large catchment and more mixing of flow across land uses in the small catchment. Quantifying flow path variability from storm to storm and between different catchments can improve design and placement of urban stormwater control measures. A distributed hydrologic model, GSSHA, was used to simulate overland runoff from impervious and semi-pervious land covers in the catchment of a stormwater control measure. The positions of low vegetation and impervious land uses over the catchment were rearranged to create hypothetical catchments during four storm events. Fluctuating source proportions over time suggested that grab samples might not be adequate for capturing average overland runoff chemistry. It was also found that the portion of total runoff volume from impervious areas varied from 50 to 75% while the relative proportion of impervious cover remained constant at 54%. Land use percentages averaged over capture areas are frequently used to estimate runoff amounts and pollutant concentrations, but this model disrupts the assumption that urban hydrologic responses can be predicted from imperviousness alone. Overland runoff was measured and modeled before and after the installation of two stormwater control measures, a berm and a bioswale. Discharge in the stream was modeled for 9 storms ranging in size from 14 to 54 mm. We found that during 4 of the modeled storms there was no decrease in stream discharge and decreases in discharge were generally only observed for low intensity storms. Furthermore, only 5% of the stream catchment was captured by SCMs. Modeled tracers, used to track runoff contributions from areas upslope of the SCMs found that the size of upslope contributing areas did not predict the proportion of runoff generated in each area. Field data to support the models included water level loggers and samples of overland runoff collected in subsurface stormwater casing. After the SCMs were installed, less water was captured in downslope sampling bottles, but new flow paths developed. Furthermore, significant variation was observed in upslope concentrations of dissolved nutrients and total suspended solids, casting doubt on whether point samples of urban overland runoff geochemistry can be representative given variable runoff generation and heterogeneous land uses. This study points out the challenges in evaluating stormwater control measures and reveals that source areas’ contribution to stream flow varies independently of their size. Therefore, modeling before stormwater control measure installation is recommended to determine the factors that influence a capture area’s contribution to urban streamflow. / Geoscience

Forecasted changes to climate and land use were used to model variations in the streamflow characteristics of Occoquan watershed and water quality in the Occoquan reservoir. The combination of these two driving forces has created four themes and an integrated complexly-linked watershed-reservoir model was used to run the simulations. Two emission scenarios from the fourth assessment report of the Intergovernmental Panel on Climate Change (IPCC), along with four General Circulation Models (GCMs) by using two statistical downscaling methods, were applied to drive the Hydrological Simulation Program - Fortran (HSPF) and CE-QUAL-W2 (W2) in two future time periods (2046-2065 and 2081-2100). Incorporation of these factors yielded 68 simulation models which were compared with historical streamflow and water quality data from the late 20th century. Climate change is projected to increase surface air temperature and precipitation depth in the study area in the future. Using climate change only, an increase in high and median flows and decrease in low flows are projected. Changes in flow characteristics are more pronounced when only future land use changes are considered, with increases in high, median and low flows. Under the joint examination of the driving forces, an amplifying effect on the high flows and median flows observed. In contrast, climate change is projected to dampen the extreme increases in the low flows created by the land use change. Surface water temperatures are projected to increase as a result of climate change in the Occoquan reservoir, while these changes are not very noticeable under the effect of land use change only. It is expected that higher water temperatures will promote decreased oxygen solubility and greater heterotrophy. Moreover, longer anoxic conditions are projected at the bottom of the reservoir. Results indicate that higher water temperature will increase the denitrifying capacity of the reservoir, especially during summer months, further reducing the nitrate concentration in the reservoir. / PHD / Water resources managers are facing a new set of challenges of developing strategies to address the regional impacts of climate change and land use change, especially in metropolitan areas. Simulating climate change and land use change scenarios can shed light on mitigation and adaption approaches for water resources management as well as future designs (for example, infrastructure, agriculture, irrigation, etc. among other sectors). The focus of this study is the Occoquan watershed with an area of 1530 km² (590 square miles) which includes the 1700-acre Occoquan reservoir that yields about 40% of the drinking water supply of near 2.0 million residents in northern Virginia. The Occoquan watershed located approximately 40 km to the southwest of Washington, D.C. and is situated in the Mid-Atlantic region of the United Sates with four distinct seasons and is part of a bigger watershed known as the Potomac River Watershed. The primary aim of this research is to provide an improved, quantitative understanding of the potential impacts of climate change and land use change on the Occoquan watershed. The findings of this research can benefit future water supply reliability and mitigation strategies in the study area considering this watershed’s essential role as a water supplier in northern Virginia.

