Evening view of the junction of Rio Iguazú (right) with Río Paraná from Argentinian Bank, Brasil to right and Paraguay left (Ciudad del Este high rises in distant background), 2007
©EOP
Water transportation is not going to be a topic for discussion in the course, nor will wildlife conservation issues be emphasized, but they are both related to human water use. At the moment I am also preparing to lead a course on the Southern Cone of South America where the Paraná and its tributaries are important for transportation, for wildlife, and for water supply. The Paraná is navigable for small ocean going ships upstream as far as the Argentinian city of Corrientes, and its branches can be navigated further upstream into Brasil and Paraguay by shallower draft vessels. Landlocked Paraguay has long been dependent on the river for transportation access, and inland Argentinian cities including Corrientes and Rosario are also dependent on river transportation for access to world markets. More recently the commodity production boom in Brasil has greatly increased transportation demand as that country extends its ecumene into the interior.
The Rio de la Plata river system, including the Paraná its largest single stream, is one of the world's great river systems with a flow second only to the Amazon in the Americas.Its flow comes mainly from rainfall in the humid zones of subtropical and tropical southern Brasil, though it is not an exotic river for there is an excess of precipitation over evapo-transpiration in normal years along much of its length. Several huge hydroelectric projects on the Paraná provide much of the power used by Brasil, Argentina and Paraguay and have converted large segments of its upstream basin into slackwater lakes. As yet the Paraguay, a major tributary to the Paraná and navigable in some years into Brasil, has not been dammed.
A problem for navigation is the uneven flow across the year and from year to year. Hidrovia is a project to even out the flow of the Parana by manipulating water in the Pantanal, the immense marshland on the boundary between Brasil and Bolivia. While the project is apparently moribund at the moment, it is likely to be revived. The problem is the Pantanal is one of the world's great wetlands, and one of the largest still largely untouched by human activity. Known for the diversity and density of its wildlife, conservationists argue that it should be preserved in its current state.
In future postings I shall examine Hidrovia in greater detail and look at other aspects of water availability and use in South America.
