Transboundary Aquifers System Conservation, Protection and Sustainable Use in Mesoamerica


In 2004, in an ongoing program of action, Integrated Water Resources Management (IWRM), under the Department of Sustainable Development of the OAS (DSD/OAS), supported UNESCO’s global agenda of transboundary aquifers, as part of UNESCO-OAS ISARM/Americas Program. Each member of the OAS designated a National Coordinator (NC) to the program, nominated by the institution responsible for Underground Water Resources Management of his/her country.

The National Coordinators of Mesoamerica identified and preliminarily mapped 18 transboundary aquifers, with the profile of physical, economic, environmental and social factors that condition the aquifers and the national legal frameworks in which management currently falls. In this sense, the UNESCO-OAS ISARMA/America Program gives a resource of information which can complement and facilitate the activities of the proposal project.


The countries that make up the Mesoamerican isthmus face difficulties in resolving the equitable access to water for their populations, which if exceeded will mean the eminent enlargement of safe water supplies. This need to incorporate new water resources for human development is currently centered on underground water, the access to aquifers and the use of them. The emergency pressure on aquifers should not put the availability and sustainability of this natural resource at risk. Given the high political fragmentation in this region, with many countries involved in a relatively small territory, transboundary water (both surface and underground water) is particularly key because a joint coordination effort is required in order to have a better understanding, protection and promotion of use to ensure their sustainability, on a stage of development and overcoming poverty. This approach promotes mutual agreement between parties that is geared toward decision making in the regional and national frameworks.

The Mesoamerican situation, its latitudinal location, and the topographic variations of the land make for a unique environment in terms of water availability with an average of 27, 200 m3 habitant/year. Despite this abundance, the resource wealth is not distributed in an equal way in among the countries, nor within the respective countries, nor by its slopes, where the Atlantic Ocean shows overabundance of the resource while in the Pacific has high average deficits. Water scarcity is prevalent in countries like Mexico, El Salvador and Guatemala (see graph 1). While the Atlantic slope has 71% of the total water resource and has a low population density, the Pacific slope has the highest percentage of population (includes the capital cities of almost all Central American countries) but which has only 21% of water resources. The World Meteorological Organization cites that Central American countries have few actual problems of scarcity, using on average less than 10% of the water resources available. However, projections made for 2010, 2030, and 2050 indicate that, for example, by 2030 El Salvador will show initial levels of stress (13.2%) and for the year 2050 high levels of water stress (22.98%). Therefore, for the year 2050 countries like Guatemala and Costa Rica could also have scarcity problems. These future problems of water stress are already present in important areas of Pacific Isthmus slope, added to this problem the low demand, limited by the lack of access to water for a high percent of the population.

The Human Poverty Index for developing countries considers the average of number of people without access to potable water, children under five years old and underweight, and the percentage of people who do not live until 40 and the percentage of illiterate adults, as variables. In the case of Central America, this index for 2004 indicated a high index for El Salvador, Honduras, Nicaragua and Guatemala (CEPAL, Graph 2 attached). Additionally, these four countries are in the region which had the highest level of people who live on less than one dollar a day.

The document presented for Central America to the Fifth World Water Forum in Istanbul states: “Central America can de defined as a Transboundary Basin region, that is, in a space of a little more than 523,780 km2 there are 23 transboundary basins, which make up 41.49% of Central America. In this area, the rivers Usumacinta (Mexico-Guatemala), San Juan (Costa Rica- Nicaragua and Coco (Honduras-Nicaragua) are the longest.”

On the other hand, the countries of Mesoamerica have recognized in an initial survey, made in the framework UNESCO-OAS ISARM/America program, that it shares 18 transboundary Water Aquifers, of which 11 are located in strong water deficit, in the most dry and populated slope of the Pacific.

Overcoming these conditions are the projections of climate change made to the Central America region in CRR/SICA of 2006. It states that the possibility of a climate with a drier Pacific slope and more rain on the Caribbean slope of Costa Rica. These conditions worsen seasonal water stresses present in the region.

Proposal of Actions

Early in 2009 the Regional Water Resources Committee (CRRH) asked for the support of the OAS Department of Sustainable Development Department (DSD) to advance the ISARM/America Program in the region. The CRRH was knowledgeable of the success of the “Protection and Sustainable Use of Guarani Aquifer System Project in South America,” which was funded by GEF through the World Bank and executed by DSD/OAS. As such, they created a program with the following objectives: (i) further the scientific and technical knowledge of transboundary aquifers that need attention in Mesoamerica; (ii) define adequate management tools (iii) promote sustainable use and resolve issues of social and economic development; and (iv) advance the strengthening of the local management capacities, in the regulatory frameworks and national politics, in both a harmonic and cooperative way. The initiative was proposed in the meeting of Focal Water Points of Central America and Mexico at the OAS, which took place in Guatemala in February 2009. It was decided there that the project could be funded with money from the Australian Government, as the National Focal Points considered the development of the project idea to be of interest.

Mesoamerican countries understand the importance that underground water sustainable management means to their future development and seek to deepen in whole of this project. Other objectives of these countries include: improving their knowledge of underground water; gaining capacities and sustainable management tools for this resource; and identifying the history of these transboundary aquifers, to better understand their current or emerging uses.

Mexico participates in the project with substantial technical experience and capacity in aquifer management under extreme conditions. As such, this project could promote horizontal cooperation among countries of the Mesoamerican region.

The following are the main activities completed before the presentation of this project:

  • Meeting between the National Focal Points and the OAS to discuss the interest and national commitment with potential proposal. This occurred in Guatemala in February of 2009.
  • Inventory information linked with aquifers, especially on Mesoamerica’s borders. This was prepared by CRRH/SICA, in consultation with the PREVDA Programme framework.
  • Analysis of underground water resources in Mesoamerica, which was prepared by UICN-Mesoamerica.
  • Funding request to formulate a project proposal to GEF. This was prepared by the OAS/DSD, approved by the Finish Government, and will be executed in 2010 by CRRH/SICA.
  • A working formulation team has been created and documents have been made in the adequate format.
  • The final proposal formulation was prepared by CRRH, OAS/DSD and GEF implementation agency.
  • Presentation of proposal to GEF, OAS/DSD and Implementation Agency.
  • Initial workshop to formulate a project proposal is planned for May 4-7 2010 in Costa Rica. This project is supported by the Mesoamerica Cooperation Programme (Mexico-Central America), the OAS-DSD and UNESCO under the framework of ISARM America.
  • Secondary workshop to formulate a project proposal is planned for August 2010, in Mexico. This initiative is supported by Mesoamerica Cooperation Programme (Mexico-Central America), the OAS-DSD and UNESCO, under the framework of ISARM America.
  • Organization of American States- Department of Sustainable Development (OAS-DSD)
  • Central America Integration System (SICA)
  • Regional Water Resources Committee (CHHR)
  • National Water Commission (Conagua)
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November 13-19 2011. Medellin, Colombia. Seventh Inter-American Dialogue on Water Management (D7)


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