The GEF Project on the Guarani Aquifer by qvs59240


									             Web-based information for integrated water resources
                    management of a multi-national aquifer:
         The Global Environment Facility Project on the Guaraní Aquifer

Eduardo Usunoff
Instituto de Hidrología de Llanuras
C.C. 44
(7300) Azul – Prov. Buenos Aires – Argentina
Phone/Fax: (54) (2281) 432-666

Introductory remarks

Given the global scarcity of water resources readily available, the Guaraní Aquifer
represents one of the world’ largest freshwater underground reservoirs. Shared by four
countries (Argentina, Brazil, Uruguay, and Paraguay) its known extent is of about
1.200.000 km2 (Figure 1), of which 70% are in Brazil, 19% in Argentina, 6% in
Paraguay, and 5% in Uruguay.

During the last 20 years, the amount of water pumped from the aquifer has been
increased steadily in response to demands from various sources (direct water supply,
industrial settlements, tourism-related needs, agricultural activities), which does raise
concerns on the proper (equitable) current use of the water and the sustainability of the
system in the context of integrated water resources management.

It is important to mention that more than 15.000.000 people live in the area, that the
largest South-American industrial cluster is nearby (San Pablo, Brazil), and that the best
trained technical resources of the four countries are in the region or around it.

The aquifer is in Permian-Cretacic sandstones, covered on at least 90% of its extent by
Jurasic-Cretacic basalts of varying degrees of fracturing/fissuring. Such sandstones
range in thickness from few meters to more than 800 meters (in Río Grande Do Sul,
Brazil). It is basically a confined aquifer, and its main source of recharge is infiltrating
rainfall in those places where the basaltic cover is not present. The groundwater flow is
from the North-East to the South-West, with waters which incorporate solutes along the
flow direction. The average salinity in the recharge area is about 50 mg/l, and can be as
much as 500 mg/l on the South-Western region. The general flow direction matches an
increase in groundwater temperatures, from 22 to up to 60 ºC, which has been mostly
attributed to the effect of the normal geothermal gradient.

Because of its extent, importance, and transnational setting, the Guaraní Aquifer has
been the subject of numerous hydrological studies (a very good summary can be found
in Campos, 2000), whose conclusions/findings can hardly be integrated due to the
varying degree of detail and the scale incidentally used. Several attempts were made to
come up with a unique, justified conceptual model of the aquifer, although such trials
were not as successful as expected because it soon became evident that basic
information was either unavailable or lacking. The shortcomings and limitations posed
by the lack of reliable information and/or its uneven geographical distribution were
assessed through groundwater modeling of a large portion of the aquifer (Figure 2,
          80°                           60°                                          40°
 10°                                                                                        10°

 10°                                          Mato Grosso                                   10°


                                                                             Minas Gerais
                                                   Mato Grosso
                                                   do Sul
                                                             Sao Paulo


                                                      MI     Sta. Catarina
                                                      Rio Grande
                                                      do Sul
 30°                                                                                        30°

                                                      500 km

   100°                 80°                     60°                            40°

Figure 1. Location of the Guaraní Aquifer in South America.

Vives et al., 2000), although such a exploratory tool helped define the future steps to
gain a much refined insight on the aquifer behavior.








-3600000                metros
           0      200000     400000   600000

       -1000000   -800000   -600000   -400000   -200000     0   200000   400000    600000   800000   1000000

Figure 2. 2-D fine-elements grid of the modeled area (after Vives et al., 2000).

Counting on technical and financial support provided by UNESCO, the IHP
(International Hydrological Program) National Committees of Argentina, Brazil,
Paraguay, and Uruguay prepared a project to unravel the hydrogeological potential of
the Guaraní Aquifer and submitted it to the World Bank in 1994 (details of the baseline
information used can be inspected in Indeed,
it took a long time and countless efforts to come up with the four national
hydrogeological maps, which were soon after included in a larger and much needed map
showing and explaining the hydrogeological features of the whole South America
(UNESCO/CPRM/DNMP, 1996). Such a map and the explanations can be downloaded

More recently, the four countries in the region decided to take on effective actions on
the subject and, along with Universities and NGOs, agreed on launching a project aimed
at the preservation and sustainable management of the Guaraní Aquifer. Because of its
transnational nature, such a task is currently in charge of the Global Environment
Facility (GEF). Born in 1991 as an experimental task group, the GEF mission and
structure emerged clearly after the 1992 Earth Summit held in Río de Janeiro, Brazil
(additional data can be found in The GEF has already assigned
U$A 350.000 (granted by the World Bank) to the project formulation, and expects to
receive future investments in the order of U$A 25.000.000 for carrying it out.
The early stages of the GEF project and other related information is already in Internet
(, and this presentation aims at putting up some ideas
that will greatly enhance its scope as related to the objectives laid out by the GEF.

