by Mariano Franco

1 May, 2008

from Lepanoptique Website


The Guarani aquifer - a vast subterranean aquifer located in Southeastern South America - has recently become a contested site for resource management.


Lying beneath four countries and holding the possibility to sustain humanity’s basic need for potable water for generations to come, the delineation between national, regional and international jurisdiction, profit and sustainability, remain worryingly unclear and uncertain.


Local authorities, together with the international community, are facing a collective action problem.



Nevena, Water Drop, 2006




A vast water reserve for a thirsty world


The Guarani aquifer, named after the Guarani first nation, is a large drinkable water reserve with a 1.2 million sq. km. extension spanning across four countries:

  • Brazil (850,000 sq km)

  • Argentina (225,000 sq km)

  • Paraguay (70,000 sq km)

  • Uruguay (25,000 sq km)

In spite of its size (it would represent, for example, about 77% of the Quebec’s territory) the aquifer is invisible to the naked eye since it is subterranean. In fact, at issue is an old geological structure; an extremely big rock soaked in water.


This aquifer suggests itself as a very important strategic resource in light of global concerns regarding drinkable water.


Considering that only 3% of the world’s water is potable, and that a mere 21% of it is easily extractable (as the rest is frozen in both poles, glaciers, and on mountains peaks), humanity is shifting its focus towards the sustainable exploitation of alternative resources, specifically subterranean water reserves.


Though surface-level drinkable water is easily obtained, it represents only 1% of total potable water and is also mostly contaminated.


At present, more than 40% of the global population (3,600 million) does not have regular access to safe sources of potable water, and this number is expected to rise as climate change, pollution and population growth put increased strain on water resources. The scarcity of this resource takes its highest toll on the most vulnerable segment of society: 4,000 children die daily due to dehydration, diarrhea, and other illnesses related to contaminated water.1


As a water resource, the Guarani aquifer has enormous potential. Its volume reaches about 40,000 cubic km (Km3), with each cubic kilometer containing one billion liters of water, or enough to supply about 28 million homes per year in an average American city.


Though only 40 to 80 cu km could be exploited from the aquifer, it is still quite a considerable amount.2


It is also worth noting that the aquifer is a renewable water source, since over 166 yearly cu. km are obtained from rain that feeds the resource through certain water areas located mostly in Argentina, as well as from soil humidity.





Many protectors, one legacy


There is no doubt that the Guarani Aquifer is a precious resource that must be protected for the benefit of future generations.


One of the major threats it faces is linked to the aquifer’s surface, which is predominantly used for farming and live stock. Irresponsible waste management, fertilizers, and other agrochemical products are very likely to filter through the inner rivers and transitional water deposits, contaminating the reservoir’s core.


Climate change could also affect the required humidity level by reducing the moisture on the surface and complicating the water’s circulation from the outside to the inside of the aquifer.


Another less evident but equally important hazard to consider is irresponsible water extraction, which has two lethal consequences:

  1. an increase in the salt level

  2. a general lack of pressure

With regard to the first, salted water only currently represents 10% of the water reserve but negligent extraction could negatively affect this delicate proportion, rendering the water undrinkable.


Regarding the second, the existing pressure grade eases water pumping to the surface, but random extraction could render the extraction process impossible in the near future - or at least make it much more expensive than it currently is - as low water levels in secondary pools negatively affect the pressure of the whole aquifer.


Brazil, Argentina, Paraguay and Uruguay (founding members of Mercosur, the common South American market) understand the magnitude of the situation and have decided to take action. In 2004, these four countries declared full sovereignty over the aquifer and assumed shared responsibilities in order to preserve it.


These responsibilities include:

  • supervision over rain water renewal

  • pumping control

  • measures against pollution

It seems, however, that these measures do not extend past good intentions. Irresponsible exploitation continues to this day, as perforations are thought to allow contaminants into the aquifer. There is also evidence that in certain Brazilian areas more pressure than ever before is needed to extract potable water.


Brazil already has 300 perforation pumps, Paraguay 200, Uruguay 135 and Argentina only 6.


The distressing side of this story is that in these countries potable water coverage only reaches on average 75% of the total population, as the remaining 25% is dealing with alternative sources that could be unsafe.


If properly managed, the Guarani Aquifer, then, could become an excellent regional resource that benefits far more people than at present.





The S.A.G. Project


In May 2003 the World Bank (WB) met with the Mercosur countries in Uruguay in order to start up the “Sistema Aquifero Guarani - Guarani Aquifer System or SAG” project, a $26.7 million plan for the aquifer, funded jointly by the World Bank - WB (50% of total investment) and the four Mercosur countries (45%).


The remaining part of the project was financed by the Dutch and German governments, together with the International Atomic Energy Agency and the Organization of American States.


The WB’s rationale for intervening in the Guarani aquifer was chosen over two other alternatives: do nothing, or carry the project on an exclusively national basis in one or two countries. Whereas the first one was rejected due to initial signs of stress on the resource, the second alternative was rejected on the basis that the regional nature of the aquifer naturally implies that its continued degradation in one country will impact on all the other countries. 3


The S.A.G. project is still in an initial phase and, for now, consists of gathering information in order to determine the aquifer’s potential and securing its protection from the aforementioned hazards.


