Planning and development of Costa Rica water resources: current status and perspectives.

Abstract

This article describes the current status of water resources availability and demand in Costa Rica as well as the evolution of legal and institutional framework in the planning and management of this valuable natural resource.

Costa Rica, in its 51 100 km² of area, contains 34 national watersheds. The Caribbean slope equal to 46,4% of the country, while the Pacific slope to 53,6%. Costa Rica also has 34,3% of the territory in two transboundary basins; Rio San Juan with Nicaragua and Rio Sixaola with Panama. There are 12 hydroelectrical reservoirs which total 95 km² of area and 217 natural water bodies with 40,5 km² of area. The nationwide average annual water balance for the period 1970-2002 is: 3297 mm of rainfall, 2215 mm of runoff and 996 mm of evapotranspiration.  It is estimated that the potential water supply for Costa Rica is equivalent to 113 km³ of runoff and that the 2005 per capita’s Water Availability equals 26 221 m³/person/year. The nationwide groundwater usable volume is estimated to be 11 km³ of water, resulting in a sustainable flow of 350 m³ /s.  It is estimated that in 2005, withdrawals of water for various uses totaled about 22 km³ or 20% of the volume of available water. Water withdrawals for power generation accounted for 72% of the total, followed by agriculture with 21,2%. The use for human consumption, tourism, industry and agribusiness accounted for 6,8% of total removal and 88% of this volume comes from groundwater sources, highlighting the strategic importance of the protection and sustainable exploitation of the aquifers in the country. The water use projections for 2020 for all uses will reach 37,87 km³, equivalent to more than 33% of the total availability of water resources of the country.

The major problems are associated with the absence of a single institution with full responsibility for planning and management of water resources and that current water law is obsolete. Hence it is urgent to adopt a new water law with a modern vision to drive the reorganization of the sector, redefine a new water tariff scheme to fund research, development and resource planning and conservation. Without this legal tool, the country’s water resources will continue to be overexploited, creating imbalances and conflicts between social and productive sectors, increasing the vulnerability to pollution, overused and public health risks.