Costa Rica El Niño Plan Warns of Major Water Supply Risks

Costa Rica is preparing for possible water shortages affecting hundreds of thousands of people as the strong El Niño weather pattern continues to reduce rainfall across much of our country. A national contingency plan for the 2026-2027 El Niño period considers a worst-case scenario in which water production from important systems serving the Greater San José area could fall by as much as 45%. The systems include Orosi and Tres Ríos, which help provide drinking water to around 700,000 people in the Greater Metropolitan Area. The 45% figure does not mean authorities expect water production to definitely fall that far. It is a planning scenario being used to prepare for a prolonged drought if conditions continue to worsen. The concern has increased as El Niño has strengthened and rainfall totals have fallen well below normal across much of Costa Rica’s Pacific side and Central Valley. Between January and August, the North Pacific received about 37% less rain than usual. Rainfall was around 28% below normal in the Central Pacific, 25% lower in the South Pacific and 20% below normal in the Central Valley. Those shortages are already affecting some communities. Thirty-two community-run water systems in Guanacaste, Puntarenas and Alajuela have reported rationing in 74 communities, affecting approximately 6,525 homes and businesses. In some areas, wells and other water sources have lost significant amounts of flow. At least one community in Nicoya has reported a well drying up completely, while some residents are receiving running water for only a few hours per day. The national El Niño plan includes several measures intended to prevent similar problems from becoming widespread in the country’s most populated areas. Authorities are considering the use of emergency wells, including additional water sources in Guadalupe, W20 and La Florida. The plan also calls for faster repairs of leaks to reduce the amount of treated water lost through aging pipes. Controlled water rationing could be introduced if shortages reach certain levels. The plan sets out protocols for rationing when the water deficit exceeds 17%, along with tanker-truck routes to supply communities facing the most serious shortages. Costa Rica is also monitoring underground water supplies and could impose tighter controls on water concessions during periods of severe scarcity. The drought is not limited to drinking water. Lower rainfall can also reduce the amount of water available for hydroelectric power generation, which remains an important part of Costa Rica’s electricity system. If reservoir and river levels fall significantly, Costa Rica could need to rely more heavily on thermal power plants and electricity imports from neighboring countries. That could increase the cost of producing electricity. No electricity rationing has been announced, and the Costa Rican Electricity Institute has said it does not currently expect power interruptions. However, the national contingency plan includes preparations for a more severe scenario in which hydroelectric reservoirs reach critical levels. If electricity rationing ever became necessary, hospitals, clinics, schools and drinking-water systems that depend on electric pumps would be among the services given priority. The situation may appear unusual because Costa Rica has also experienced heavy rain, flooding and tropical waves during recent weeks. But short periods of intense rain do not necessarily erase a rainfall deficit that has accumulated over months. Some parts of Costa Rica are receiving considerably less rain than normal overall, even while individual storms can still produce flooding. The Caribbean is experiencing almost the opposite situation. Rainfall between January and August was about 42% above normal in the northern Caribbean and 38% higher in the southern Caribbean. That sharp difference between regions is one of the effects associated with the current El Niño pattern. The National Emergency Commission has already placed 23 municipalities under orange alert because of drought conditions, while dozens of others remain under yellow alert. El Niño could continue affecting Costa Rica well into 2027. For now, authorities are asking residents to use water and electricity carefully while they monitor rainfall, reservoirs, wells and community water systems. The most immediate shortages remain concentrated in parts of Guanacaste, Puntarenas and Alajuela, but the national plan shows that officials are also preparing for the possibility of more serious water problems reaching the Greater San José area if the dry conditions continue.