However, the idea behind the WB’s initial approach is to determine what would be the most efficient way to utilize the aquifer. In terms of efficiency, extractions from the aquifer do not yield pure water alone; they also contain stone and sand.


Therefore a more technologically advanced decantation process would help obtain a better quality and quantity of water. And examining the outflow and inflow zones would help to locate the best extraction areas, not to mention that better - and thus more expensive - pumping procedures could avoid introducing contaminants into the aquifer.


There are concerns that this initial phase of the SAG project could lead to a second phase involving the exploitation of the aquifer by multinational companies like,

...the principal international players within the water 'market.'


This suspicion is based on the pattern of WB-supported private investment previously experienced throughout Latin America.4


There are therefore valid concerns that in the name of efficiency and conservation, the administration of the aquifer would in fact transform it into a for-profit private business under the rationale that the aquifer is being squandered by local governments that cannot ensure its protection.


Concerns about the privatization of water were reflected in the words of Stefano Pagiola, Senior Environmental Economist in the World Bank’s Policy and Economics Team.


In the World Water Forum 2006 bulletin he explained that the concept of payment for environmental services is based,

“on two principles: users must pay for the environmental services they enjoy, and suppliers must be compensated for delivering them. It is a win-win situation insofar as it is based on common interests, and identified efficiency and sustainability as its main benefits”.5




A dangerous dilemma


When it comes to the administration of public resources, Mercosur’s countries have a negative track record, due in large part to a decades-long legacy of political instability and corruption.


In the case of the Guarani, no other important political step has been taken other than reaffirming their shared sovereignty over the aquifer. Yet, exploitation happens at the surface level where jurisdiction of the aquifer is not shared and countries individually affect the water resource.


Furthermore, budgets from these countries are either very tight or they do not reflect any serious intention aimed at exploring better drilling zones to protect the aquifer.


The WB’s monetary support, though appreciated, could be aimed to bridge the gap between private multinational investors and the aquifer resources. Even with an increase in the efficiency of the aquifer’s management, if potable water is to be obtained by for-profit organizations, it could very easily be turned into a commodity and its access more restricted than before.


It seems that we either,

  • risk the survival of the aquifer in the hands of countries with high corruption levels

  • or we let private companies take over this vital resource, possibly leaving those most in need out of the equation

Equilibrium between these two alternatives needs to be attained by letting the Mercosur countries administer the Guarani aquifer themselves, since their responsibility and legal rights over the resource are inalienable.


The international community should participate not by promoting privatization, but rather by helping these countries control their resource and create legal standards to manage exploitation and make potable water more accessible to all. The preservation of the Guarani aquifer is vital for humanity, yet it is a treasure that risks slipping through our fingers if we are not careful.


It is a treasure that must be protected yet shared at the same time, not just for the benefit of Brazil, Argentina, Paraguay, and Uruguay, but for the benefit of the entire world and the generations to come.






1. Information obtained from world water forum site as of 03/08 (

2. The average potable water usage in US is 350 Lt per home (source world water forum site as of 03/08 -

3. Information based on the report No. 23490 - LAC from the WB (May 17th 2002) “PROJECT APPRAISAL DOCUMENT”.

4. In fact in Argentina the water supply is owned by Suez through a domestic company named Aguas Argentinas. There was also clear intention of privatizing this resource in Uruguay. In Mexico similar arguments like the ones exposed by the WB were used to privatize the supply, which is ran by Vivendi.









Water Is The Next Oil

-   Beautiful Paraguay   -

March 22, 2011

from ArticlesOfInterest Website



"The Guaraní Aquifer... is one of the world's largest aquifer systems... It is said that this vast underground reservoir could supply fresh drinking water to the world for 200 years."


"US President George W. Bush allegedly has recently purchased a 98,842 acre farm in Chaco, Paraguay atop the aquifer. The Reverend Moon has also purchased 1,482,600 acres in Chaco, Paraguay."





The Guaraní Aquifer, located beneath the surface of Argentina, Brazil, Paraguay and Uruguay, is one of the world's largest aquifer systems and is an important source of fresh water.


Named after the Guaraní tribe, it covers 1,200,000 km², with a volume of about 40,000 km³, a thickness of between 50 m and 800 m and a maximum depth of about 1,800 m.

It is estimated to contain about 37,000 km³ of water (arguably the largest single body of groundwater in the world, although the overall volume of the constituent parts of the Great Artesian Basin is much larger), with a total recharge rate of about 166 km³/year from precipitation.


It is said that this vast underground reservoir could supply fresh drinking water to the world for 200 years.


Due to an expected shortage of fresh water on a global scale, which environmentalists suggest will become critical in under 20 years, this important natural resource is rapidly becoming politicized, and the control of the resource becomes ever more controversial.