Thesis (MDF)--University of Stellenbosch, 2010. / The Southern Africa Development Community (SADC) Treaty aims at achieving regional integration, poverty alleviation and economic growth. Water is a catalyst to these aims, thus making it key for the region to manage and develop water resources. Water in the SADC region is a shared resource among the countries, making joint development of the resource important for peace and prosperity. SADC has been promoting transboundary water resources management among its member states. The region has done a lot of work in establishing an enabling environment for the management of water resources. The SADC Protocol for Shared Watercourses (the “Watercourses Protocol”), the Regional Water Policy (the “Water Policy”) and the Regional Water Strategy (the “Water Strategy”) are all instruments that have been developed to support the management of water resources. However, the region remains heavily under-developed in terms of water infrastructure and in order for the region to develop its water resources, the SADC secretariat has developed a Regional Strategic Water Infrastructure Development Programme (referred to as the “SADC Programme for water infrastructure development” in this study). The Programme is aimed at responding to the lack of infrastructural development in the region and identifies regional water projects to be implemented. Water is a sector that struggles in attracting private sector funding and involvement. This study aims to look into ways that the private sector can been attracted to participate in the Programme for water infrastructure development and also proposes ways they can be engaged. Private-sector involvement varies from project identification to project implementation and funding. To attract the private sector to participate in the SADC Programme for water infrastructure development, SADC and the member states have to build on the enabling environment established in the region and also on relationships based on existing institutions. The private sector needs to be assured of good market potential and sound financial returns. This can be achieved if the region better co-ordinates the prioritization of regional projects through integrated planning. NEPAD and SADC working closely together, to issue that a consistent development agenda is communicated to potential investors, could add value and avoid duplication. It is also important to link to national development priorities in order to ensure that local issues are addressed. Capacity of the public sector to support regional projects is also important – capacity to develop bankable projects, develop financing mechanisms and to implement the projects is required at all levels. The SADC region lacks capacity to participate in complex infrastructure projects and this has to be addressed through establishing a Private Public Partnership Unit at the SADC Secretariat. Capacity to also manage and regulate water services is lacking in a number of countries in the region. These are important issues to ensure fair pricing and to give the private sector confidence on issues of tariff setting. To attract private funding into the water sector the region needs to develop innovative financing mechanisms in order to leverage market-based repayable finance. In the implementation of the SADC Programme for water infrastructure development there is a need to evaluate various types of innovative financial instruments and assess their potential use for regional water projects. Local capital markets in a number of the countries are weak, therefore the implementation of the SADC Protocol on Finance and Investment (the “Finance Protocol”) is important in strengthening these markets. Political will and good governance within member states are also important in attracting investors. SADC as the promoter of infrastructure policies in the region should play a proactive role in encouraging its member states to observe the rule of law and also to use existing treaties within SADC to ensure countries do so. Poor governance and unstable economies are a disincentive for private sector involvement.

