Scarcity of water in the world, virtually, has two sources: the quality and the quantity made available for populations. In the area covered by this study, the selected municipalities from the river basins 3 e 4 of the Paranapanema River and from the basin of the Pirapó River, availability is always greater than the demand and the environmental problems are more often linked to the quality than to the quantity of water. To check the socioeconomic aspects and the daily practices involving water resources and environmental problems we selected a representative sample of families from 10 studied municipalities. The main conclusions point to the existence of key municipalities, regarded as foci of pollution, i. e., the municipalities do not contribute in equal measure to the pollution of rivers from their regions and some stand out in economic activities and inherited cultural practices. However, respondents did not always relate the environmental impacts with their routine and productive activities. Thus, although the new legal environment imposes new practices, there are still cultural heritages, which require more incisive and continuous public interventions.
A comparative study of available water in the major river basins of the world