Integrated water resources management and sustainability

In order to understand what is at stake, a brief definition of integrated water resources
management (IWRM) is in order. García (1998) considered that it involves projects and
actions aimed at increasing water conservation and water use efficiency. To achieve
such objectives, water managers should bear in mind that: (1) water resources are to be
used in a complementary way, (2) competing uses, in quality and quantity, lead to
conflicts which are to be minimized, (3) demand-oriented management is as important
as supply-oriented management, (4) clear and fear policies and regulations must be
available, as well as (5) well-trained human resources.

Although it is not explicitly mentioned in the paragraph above, sustainability is at the
heart of the IWRM. As related to water resources, there is no commonly accepted
definition of sustainability. However, it seems that current trends coincide with the
conceptual approach proposed by ASCE (1998, p. 44): “Sustainable water resource
systems are those designed and managed to fully contribute to the objectives of society,
now and in the future, while maintaining their ecological, environmental, and
hydrological integrity”. While it becomes increasingly difficult to estimate what future
needs or demands will be, it seems evident that whatever is done today to meet current
needs, society should not allow renewable water systems to be degraded. In doing so,
even though it may be impossible to know what new objectives future generations will
want to try to achieve, the initial assumption is that their objectives will be the same as
those of the current generation.

An approach to the desirable Web-based information

Given the extent of the aquifer, the current and potential uses of the water, the existing
laws and international treaties, and even the cultural and economical differences among
the four countries, it can be easily concluded that, while a Web page is a powerful tool
for most purposes, its features and contents have to be designed very carefully.

Such a hypothetical Web page should:

   1) be understandable for anyone accessing it. That implies using plain written
      Spanish and Portuguese, devoid of many technical terms. The specialists, those
      who already have the ability to handle the technical jargon, should be able to
      read/download the technical reports or data available.
   2) display information, whenever possible, in graphical form.
   3) be the host of all hydrological-related information. Currently, no one is sure of
      what is known and what remains uncertain about the Guaraní Aquifer. Although
      several technical reports have been issued, there is a wealth of raw
      (unprocessed) data that should be put to a good use. That would substantially
      reduce the cost of future investigations.
   4) keep updated records of on-going studies, new proposals of water use, and active
      policies regarding integrated water resources management. Such an updating
      must be supervised by a group of technicians guided by the Web page manager.
   5) allow feedback from stakeholders. Experience has shown that their direct
      involvement leads to better solutions, particularly in conflicting situations
      (competitive uses).
   6) offer links to federal or state laws/regulations libraries. Inasmuch as laws are
      lengthy texts, a search engine (based on selectable keywords) may be useful.
   7) reserve a special place for NGOs.
   8) Count on an on-line webmaster.

Three examples will are offered below, showing how effective a Web page can be in
solving real-world problems. Although the actual Web page consultation is fictitious,
those cases are based on actual initiatives.

Groundwater demand from tourism: An international investment company detected a
well-defined demand, which implies building a health resort near San Pablo City
(Brazil), making use of deep, thermal waters from the Guaraní Aquifer. If the Guaraní
Aquifer Web page fulfills the requirements mentioned above, it will be a matter of few
hours to retrieve information on:

   • Places nearby San Pablo where the resort can be built (after displaying a general
     location map, zooming-in capabilities would be desirable). Links to regional real
     estate developers would help find out details on land use/availability and costs.
   • Quality and quantity characteristics of the deep, heat waters.
   • Links to libraries of various categories dealing with the entire procedure for
     building a resort such the one proposed (construction norms, commercial rules,
     groundwater use and environmental protection laws, etc.).
   • E-mail addresses (regional tourism agencies, technical agencies/groups, official
     development agencies, etc.).
   • Ways to retrieve the opinion/views of local stakeholders, after filling up a form
     containing a brief description of the project (infrastructure, job opportunities, use
     of water, fate of wastewater, etc.).

Groundwater supply: Groundwater pumping has been used for years to supply the city
of Mercedes (Corrientes Province, Argentina). Those wells tap a rather thin unconfined
aquifer, which is currently overexploited and showing evident signs of quality
degradation. Decision has been made to drill deeper wells (no source of surface water is
close to Mercedes), so that waters from the Guaraní Aquifer would potentially supply
the city. Before starting off a drilling campaign, a session of Web page consultation
would be extremely useful for:

   • Finding out the quantitative and qualitative characteristics of the Guaraní
     Aquifer in the region.
   • Retrieving the hydrogeological/constructional features of wells nearby
     (lithological profiles, casing diagrams, specific discharges, transmissivities,
     storage coefficients, etc.).
   • Being aware that, by virtue of the Ramsar Treaty, since 1995 Argentina has
     assumed the preservation of the Iberá wetlands (fed up by the Guaraní Aquifer
     in that region). Therefore, any groundwater pumping is allowed as long as the
     wetlands recharge is not affected.
   • Getting in touch with researchers/professionals who may model the situation to
     assess the eventual impact of groundwater pumping on the wetlands
     hydrological regime.