<p>Management of water bodies according to their river basinsis becoming increasingly common, as the concept of IntegratedWater Resources Management (IWRM) is getting more and moreacknowl-edged. In Europe, a large portion of these“new”management units will probably be internationalor transboundary. Decisions and policies consideringtransboundary water issues need to be based on reliable andcomprehendible information. In this thesis, a review of variousexisting models that may be used for understanding the role anduse of information in (transboundary) water management ispresented. Further, the thesis reports on an assessment of theinformation management of three transboundary water regimes inEurope, namely the international water commissions for LakeNeusiedl, Lake Constance and Elbe River. Besides examining theinformation management of the regimes as such, the managementwas also related to information needs implied by the IWRMcon-cept and by the EU Water Framework Directive (WFD). Thereviewed models and approaches were grouped into threecategories: information management models, information cyclemodels and communication between actors. The first categorycomprised models that may be used for managing and assessingdifferent types of information. The second group dealt withmodels explaining the production and communication ofinformation predominately from an information producer/senderperspective. The third group focused on ideas concerninginteractions and communication of information between differentkinds of actors. The studies on information management intransboundary water regimes showed that the information needsand strategies often were defined primarily with watercommissions’own needs in mind. The data collected by thecommissions were predominated by monitoring data, describingthe status of the environment and the impact caused by humanactivities. Furthermore, any communication of information toother groups of actors was mainly done through passivechannels. The information management in these transboundarywater regimes was not fully in accordance with informationneeds implied by the IWRM concept and the EU WFD.</p><p><b>Keywords:</b>Integrated Water Resources Management (IWRM);transboundary water management; information; EU Water FrameworkDirective (WFD); regimes; policy and decision making; LakeNeusiedl; Lake Constance; Elbe River.</p>

In this minithesis I have investigated overlapping mandates as a source of management failure in water management in South Africa in general and Eerste River Catchment in particular. I analysed major legislation which deals with water management to find out how duties and responsibilities are apportioned in the various pieces of legislation. I also undertook an exercise of evaluating roles and responsibilities played by various organs of state in water management from national government, Provincial Government of the Western Cape through to local government, in this case the Municipality of Stellenbosch and the City of Cape Town. It emerged that there were a number of areas of overlap, ambiguously defined mandates, conflict and that these were impeding on decision making in water management. In order to test the framework built above, I then applied it in the Plankenbrug River, a tributary of the Eerste River. Through analysis of newspaper clippings over a period of 4 years I was able to reconstruct conflict over ill-defined mandates in the various aspects of the management of the catchment which showed that<br /> there were differences in roles of the different state organs operating in the catchment. Water management conflict emanated from lack of congruence in the various legislation and differences in the interpretation of legislation. The various state organs seem to be aware of the constitutional duty of cooperative government that engenders state organs to work co-operatively in order to meet their developmental mandates. It seems however that the state organs were merely interested to be seen to be in conformity with this duty more than actually solving the issue as this was seen as something to be tackled at a higher level.

The availability and management of water resources is a global issue, this is particularly true in countries with limited water resources, such as Palestine, which falls under the Water Stress Line (1000 m3/person/year)1. Palestine has operated under an -unstable political, economic and social conditions for more than six decades. This uncertainty has resulted in mismanagement, inefficient institutions and the over-xploitation of water resources. The main aim of this study was to produce socioeconomic indicators based on the water tariff structure in order to be pro-poor and to enable water utilities to cope with uncertainties. The study s recommendation is for a flexible, pro-poor and socially acceptable tariff structure have been based on empirical work and socio-economic data which has been collected by rigorous research and reinforced with case studies. Initial results based on a pilot survey showed that there was a 33% increase in the revenue of the water supplier equivalent to 13% of the total water costs and an increase in the number of beneficiaries that paid their bills ranging from 10.5% to 38.6%. If applied at national level, the model application based on current socioeconomic data would have a wide positive socio-economic impact in reducing poverty, financial equality, social security and reduction of the effect of uncertainties. The reform of the existing legal and institution framework are a prerequisite for the application of this kind of model. Institutional and legal reforms coupled with the application of this model, would produce a dynamic water pricing policy as part of the efforts to have an integrated water management and would serve as a tool for the national goal of poverty alleviation and food security.

