INTERAMERICAN WATER WEEK


Water in Latin America
Water was a scarce resource in the pre-colombian times and also valuable and fundamental for development, since the economy was basically agricultural. The cultures in this period developed necessary knowledge and technology in order to satisfy their needs and used their natural resources in an appropriate way and were concerned with water conservation. The Latin American people took into consideration three essential aspects of water usage: 
  • The organized participation of the community 
  • Use of technologies suitable for the area 
  • Management of different ecological environments 
The adopted economical development model affected the environment in a negative way later on. The industrialization process is one of the main causes of indiscriminate depletion of natural resources. The way of using the water has always been related to the dominant systems of production within the different development phases. What prevailled in most countries was an ecologically destructive pattern. 

O único planeta que tem água nos estados sólido liquido, gasoso e poluido.
We now live in a shortage of resources period with difficulties in expanding the economical basis and saturation of industrial production waste tips.

LATIN AMERICA AND CARIBBEAN CURRENT STATUS

The intensively growing use of water resources has been forcing the adoption of regulation measurements and alteration of the water courses, which causes changes in the ecossystems and microclimates, resulting in damages to plants, animals and habitats.
The increase in water contamination is one of the main characteristics of the water resources use in Latin America and Caribbean. There are few cities with treatment plants for domestic, agricultural and industrial sewage, including pesticides
Up to now, the plants, animals and human beings have been managing to survive by adapting themselves to the environmental changes, but if there is an increase in contamination levels, the ease of regeneration and adaptation will decrease, resulting in the extinction of species and of environments that were formerly life-giving. Therefore, a planning process in order to prevent and reduce such a possibility is made urgent.

WATER DEMAND AND RATIONAL USE
There has been an increase in the demand for natural resources in the last decades, and water is the most sought-after and at the same time the most affected by the intensified use.
In Latin America the most intense uses are in irrigation, eletric energy generation and human consumption.

WORLDWIDE WATER USE


USE 
PERCENTAGE
Agriculture 
69%
Industry 
23%
Domestic 
8%

Many irrigation systems utilize the product in an excessive manner and therefore contribute to the degradation of high quality land due to salinization and flooding. On the other hand, the uncontrolled urban expansion and indiscriminate water captation for urban consumption have, in many cases, been affecting the agricultural production and important forest areas.
The amount of subterranean water that has been used for human consumption and irrigation is severely affecting its availability for future use. The exploration of subterranean waters should forecast the development of activities that assure the recharge of the aquifers.
The main source of superficial water contamination is the direct dumping of domestic sewage, generating a higher potential health hazzard to the population because of its presence in highly populated areas. The contamination of subterrranean waters is due mainly to the infiltration of excrements from pits and sewage network with defective maintenance, absence of sanitaion coverage, infiltration of toxic substances and industrial deposits and garbage dump spillways. In this last case, the preoccupation is even greater because 50% of urban and rural population capture water from subterranean sources for irrigation and consumption.
The economic activities that most contribute to contamination are:
 

INDUSTRY
 
 Through chemical and biological residue from industrial effluents. The highest pollunting industries are: 
  • Paper and celulose 
  • Petrol processing - Metalurgics 
  • Food 
  • Textiles 
PETROL AND MINING The contamination from mining is high in Latin American countries: 
  • Heavy metals 
  • Acids and solid particles in suspension 
  • Hidrocarbons close to the extraction areas and from oil pipe leaks and ships 
AGRICULTURE Agriculture contaminates water through: 
  • Uncontrolled infiltration, precipitation and drainage 
  • Fertilizers and pesticides
  • Irrigation methods that use water in an uncontrolled manner 

CONSEQUENCE ON PUBLIC HEALTH

Water contamination, caused by either industrial or domestic refuse, results in serious consequences to the quality of life and health of the population. In many Latin American countries, the lack of concern over water use and the weak drinking water service (unsufficient amount, bad quality, shortages, reduced coverage, high cost, precarious maintenance and operations) is added to the contamination problem.
Among the many diseases that are spread because of water contamination or lack of it and inadequate sewage systems are, among others:
 

The industrial effluents are much more dangerous than the domestic ones because they have high concentrations of organic matter and toxic substances. On the other hand many producs for domestic use have hazzardous chemical components that are dumped into the sewage or rivers and contribute to contamination.
When the organic amount of the dumpings gets higher than the water`s capaciy of self purification, the oxygen runs out, causing the death of fish and water plants.
Contaminated water used for irrigation and domestic vegetable growing not only harms the soil but contaminates vegetables and threats human health.
The toxic substances dumped into the water without previous treatment may harm fish and other animals that drink out of that water. These hazzardous residues may also accumulate on the tissues and cause serious problems to the health of the population such as cancer, heart and lung disease.
Contamination and waste of such precious asset result in higher costs in handling and storing it. Besides, it puts the water resources as a whole in jeaopardy, affecting the behavior of the watersheds.

OTHER PAGES ON WATER IN LATIN AMERICA

Importance of Water Basins
Issues to be Promoted
Administration and Management of Water Basins