The Reconquista River Basin is located in the Province of Buenos Aires (Argentina). This area expands to the northwest of the Metropolitan Area of Buenos Aires (MABA). The waterhead of this basin is located in a predominantly agricultural and agro-industrial area. Towards the river's mouth, urban and industrial density increases, as well as its pollution levels. Most of the basin lacks sanitation infrastructure, and the main water supply are the underground aquifers and water tables nearer the surface, in some cases contaminated with fecal bacteria and industrial pollutants.

The purpose of this study is to propose policies that allow for equitable water allocation between competing urban activities in the Reconquista River Basin. I tried to find a relationship between current environmental problems and the underlying interaction of population in environment, in terms of different types of transitions and their stabilization. I identified critical areas in terms of water use and water quality. Based on this analysis, I defined sustainable levels of use of water resources, and proposed allocation between activities. Policies that might be applied to the river basin cover the areas of education and behavior patterns, economic activity, increasing the provision of sanitary services through water supply from surface waters, and expansion of sewer systems. Coordination between all the interested parties in the basin is essential for success in the implementation of these policies.

The work most closely related to the issues I address here is Marnie's study on Population Migration and Water Usage in Tucson, Arizona: Transitions in resource supply and resource management policies. Her analysis provides a deeper description of aquifer dynamics, and we both observe the lack of planning in urban growth and development within the constraints posed by the local environmental dynamics. Migration, as a response to the incentives for development, imposes the greater stress on the water resources in both studies. In Tucson, given that it is located in an arid region, water might be perceived as a limiting factor more than in Buenos Aires, where precipitation is more or less uniform along the year and amounts to around 1,000mm/year. Water is "always there", and this perception is enhanced when the source is not visible, as is the case of groundwater aquifers. Social (economic development) processes are much faster than the cycles of natural resources, and human communities tend to force the latter to match their own rhythm. The consequence is environmental deterioration, and since societies are sustained within environments, social deterioration cannot do anything but follow.

The common thread linking all the studies is this blindness alienating human activities from the environment from which they draw their resources, not only for economic purposes, but for cultural, spiritual and social purposes as well. Whether it is poverty, AIDS, street children, overpopulation, uncontrolled urbanization, agricultural mismanagement, environmental degradation or social inequities, all these factors have in common that they appear when human communities lack the ability to perceive themselves as part of a greater environmental system. Understanding how the dynamics of population and environment relate as an integral system is essential for generating healthy environments.

Tradition and culture are very locally based, and are therefore very important in providing an identity, a perspective from which communities can relate to their environment. This is closely connected to a sense of ownership that may also encourage a better caring and, consequently, a better management of the different resources that communities need for sustainability.

In the core of this alienation of man from its surroundings is the definition of progress as perpetual growth. This concept does not exist in environmental dynamics. While environments progress in cycles, human ambition of progress is linear. Until this gap is closed, stabilization of population growth, urbanization, toxicity and other related transitions is going to be very difficult to achieve.