Urban wastewater managment:Measuring the efficiency of Turkey's metropolitan municipality wastewater treatment services as a public good and services

Water is a life source with no substitute. Water is used for drinking, for basic vital needs, and for producing agricultural and economic goods. Concentrated population in city centers causes wastewater from domestic use to pose a threat to the lives of living creatures. Urban wastewater is managed and controlled publicly. The reasons for this are as follows: wastewater treatment facilities are natural monopolies; wastewater has external effects on health, ecosystem, and manufacturing; wastewater treatment has public or quasi-public good features; water and sanitation are human rights; and wastewater managment is at the center of economic and social development. Investment in wastewater treatment facilities and maintenance costs are financed by public resources and the income of the relevant institution. The purpose of this study is to examine the institutional and legal structure of urban wastewater management according to the Istanbul Water and Sewerage Administration (İSKİ) model - applied throughout Turkey from 1986 - and to make suggestions for the efficient provision of services by municipal administrations. The methodology of this study includes a theoretical review of the literature, graphic examination of up-to-date data and efficiency analysis of wastewater treatment facilities in metropolitan municipalities using data envelopment technique. In this context, good examples of management of wastewater treatment facilities financed by public resources are provided, with their components. The underlying aim is to view wastewater as a potential water and energy source rather than as a problem. Keywords: Urban wastewater managment, data envelopment analysis, public expenditures, Metropolitan Municipality