Although the government has not yet reached an agreement with indigenous groups who are opposed to the dam, they have announced that the reservoir will be temporarily filled in order to carry out tests.

From a statement issued by the National Public Services Authority:

The filling up of the reservoir is temporary and for testing purposes only. The final filling up and the operation will not begin until the agreements from technical roundtables have been finalised.

The National Authority of Public Services reports that the Barro Blanco hydroelectric plant, owned by the company Generadora del Istmo, S.A., will start filling its reservoir in the period between May 24 and August 3, 2016. This filling up is temporary and will allow for the testing needed to examine the elements of this power plant and its connection to the national electricity system.