Orientador: Cláudio Antonio Di Mauro / Resumo: O presente trabalho tem como objetivo compreender a forma como é realizada a fiscalização dos usos dos recursos hídricos no estado de São Paulo. Especificamente, busca demonstrar quais são os procedimentos adotados para a fiscalização e quais órgãos e estruturas estão envolvidos nesse processo. Outrossim, almeja apontar presumíveis dificuldades que limitam as ações fiscalizadoras e possíveis variações dessas ações em diferentes Diretorias de Bacias Hidrográficas, em função de suas peculiaridades regionais. Parte da hipótese de que a fiscalização dos usos de recursos hídricos não produz o resultado esperado, conforme preceitua a legislação vigente. Justifica-se pelo fato de que a fiscalização é um instrumento fundamental para a implantação das Políticas Nacional e Estadual de Recursos hídricos. Para a realização desta pesquisa foi adotada como área de estudo a Diretoria de Bacia do Peixe Paranapanema, componente do Departamento de Águas e Energia Elétrica (DAEE), porém, para otimizar o alcance dos objetivos foi estendida às Diretorias de Bacias do Médio Tietê e do Ribeira de Iguape e Litoral Sul. Os recursos metodológicos utilizados foram as pesquisas exploratória e qualitativa, associadas as pesquisas documental e bibliográficas, além de entrevista semiestruturada. Os resultados apontam que não existem padrões estabelecidos para as ações fiscalizadoras dos usos de recursos hídricos, que existem dificuldades limitadoras e variação das ações nas Diretorias de Bacias; sugerindo ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this work is to understand the way how it is done the fiscalization of the uses of water resources in the state of São Paulo. Specifically, it seeks to demonstrate the procedures adopted for inspection and which bodies and structures are involved in this process. Moreover, it aims to point out presumed difficulties that limit inspection actions and possible variations of these actions in different Watershed Directories, due to their regional peculiarities. It starts from the hypothesis that the supervision of the use of water resources does not produce the expected result, according to the current legislation. It is justified by the fact that supervision is a fundamental instrument for the implementation of National and State Water Resources Policies. To carry out this research, the Peixe Paranapanema Basin Directorate, a component of the Department of Water and Electric Energy (DAEE), was adopted as a study area. However, to optimize the achievement of the objectives, it was extended to the Basin Directorates Médio Tietê and the Basin Directorates of the Ribeira de Iguape e Litoral Sul. The methodological resources used were exploratory and qualitative research, associated with documentary and bibliographic research, as well as semi-structured interviews. The results indicate that there are no established standards for actions to supervise the use of water resources, that there are limiting difficulties and variation of actions in the Basin Directorates; sug... (Complete abstract click electronic access below) / Mestre

Recente aprovação da Lei 11.445/2007, que estabelece as diretrizes nacionais para o saneamento básico e para a política federal de saneamento básico representa um avanço para o estabelecimento de um marco regulatório no saneamento no Brasil (SNSA, 2009), considerando o passivo do setor no país. Dentre outros instrumentos, tal lei prevê a elaboração de planos municipais de saneamento, que devem ser elaborados e editados pelo titular do serviço, compatíveis com os planos de bacia hidrográfica no qual está inserido e garantir o controle social na gestão dos serviços de saneamento em consonância com os princípios da lei: universalização do acesso, integralidade e intersetorialidade das ações e participação social. Neste sentido, objetivou-se identificar e avaliar a integração entre as políticas de Saneamento e de Recursos Hídricos na bacia hidrográfica dos rios Sorocaba e Médio Tietê e sua contribuição para a governança da água. O foco da pesquisa foi a gestão integrada do saneamento ambiental e dos recursos hídricos, na qual são de particular importância os processos institucionais qualificados pelo termo governança da água e seus princípios: descentralização, participação, integração e equidade. Foi contextualizado o quadro institucional e os atores envolvidos no processo de gestão em saneamento e recursos hídricos; feito um diagnóstico legal e normativo e de saneamento e recursos hídricos na localidade; e o levantamento dos instrumentos de gestão dos setores recursos hídricos e saneamento; e atores-chave foram entrevistados. Foram analisados os componentes integração e controle social nos planos de bacia e de saneamento; e discutido o alcance desses aspectos para a governança da água. Concluiu-se que o Comitê de Bacia desempenhou um papel central na promoção da integração entre as políticas de saneamento e de recursos hídricos; e que o controle social e a participação contribuem para a integração entre setores relacionados aos recursos hídricos e saneamento. / The Law 11.445/2007 for sanitation sector was approved recently in Brazil, which establishes national guidelines for sanitation and federal policy sanitation. This represents a step towards in establishing a regulatory framework for sanitation in Brazil (SNSA, 2009). The Law 11.445/2007 places itself as an instrument of the elaboration of Sanitation Municipal Plans. These Plans must be elaborated by the service´s titular; consistent with the Watershed Plans; and guarantied social control in sanitation services management; in consonance with Law´s principles: universalization of access, integrality and intersectoral aspect of actions and social participation. In this sense, this study aimed to identify and evaluate integration between Sanitation and Water Resources policies in Sorocaba and Médio Tietê catchment; and its contribution to water governance. This research focused on sanitation and water resources integrated management in which is particularly important institutional processes qualified by water governance term and its principles: decentralization, participation, integration and equity. The methodological steps were: contextualization of institutional frame and social actors involved on this process; diagnostic of legal and normative aspects of sanitation and water resources of locality; research of management instruments of the studies sectors; and interview of key-actors. Integration and Social Control were analyzed on Sanitation Municipal Plans; and discussed range of integration of these aspects to water governance. This study concludes that the River Basin Commission played an important role to promote integration between water resources and water and sanitation policies; and social control and public also contributes to integration of sectors related to water resources.

