New paradigms in urban water management for conservation and sustainability

In order to achieve a sustainable degree of water resources usage, new paradigms in urbanized basins planning must be adopted. Worldwide urbanized areas total population has overcome in 2010, its rural counterpart. While urbanization can be a powerful driver of sustainable development, as the higher population density enables governments to more easily deliver essential infrastructure and services in urban areas at relatively low cost per capita, these benefits do not materialize automatically and inevitably. Water bodies are usually severely hit and impaired by poorly planned urbanization. Old water resources planning paradigms must be abandoned and new ones, which include the connection of 'green cities' and their infrastructure with new modes of drainage and landscape planning and improved consideration of receiving waters, ought to be adopted. These must not only be environmentally and ecologically sound, but also functionally and aesthetically attractive to the public. New eco-cities shall no longer rely on excessive water volumes withdrawn from often distant surface and groundwater sources, with a once-only use of the resource, and large water losses due to leaks and evapotran-spiration. Long-distance transfer of wastewater and high energy usage and emissions for its treatment should be avoided by distributed and decentralized integrated water/wastewater management. Effluent-domination shall no longer be a characteristic of urbanized river basins. The paper examines some of the paradigms that have been proposed for improving integrated water resources management in urban basins and illustrates some recent examples whether already implemented or still at the proposal stage.