insurmountably costly to use. Such is the case in Tehran. As is happening in many megacities worldwide, metropolitan Tehran is experiencing rapid urban growth, with serious concerns being raised regarding the environmental sustainability of this development, and the potential detrimental impacts on the quality and quantity of groundwater resources.
The city of Tehran, with an existing population of over 7 million people, covers an area of approximately 730 km2 and lies within the Tehran basin on the semiarid plains to the south of the Alborz Mountains, with a varied terrain; from steep hilly areas in the north to plains in the south. The average slope of the area ranges from 1.3 to 5 percent. The mean annual precipitation is only 250 mm and occurs mainly during the winter and spring. No rivers of any size pass through the basin, but groundwater is contained in the extensive alluvial aquifer that underlies the basin.
What is needed is to move away from the technical-fix dominated, and largely supply-oriented management structure of water resource management. The focus has to be extended from blue water flow to incorporate also green water issues, and from water quantity to incorporate water quality as well.
An integrated approach is necessary for environmental management and water management of megacities like Tehran. Urban planning, as it relates to water, should encompass the integration of the physical land beyond the city limits, considering both the river basin where the city is located and the surrounding region affected by and interacting with the city. Planning should also incorporate a multisectorial framework. All sorts of interdependency linkages and implementation barriers need to be addressed in an overarching and integrated manner. The conventional setup of sectoral water management institutions is not able to cope with the present water problem facing the city of Tehran. The solutions to these problems require an integrated approach to water, land use, and ecosystems, addressing the role of water within the context of social and economic development and environmental sustainability.
Basically what is spoken of as a water problem in the city is not solely a water problem but a societal problem; the main task is to master the driving forces, to build up the balancing forces, and to develop competent governance systems. Megacities like Tehran are not able to cope with the growth of the suburbs, and in many cases development has gotten out of control. The unbalanced population growth and reliance on long distance water transfer are among the challenges that the city faces.
Problems that are facing water resources management in Tehran can be summarized as increase in demand and waste production due to population growth and socioeconomic development; decrease in availability of water per capita; high losses of urban water; and local depletion and pollution of surface and groundwater. Urban water management in this city will fail without a holistic and integrated view.