El Diquís Hydroelectric Project

The El Diquís Hydroelectric Project (known as the PHED for its Spanish acronym) is a cancelled hydroelectric dam project, designed by the Instituto Costarricense de Electricidad (ICE, the Costa Rican Electricity Institute).

The dam was to be located on the Térraba River between Buenos Aires, Osa, and Pérez Zeledón in Puntarenas Province in southwestern Costa Rica. Planned as the largest hydroelectric dam in Central America, the 631 MW El Diquís Hydroelectric Project would have generated renewable electricity for more than one million consumers, dwarfing both the Reventazón Dam that opened in 2016 and the Pirrís hydroelectric plant, completed in 2011. The $2 billion PHED project would have required 7363.506 hectares of land, 915.59 hectares of which are indigenous territories, and displaced 1547 people. The population across the entire region is very sparse. There is almost no industry, employment opportunities is largely restricted to farms for coffee and pineapples, and some tourism. It would have employed in the region of 3,500 people and the electricity produced had the potential to be exported to neighbouring countries.

The PHED was suspended indefinitely by ICE on November 2, 2018. In the announcement, the executive president of ICE, Irene Cañas, cited financial issues as a primary reason for the decision and also announced a series of adjustments to improve the financial conditions of the entity. Previously, in November 2016, the Costa Rican Supreme Court ordered a moratorium on the PHED until ICE completed a consultation with local affected indigenous communities, which it had been stalling on since 2011.

The PHED was to be part of the PPP - Plan Puebla Panama, now known as The Mesoamerica Project, or in Spanish Proyecto Mesoamérica - via SIEPAC.

The dam's electrical operating plant was proposed to have been built at Palmar Norte, some distance from the dam itself. The project included two tunnels. Palmar Norte is a small village located in the Térraba Valley. The region now continues to be served by an old conventional electrical plant at this village.