O Projeto Mogi-Guaçu - inserido no Programa Petrobrás Ambiental, além de possuir características socioambientais e uma abordagem multidisciplinar, teve a finalidade de desenvolver ações que promovessem a redução dos impactos ambientais em 18 municípios nos Estados de Minas Gerais e São Paulo auxiliando na mitigação dos conflitos pelos usos múltiplos da água e na proteção dos corpos d\'água. O projeto envolveu mais de 20 mil pessoas e foi organizado em vários núcleos de ação, conforme as áreas de trabalho: Educação Ambiental, Recursos Hídricos, Saneamento Básico Rural, Agricultura, Vegetação, Piscicultura, Turismo, Transferência Tecnológica e Apoio à Sociedade Civil Organizada. Este trabalho buscou propor uma metodologia que avalie as ações, resultados e os reflexos decorrentes de um projeto socioambiental. A metodologia proposta abrange uma pesquisa bibliográfica, o reconhecimento da região e a aplicação de questionários e entrevistas em uma amostragem dos envolvidos no Projeto. Os resultados revelaram a grande importância do Projeto junto à comunidade local e 86,5% declararam estar satisfeitos com as atividades desenvolvidas. Entretanto, 72,7% consideraram seu período de realização muito curto e que 83,7% ressaltam a necessidade de continuidade. Este trabalho trouxe como principal contribuição a proposição de ferramentas que podem ser empregadas em avaliações contínuas no sentido de melhorar os projetos e programas socioambientais, para substanciar ações mais efetivas, com resultados que sirvam não somente como instrumento de controle dos financiadores, que às vezes os percebem como mera formalidade, mas possibilitando um redirecionamento dos processos de intervenção, cumprindo o estabelecido na Política Nacional de Educação Ambiental. Algumas universidades têm fomentado o desenvolvimento de pesquisas que têm favorecido e democratizado o conhecimento à população local por meio da extensão acadêmica. Portanto, fez-se necessário avaliar, continuamente durante sua execução, as ações desenvolvidas em diferentes projetos, analisando se a academia está desenvolvendo o importante papel da extensão universitária, com vistas a melhorar o contato da Universidade com a Sociedade na qual ela se insere. / The Mogi-Guaçu Project - inserted in the Petrobras Environmental Program - as well as social-environmental characteristics and a multidisciplinary approach, aimed to develop actions that promote the reduction of environmental impacts in 18 cities in Minas Gerais and São Paulo assisting in the mitigating of conflicts over multiple uses of water and protection of water bodies. The project involved more than 20,000 people and was organized into several units of action, as the work areas: Environmental Education, Water Resources, Rural Sanitation, Agriculture, Vegetation, Fish Farming, Tourism, Technology Transfer and Support to Civil Society Organizations. This study attempts to propose a methodology to assess the activities, results and reflections resulting from an social - environmental project. The methodology includes a literature search, recognition of the region and the use of questionnaires and interviews in a sample of those involved in the project. The results describe the great importance of the project with the local community (86.5%) reported being satisfied with the activities. However, 72.7% considered their very short period of achievement and 83,7% emphasize the need for continuity. This work brought the main contribution proposing tools that can be used in ongoing evaluations, improving the social and environmental projects and programs, to substantiate more effective actions, with results that will serve not only as an instrument of control of the lenders, who sometimes perceived as a mere formality, but allowing a redirection of the intervention processes, meeting the provisions in the National Environmental Education. Some universities have encouraged the development of research that has democratized knowledge and favored the local population through the academic extension. Therefore, it was necessary to continually evaluate during their execution, the actions performed in different projects, analyzing if the academy is developing the important role of knowledge transmission, in order to improve the contact of the university with the society.

