Conclusions

Central America appears on the surface to be a water-abundant region. However, as described elsewhere (e.g. Shah, Chapter 2, this volume), population and water supply do not overlap. Further, supply is not consistent throughout the year, and there are often problems with quality due to sedimentation and pollution. These issues, combined with growing populations, have already brought out general challenges for supplying water for agricultural, domestic and industrial purposes throughout the region.

However, unlike the other regions covered in this book, there is currently little groundwater used in agriculture in any of Central America's countries.

Table 6.12. Costa Rica: concessions granted by the Water Department of the Environmental Ministry by type of source and use, February 2004. (From Water Department, Environmental Ministry of Costa Rica.)

Type of use

Surface water

Wells (underground)

Total

Agricultural/fishing

28,793.6

162.3

28,955.9

Agro-industrial

6,608.9

1,693.8

8302.7

Irrigation

121,118.0

2,495.5

123,613.5

Human consumption

3,958.8

1,556.5

5,515.2

Commercial

83

98.2

181.1

Industry

4,218.9

1 ,956

6,175

Hydraulic energy

722,965.6

722,965.6

Tourism

2,974.3

568.2

3,542.5

Total

890,721.1

8,530.5

899,251.5

Figures collected for this chapter show a total of less than 50,000 ha under groundwater irrigation, with most of that figure in Guatamala. At least three factors help to explain this outcome. First, there is relatively little irrigation in the region in general. Second, when irrigation does exist it is (in rural areas) usually supplied through relatively abundant surface water, which is generally of lower extraction cost than groundwater. Third, the main aquifers in Central America are generally located under metropolitan areas or, in other words, metropolitan areas have tended to grow over the main aquifers.

To date, the main use of groundwater in Central America is for household consumption, followed by industry and tourism activity. Still, the experience of Central America, both in terms of its overall groundwater situation and with reference to its urban use, highlights many of the stories, issues and challenges brought up elsewhere in this volume.

First, groundwater use in Central America seems to be following the development paradigms described by Shah and Kemper (respectively, Chapter 2 and Chapter 7, this volume). Agricultural groundwater use is generally still in stage I of their typologies, the stage before significant problems have emerged. While movement down the agricultural groundwater development path will likely vary from country to country and within countries, urban and industrial use surrounding metropolitan areas is already in stages II or III, and aquifers are showing clear signs of stress.

Second, as in most of the other regions described in this book, Central America has a great vacuum regarding information on groundwater. This applies to information on the resource itself as well as on its use. Failure to create, centralize and share information means there is little basis for management and decision-making in the already stressed urban areas, as use in some areas could lead to scarcity in the future. Moreover, there is only limited information on the potential for additional agricultural development, as the information that is available is not always consistent across countries, making it difficult to establish a regional information and lessons-sharing system.

Third, as in most of the other regions described in this book, the majority of Central American countries have either no water laws or only obsolete laws with little practical application. For this reason, the groundwater governance problems already occurring in South Asia and China are also occurring in Central American cities and may impact agriculture in the future. Connected to the governance problem is the growth of cities, particularly capital cities, over the highest potential aquifers. While use of groundwater in urban areas has clear benefits, the absence of land regulation and planning has meant that many cities have expanded into recharge areas, threatening the water that helped the cities' existence in the first place. Lack of control over industrial and human contaminants is increasingly threatening water quality. Uncontrolled agricultural chemical use is high throughout the region with concomitant risks to groundwater quality through percolation. To date, measurable concentrations do not generally exceed permissible limits, but pollutants are being detected, meaning that concentrations are increasing.

Clearly there has been no 'agricultural groundwater revolution' in Central America; nor is there likely to be one in the future simply because of climatic conditions. None the less, there are critical connections between agriculture and groundwater in Central America, though the importance of these connections is not the same as in regions where direct agricultural use is much higher. It is the study of this contrast that can help us to understand how broad the connections between agriculture and groundwater can be.

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