Towards the Modeling of Sustainability into Urban Planning: Using Indicators to Build Sustainable Cities

During the process of building the sustainable development paradigm in the last four decades, the incorporation and integration of the urban dimension has been gaining importance, while it has been acknowledged that the majority of the most serious environmental threats are exacerbated by the high density and activity of urban life and its consumption patterns. Thus, different methods, techniques and instruments for urban sustainable assessment that seek to figure out how cities can become more sustainable have emerged. Among which, indicators are increasingly used as they provide a solid foundation for decision making, at all levels, and contributes to the building of sustainable self-regulated systems in which development and environment can be integrated. The present paper builds on the background of the recent movement towards the usage of indicators by introducing a carefully chosen set for quantifying sustainability performance at the urban level and into the planning process. By moving indicators from the ex-post evaluation of cities’ problems to an ex-ante stage in which they can be operationalized as planning tools, this piece of work provides a contribution to traditional urban planning instruments and moves a step forward with regard to the construction of sustainability. In this framework indicators become key instruments in urban analysis, the design of policies, strategies, actions and programs for sustainable urban development. The paper starts by introducing the methodology and the urban sustainable indicators system for planning. This model then is tested and applied in a case study based on Mexico City's metabolism. Finally, the study provides a series of reflections on how successful strategies to enhance the long-term sustainability of cities can be developed by introducing sustainability indicators into the urban planning process.