Dique El Cadillal, Reservoir dam in Tucumán Province, Argentina

Dique El Cadillal, also called Dique Celestino Gelsi, is a reservoir dam on the Salí River in Tucumán Province, Argentina. The dam is made of earth and rock with a clay core, and its reservoir is the largest body of water in the province.

The first studies for the dam began in 1889, but construction did not start until 1962 and was completed in 1965. It was privatized in 1996, when Hidroeléctrica Tucumán S.A. took over its operation.

The village of El Cadillal has an archaeological museum and a replica of a Greek amphitheater, showing the local interest in both history and outdoor performance. Visitors often come here to fish for silversides, a tradition protected by seasonal bans.

The area around the dam is easy to explore on foot or by bike, with paths leading to viewpoints over the water. It is best to visit during the day, as some services may be limited in the evening.

The dam's reservoir loses storage capacity because of sediment carried down from upstream agriculture, a problem that has been monitored for years. A special raft is sometimes used to pump water directly to the treatment plant when sediment levels are high.