There is no aggregate shortage of water in Latin America. The Amazon’s output into the Atlantic Ocean is about 150,000 cubic metres per second and a whole host of smaller rivers—the Magdalena, Orinoco, San Francisco, Uruguay, and Usumacinta rivers, to name but a few—all carry more than 1,000m3/sec of water into the ocean at their outlets. In contrast, Buenos Aires, Mexico City, and São Paulo, the three largest cities in Latin America, consume around 50 to 80m3/second, clearly a very small amount when compared to total available regional water resources (Anton 1993: 163). However, Mexico City is situated in an extremely water-scarce area, and other cities such as São Paulo, Brasilia, Guatemala City, Quito, and Bogota are located far from plentiful sources of water. Elsewhere, though, large cities and abundant water sources are in close proximity, yet large parts of their population still suffer from a lack of clean, cheap, and convenient water, a situation of scarcity in the midst of abundance. This chapter will examine the problems faced by the urban poor in Latin America in accessing potable water, and will examine the problems associated with its delivery. Although it contains some very arid areas such as the Atacama Desert, Latin America is a humid region. Until recently, water was regarded as an abundant resource, and justifiably so: Latin America’s annual precipitation is 60% above the world average and the average annual run-off of 370,000m3 is 30% of the world total (Biswas 1979: 16). A glance at water consumption levels in Latin American cities indicates no aggregate shortage of water. Table 3.1 suggests that average daily water consumption in Latin America’s big cities is comparable with that of cities in the developed world, and significantly higher than is the case in African and some Asian cities. Given that the very minimum amount of water deemed necessary to sustain life has been estimated at 5 litres per capita per day (LCD) (World Bank 1976), and that under most circumstances 30/40 LCD is deemed sufficient for a reasonable level of personal and community health (Kirke and Arthur 1987: 125), even the city with the lowest consumption level would appear to have a plentiful supply of water.
Evaluation of ecological quality in peri-urban rivers in Mexico City: a proposal for identifying and validating reference sites using benthic macroinvertebrates as indicators
