Alqueva Reservoir on Guadiana River, Portugal38.2N 7.5W
The Alqueva Dam is located on the Guadiana River in the Alentejo region. The reservoir it has created is Portugal and Western Europe’s largest. Here, the land west of the lake belongs to Portugal, while that to the east is part of Spain.
Alentejo is the driest and hottest region in Portugal, and persistent droughts are a problem. The climate and a lack of infrastructure have impeded economic development and isolated the area from the national and European economies.
The complex project was made to produce hydroelectric power, irrigation for farms in the surrounding area, as well as a large reservoir. Agricultural areas can be seen near the lake.
On February 8, 2002, the 96 metre high floodgates of the Alqueva dam were closed. In 2006 the lake was filled to the planned level, with a surface area of 250 km².
In 2004, the hydroelectric power station started to work, with a capacity of 240 megawatt. As of 2025 (though the endeavour is already slated to be finished by 2013), the lake should supply irrigation water for 1,100 km² in the Alentejo.