One of the most environmentally conscious nations in the world, in 2016 Costa Rica produced 98% of its electricity through renewable resources such as hydro, wind, and geothermal power. Created in the 1970s by building three dams on the Reventazon River, Cachi Lake is one of Costa Rica’s first hydroelectric projects. One of the dams, Cachi Dam, generates both electric power and 40% of the drinking water to the nearby town of Cachi. The water from the reservoir is diverted through a pressure tunnel over 3 ½ miles long, a surge tank, an 1857 foot long penstock including a 381 footlong steel-lined tunnel, and power house. The Cachi Dam also controls floods and creates recreational opportunities in the area, taking advantage of the head available in the river, which for about 40 miles creates white water suitable for rafting.

Lake Cachi reaches depths of up to 280 feet while Cachi Dam, a thin double-arch concrete structure said to be one of the thinnest such dams in the world, reaches heights of up to 260 feet above its deepest foundation. As a testament to its sound construction, during the 1991 Limon earthquake – the strongest recorded in Costa Rica’s history with a 7.7 magnitude – the Cachi dam did not suffer any damage even though the epicenter was just 53 miles away.

The Cachi Lake and Dam are free sights located about 9 miles (a 25 minute drive) northeast of Orosi. Casa de Sonador and Escalada Cachi are nearby attractions, and the ruins of Ujarras can be reached by continuing just three miles east of Cachi Lake via Route 224. Visitors to the dam on weekends will find vendors selling a variety of foods including freshly made fruit cocktails, crawdads boiled on the spot, meat kebabs, and buttered corn on a stick.