BCN. The shortage of fresh water
Library of National Congress of Chile-BCN, January 2006, Chile.
Rivers, lakes, wetlands and streams are the main sources of fresh water. The population over time has been set up near them because it vital importance. One of the biggest problems facing humans today is the idea of water scarcity, and that one day this resource runs out, because water supplies are limited and pollution is a threat constant.
According dates released by the INFO Project at Johns Hopkins University, since 1940 global water withdrawals per year has grown on average between 2.5% and 3%, compared with an annual population growth from 1.5% to 2%. In the past decade water withdrawals in developing countries has been increasing at a rate of 4% to 8% per year.
As population grows, increase the number of countries facing water scarcity conditions. It is said that a country have water stress when annual water supply drops below 1,700 cubic meters per person. When he descends to levels 1,700 to 1,000 cubic meters per person, can be provided periodic shortage or limited water. When annual water supplies drop below 1,000 cubic meters per person, the country faces water shortage. Once a country is experiencing this situation, it can expect a chronic shortage, threatens food production, hinders economic development and damage ecosystems.
According INFO, there are 50 countries that already face water shortage, some of whom are Iraq, Angola, Ivory Coast, Egypt, Somalia, Madagascar, Jordan, Afghanistan, Tunisia and Kuwait. If the amount of people in the world continues to increase, it is estimated that we will pass from 6,000 million to 8,900 million by 2050, it is clear that more water is needed to feed it. The increased demand for fresh water worldwide is also due to increased technological development (companies dedicated to this area often have unique and independent supply of water), massive urbanization, and high living standards (a kilo of meat from a cow fed grain needs at least 15 cubic meters of water while a kilo of cereals needs only three cubic meters).
Global warming may even be targeted as a cause of shortages. Progressive drought and lack of rainfall in different parts of the world, especially Africa, are causing rivers to reduce their flow regime, that lakes and reservoirs levels decrease and will eventually ruin the soil for to crops. This is especially serious for people who see the rain its main source of fresh water. And, conversely, heavy rainfall in areas not prepared for it provoque floods and cause that water rain can not be exploited. To this we add that the increase in global temperature is causing the melting of glaciers and ice, which account the 70% of the world’s fresh water.
Another problem touches the progressive deterioration of freshwater quality and lack of investment funds to provide permanent drinking water sources, an issue that in the eyes of specialists has been largely neglected and whose magnitudes are not known in some countries. Where more affected is this factor in the agriculture sector, since 69% of water used today in the world is for her. The 23% of water is used by the industry and the remaining 8% goes to domestic use. The problem is that the chemicals used as fertilizers go into underground water, also called groundwater, these waters are of vital importance because they are a source of water for drinking and irrigation. However, it is easy to deplete or pollute because it renews very slowly. When water becomes contaminated groundwater can not be debugged by itself, as it tends to surface water because groundwater flows are slow. These groundwater are only a few feet of the ground, therefore, when on a farm the fertilizers are applied, they take little time to get to the source. The same is true in the case of garbage. The toxic liquid waste arising due to its decomposition, reaching the groundwater. Although it takes longer than the fertilizer, the damage is the same. Furthermore, these groundwaters suffer from a low refresh renovation. Strangely enough, the growth of urban areas affect freshwater supplies, not only by population growth. When it rains, the floors paved prevents water absorption to the groundwater. That liquid stagnates or accumulates in places unsuitable where, in the worst cases, can become contaminated. The paving is also a cause of flooding after heavy rainfalls, as in Santiago.
The water situation in Chile
According to the Water General Direction, the availability of water from the north of the country to the metropolitan area is less than 1,000 m3 per capita per year, which is considered low according to international standards. From Region VI to IX availability grows between 6,000 and 30,000 m3, which is considered to be loose, and from the Region X in the south is providing more than 100,000 m3. The initiative with the problem of freshwater scarcity will not be completed within a short time. As many experts say, is only to create awareness among citizens so that the resource can be kept clean so that they can use. It is advised to rationalize conserve water use in every area: domestic, agricultural (irrigation systems that do not require many resources) and industrial. Some countries are even treating waste water, for drinking again.
In the world there are various entities are addressing the issue of water.
The World Water Council (WWC): A discussion platform established in 1996 at the initiative of renowned water specialists in water issues and international organizations, organizes the most important event in the area: the World Water Forum. Its aim is to generate a dialogue that influences on public policy of water supply. The forums were held in Morocco (1997), Holland (2000), Japan (2003) and Mexico (2006).
UNESCO also has a program called International Hydrological Programme. Through it is intended that States have a better understanding of water issues in order to adapt their public policies.
Furthermore, the UN held every March 22 the World Water Day, as a body to disseminate, educate and raise public awareness of the care that we have with the water that use to live.
In Chile there are different rules and a number of bills that deal with agricultural irrigation, treatment of sewage, potable water use and, in general, pollution. To this we must add the Guide to Secondary Standards for Water Quality, published in December 2004 by the National Environment Commission. This guide contains proposed criteria, definitions, types of quality, values, parameters, methodologies and program management of monitoring of water resources, among others.