Guri Dam

Construction on the Guri Dam (officially the Simón Bolívar Hydroelectric Plant) began in 1963, with the first phase completed in 1978 and the full expansion finished in 1986. The dam sits on the Caroní River in Bolívar state and impounds one of the largest reservoirs in South America by surface area. It was for many years the third-largest power plant in the world.

Guri produces roughly 60–70% of Venezuela's electricity in normal operating years, making it the single most important piece of infrastructure in the country. The dam's 20 generators are split between two powerhouses on either side of the spillway. Sustained drought conditions and a lack of maintenance investment have repeatedly caused major nationwide blackouts since 2010.

The 4,250 km² reservoir submerged a section of the Caroní River basin, including significant forested areas. The dam blocks fish migration and has changed downstream sediment patterns. As with most large hydroelectric plants, Guri displaces large quantities of fossil-fueled generation—roughly 40 million tonnes of CO2 emissions avoided per year compared to a coal-equivalent baseline.

Venezuela has experienced a series of catastrophic nationwide blackouts since 2019—several lasting more than a week—that the Maduro government has blamed on "sabotage" but that independent investigators have attributed to long-term maintenance failures and drought-induced low water levels at Guri.

• When commissioned in 1986, Guri was second only to Itaipu among the world's largest power plants.
• The reservoir is so large that it visibly affects regional rainfall patterns.
• In normal hydrology, Guri runs near 70% capacity factor; during the worst drought years it has dropped below 30%.