Tehran, the capital city of Iran, has had many problems in the environmental field. Wastewater collection and treatment is one of most important of those. Tehran Sewerage Company has worked on the integrated wastewater management of Tehran by considering rapid population growth which results in increased water consumption and consequently more wastewater production. The wastewater project of Tehran began in 1959, but was stopped by the revolution in 1979. It was started again with financial support from the World Bank in 1990. This study conducted an environmental, social and financial assessment (short, medium and long term) of the Tehran Sewerage Project. Results showed that this project has moderate and temporary effects on environment and social communities. Furthermore, this paper proposes a management plan for mitigation measures (environmental monitoring and auditing). The combination of three solutions – governmental financial resources, public–private participation and the World Bank loan – as a function of three main factors – time, resources and quality – is discussed and investigated from an economic point of view. In this respect, supporting the private sector participation is considered as one of the critical factors for the success of the project.
environmental effects, fi nancial assessment, social effects, sewerage, Tehran Sewerage Company, wastewater
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