CASOS DE CONTAMINACIÓN POR INTRUSIÓN SALINA EN ACUÍFEROS COSTEROS DE LA PENÍNSULA DE NICOYA (COSTA RICA)

Abstract

The coastal aquifers of the north Pacific region of Costa Ricas are being used to supply the water for tourism, agriculture, and to meet the needs of the local population. The hydrodynamic characteristics ofthese areas are not well known, although the production of water from these aquifers is critical given the increasing demand for the water. The zones under investigation are located in a moderately to very dry tropical regioncausing there to be a limited the supply of the water resource.Twenty four water reservoirs were identified in the Nicoya Península of Costa Rica containing discharge wellswith a variable production of 0,08 to 20 liters per second, a thickness of 10 to 30 meters, and a transmissivityof 2,5 to 2200 square meter per day. Compared to other volcanic continental aquifers in the region, these aqui-fers have a moderate potential of water production. The over-explotation and the reduction of the recharge caused the drawdown of the water level of many wells and provoked salt intrusion in 15 wells.To adequately manage the groundwater resource, it is neccesary to rationalize the comsumption of the water ba-sed upon its use. Potable water usage must be limited to drinking and other necessary household activities. Whereas recycled water can be used to meet the needs of other activities.