Water Availability
Jamaica is the third largest island in the Caribbean of approximately 11,000 square kilometers. 84% of its water resources come from groundwater captured in aquifers and the remaining 16% from surface water from rivers and streams. Although water demand is greatest in the basins on the south coast of the island (irrigation areas, urban centers and major industries), most of the available water resources are found in the basins on the north side of the island1.
According to the Water Resources Authority (WRA), the average annual rainfall is 21,5 km3/year. Of this amount, 50% (10,7 km3/year) is lost through evapotranspiration and the rest is distributed as surface water (5,3 km3/year) and groundwater (5,4 km3/year). However, Jamaica faces a number of challenges due to unequal distribution of rainfall, both geographically and temporally. Mountain ranges divide the island from east to west, resulting in higher rainfall in the north compared with the south due to rainshadow.
This variance in rainwater availability throughout the country has led to a dependence in some areas on groundwater extraction for meeting water demand. Over-pumping and saltwater intrusion is an area of concern.