No Brasil, a Política Nacional de Recursos Hídricos apresenta a cobrança pelo uso da água como um instrumento de gestão de recursos hídricos de caráter econômico. Considerando esse caráter, a cobrança deve ter como objetivos: racionalizar o uso do recurso baseado na sua escassez; reconhecer a água como um bem de valor econômico, refletindo os custos ambientais advindos de sua utilização; e diminuir os conflitos entre os usos, induzindo uma alocação que considere o gerenciamento da demanda e as prioridades da sociedade. Além dessas metas, como instrumento de gestão de uma política que lista como primeiro objetivo \"assegurar à atual e às futuras gerações a necessária disponibilidade de água, em padrões de qualidade adequados aos respectivos usos\", a cobrança deve ser implementada de maneira que o agente usuário direcione seu comportamento no sentido da sustentabilidade ambiental. Mediante esses fundamentos, o que se pretende desenvolver neste trabalho é a aplicação de um modelo de cobrança sobre o uso da água que considera como princípio base a manutenção da qualidade ambiental medida pela adequada gestão da escassez de água e, compondo a busca dessa qualidade, a racionalização econômica e a viabilização financeira. Essa predominância do ambiente sobre aspectos econômicos vem no sentido de desqualificar argumentos segundo os quais, os impactos advindos dos usos da água serão corrigidos indefinidamente mediante investimentos financeiros em infra estrutura. Admitir que o desenvolvimento tem esse poder é supor equivocadamente que o meio econômico é limitante do meio ambiente e não o contrário. Esta constatação mostra qual é o problema da maioria das propostas de cobrança que valoram a água baseadas em custos de tratamento de resíduos e de obras hidráulicas. Por mais elaborados que sejam essas fórmulas de cobrança, chegando a ponto de se conseguir que fique mais caro, mediante um padrão ambiental corretamente definido, captar água ou lançar poluentes do que racionalizar usos, o preço da água não pode estar baseado em fatores cuja \"sustentabilidade\" pode acabar no curto prazo, dependendo do ritmo de crescimento econômico. A sustentabilidade dos recursos hídricos só será base da cobrança pelo uso da água se o valor cobrado for dificultando esse uso à medida que os recursos tornarem se escassos, e não quando os custos de medidas mitigadoras dessa escassez se tornarem muito elevados. Portanto, o modelo de cobrança proposto neste trabalho procura garantir que o agente econômico que está exaurindo o meio ambiente não possa ter capacidade de pagar por essa degradação, ajudando efetivamente a política de outorga do direito de uso da água na observância da capacidade de suporte do meio. / In Brazil, the Water Resources National Policy incorporates the water pricing as an economic tool for water resources management. Considering this definition, the water pricing must accomplish the following objectives: to promote the efficient use of the resource considering its shortage; to recognize the water as a good (commodity) with economic value, internalizing the environmental costs of externalities originated from the use of water resources; to reduce the conflicts of water use through an allocation system which balance the society priorities with the water demand management. The water pricing is included as a management tool in a policy whose primary objective is to \"ensure water availability for current and future generations with suitable quality standards according to its respective uses\". So besides the goals mentioned above, the water pricing must be implemented in a way to induce the user to behave towards the environmental sustainability. Based on these fundamentals, this research presents the conceptualization and application of a pricing model for water use that considers the principle of environmental efficiency evaluated by the adequate management of the water shortage. Following the environmental efficiency, the model also pursues the economic and financial efficiency of the water resource system. This predominance of the environment over the economy weakens arguments that the water use impacts would be compensated indefinitely by financial investments in infrastructure. To admit that economic development has this power is similar to mistakenly assume that the economic dimension is the limit for the environment, and not the opposite. This argument clarifies the problem of the majority of the water pricing methodologies, which define the value of water based on wastewater treatment costs and on hydraulic construction costs. Even if these pricing methods are very well defined in a way that they define prices for water diversion or wastewater discharges higher than prices for rational use, the price of water cannot be based on indicators whose sustainability may end in the short time, in accordance with the economic growth. The sustainability of the water resources as fundamental for the water pricing will be accomplished when the price charged for the water reflects the shortage of the resources, and not the cost for mitigation measures. So, the water-pricing model proposed in this research tries to guarantee that the economic agent who is degrading the environment will not be able to pay for the costs of this degradation.