Water uses and sources

Overall water extraction in Central America is about 19,000 million cubic metres or less than 3% of the total water availability (Table 6.1). Per capita extraction is estimated at 656 m3/year. Costa Rica has the greatest extraction, both in total and per capita, but it still amounts to only 5% of total available supplies.

Agriculture is the main user of extracted water in the region, with a per capita consumption of approximately 2200 m3/year (excluding Belize and El Salvador for which data are not available). Most of agriculture uses surface water as supplemental irrigation during the dry season (Losilla et al., 2001). Agricultural use is followed in importance by domestic consumption and industrial demand. By the statistics in Table 6.1, agriculture accounts for more than 80% of use. However, figures for the industrial sector are likely underestimates. The primary reason for the underestimate is poor information on groundwater abstraction. The main source of water for industry is groundwater, and there is no system for concessions or inventories that would make it possible to measure, or control, consumption levels. Also omitted from the estimates are environmental water use and the generally non-consumptive use of water for tourism and hydroelectric power.

In addition to its use in industry, groundwater from springs and wells also accounts for an estimated 50-95% of the water being used in the public (domestic) supply system (Losilla et al., 2001). One reason for the high utilization of groundwater is that the majority of surface supplies are of insufficient quality due to poor land-use practices and poorly planned urban expansion. Groundwater is particularly important for domestic supply in Belize, where it accounts for 95% use. Groundwater is similarly important for domestic supply in Costa Rica. In fact, groundwater accounts for almost 88% of Costa Rica's extraction to satisfy all consumptive demands, i.e. all uses with the exception of hydroelectric generation.

Table 6.1. Central America: water resources and use.

Total water

Per capita

Total

resources

water

extraction

Per capita

Per capita extractionc (m3/year)

Extraction as

Rainfalla

(million

resourcesb

(million

extractionc

a percentage

(m/year)

m3/year)

(m3/year)

m3/year)

(m3/year)

Domestic

Industry

Agriculture

of resources

Belize

1.5-4.6

15,258

58,458

101

389

-

-

-

0.7

Guatemala

2.2

111,855

8,857

2,702

21 4

33

36

1 45

2.4

Honduras

1.9

90,031

13,776

1,745

267

37

10

220

1.9

El Salvador

1.2

18,616

2,755

797

118

-

-

-

4.3

Nicaragua

1.0-4.0

195,238

34,672

1,759

312.3

59

2.4

250.9

0.9

Costa Rica

3.3

118,720

27,967

6,032

1421

158

76.4

1,187

5.1

Panama

3.0

156,259

49,262

59,316

1870

1 453

14

403

38.0

Central America

705,976

27,965

19,069

656

-

-

-

2.7

information taken from each country report. bWorld Bank (2005).

cCRRH-SICA, GWP-CATAC-UICN (2002).

information taken from each country report. bWorld Bank (2005).

cCRRH-SICA, GWP-CATAC-UICN (2002).

For Costa Rica, projections for water demand for all uses by 2020 are estimated to reach 39 km3, equivalent to 35% of the total water resources in the country. Even so, urban development continues to increase the pressure on water resources, regardless of the policies for conservation and protection adopted by the country. In some regions, signs of conflict and competition for water use are already being observed. In conclusion, the use of water, groundwater in particular, is becoming increasingly more complex every day.

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