Hydrogeochemical research: Water samples from the Guaraní Aquifer along the eastern
portion of Uruguay have shown high concentrations of fluoride. Its origin is not clear,
although some studies postulated that it may be the result of waters from different
aquifer horizons which get mixed through preferential pathways. A graduate student,
looking for a thesis topic, decides to carry on a hydrogeochemical study. A good
starting point would be to glance through the Guaraní Aquifer Web page in order to:

   • Inspect the chemical database.
   • Zoom-in on regional geological structures.
   • Get details on sampling wells (drilled lithology, cased and screened depths,
     discharge, etc.).
   • Find out who else may be working on the subject (links with universities).
   • Explore the research grants available.
   • Deliver a brief summary of the proposed research project.

The hypothetical examples above offer just a glimpse of a much broader spectrum of
capabilities of a well designed and managed Guaraní Aquifer web page. The ever
growing Internet hookups in Latin America (Fernández-Jáuregui, 1999) and the
remarkable advances in communication technologies (Anderson, 1999) may constitute
excellent tools for the challenge of achieving the sustainable management of the
Guaraní Aquifer.


Those living in the region know that, aside from financial support, the building of an
efficient Guaraní Aquifer Web page entails a high sense of openness, generosity, and
integration at all levels. It may take a while for it to take place, and some actions can be
suggested to catalyze the process:

   • Nowadays, the MERCOSUR (the South American equivalent of the NAFTA) is
     dealing almost exclusively with economical matters. It would be desirable that
     the water resources and environmental national authorities induce the inclusion
     of the Guaraní Aquifer management in the official agenda of the MERCOSUR.
   • Although bilateral and multilateral treaties involving the countries in the region
     are in effect, most of them are not backed up by common laws or rules of
     multilateral validity. Therefore, promoting legislative actions to develop legal
     instruments for the “water resources joint ownership” concept should be of
     primary concern.
   • Data standarization and quality control, as well as the inclusion of social and
     economical issues (holistic, multidimensional, and multi-objective approach),
     are in order. Experience has shown that handling many variables of different
     type and source with multiple objectives can become a cumbersome task. In that
     sense, an expert system should be available. Incidentally, the LACHYCIS
     information system (Fernández-Jáuregui, 1999) does represent an advanced
     effort bound to be easily enriched in the near future given its potential (details on
     LACHYCIS can be accessed at
   • There is no doubt that an acceptable knowledge of the Guaraní Aquifer behavior
     is a pre-condition to any initiative. Substantial resources should then be assigned
     to the completion of the aquifer conceptual model, taking as a baseline the
     findings of Vives et al. (2000). Such a task should include as many
     hydrogeologists as possible (either as a operational human resources or data-
     providers), in which can be conceived as a multi-national research team, and the
     results be disseminated “effectively” among regional water decision-makers
     (who, as pointed out by Fernández-Jáuregui (1999), do favor friendly
     approaches due to their lack of expertise in technical grounds).
   • The on-going UNESCO’ TAM Program (Transboundary Aquifer Resources
     Management) is tailored in such a way that the Guaraní Aquifer may well be
     included as a pilot case.
   • Special attention should be given to the way that stakeholders may benefit from
     the Guaraní Aquifer Web page. They should be convinced that the Internet
     resources are most effective in achieving common objectives. Their participation
     is essential in retrieving their demands and helping shape the outcomes of water
     management and policy actions. Then, counting on e-conferences and video
     conferences capabilities would be a must.


Anderson, F. 1999. The challenge of leveraging the Internet for a sustainable water
management agenda: Enabling global cooperation and local initiatives. Water
International, Volume 24, Number 2, pp. 126-139.

ASCE. 1998. Sustainability Criteria for Water Resources Systems. American Society of
Civil Engineers, UNESCO/PHI IV Project M-4.3, Reston, Virginia, 253 p.

Campos, H. 2000. Mapa hidrogeológico del Acuífero Guaraní. Proceedings of the 1st.
Joint World Congress on Groundwater, Fortaleza, Brasil, 15 p. (in CD format).

Fernández-Jáuregui, C. 1999. Hydrology and water resources on the Web in Latin
America and the Caribbean. Water International, Volume 24, Number 2, pp. 157-159.

García, L. 1988. Strategy for integrated water resources management. Technical Study
Nº ENV-125, Inter-American Development Bank, Washington, D.C., 36 p.

UNESCO/CPRM/DNMP. 1996. Mapa hidrogeológico de América del Sur, Escala
1:5.000.000, Texto explicativo, Brasil, 210 p., 2 maps.

Vives, L., Campos, H., Candela, L., and Guarracino, L. 2000. Premodelo de flujo del
Acuífero Guaraní. Proceedings of the 1st. Joint World Congress on Groundwater,
Fortaleza, Brasil, 19 p. (in CD format).

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