Colombia’s state-controlled power-generation company Isagen announced this week it had finalized financing for a $1.74-billion, 820-MW hydroelectric plant under construction on the Sogamoso River in the Dept. of Santander. Isagen officials said they collected $813 million in loans from local banks to finance the project. In December 2009, a consortium led by the Italian firm Impregilo and including Colombian companies Conalvias and Tecnica Vial netted the $500-million, first-phase contract involving construction of a 190 meter-high, 300-m-long, concrete-faced, gravel-filled dam and underground power station. The plant is slated to go on line in 2014. Impregilo is already doing preliminary work for
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.