Sustainability Indicators for Assessment of Urban Water Systems: The need for a common ground

The cities are facing a growing pressure for sustainable water services in a scenario where water is becoming increasingly scarcer. Most urban water systems (UWS) were developed under criteria guided by hygiene and efficient performance goals that are not necessarily encompassed with sustainability principles. Are the UWS sustainable? Answering this question is strategic to plan viable cities in the future. But measuring sustainability is a challenge itself. Indicators are one tool in the attempt of assessing sustainability. In this paper, 13 different set of indicators have been analyzed. Many similarities where found but also many underlying conceptual differences. This comparison raises five main tensions when sustainability indicators (SI) for UWS are designed. 1) What is the system under analysis? Or, in other words, what is UWS comprised by? 2) What is considered as “sustainability ” of UWS? 3) Should the emphasis be on current water problems or on thinking about the future viability of the city? 4) Should the emphasis of SI for UWS be on internal performance or external effects? 5) How should the diverse stakeholders ’ views and interest be taken into account? These are key questions with not easy answers. Multiple visions of sustainable development need to be contrasted in order to come up with a set of indicators in both technically sound and politically relevant terms. It is a call for integration of methods from diverse disciplines that allow a dialogue, not only among parties involved but also among disciplines. In that sense, an initial proposal is made in this work