The reservoir lies 96 km south east of Copiapó and 83 km from Amarilla, beside the Acueducto Amolanas. It is the only reservoir built in the valley of the Río Copiapó, and has functioned for the benefit of the valley since 1920.
It was initially constructed of earth. The waters that run into the reservoir come from the Manflas, Jorquera and Pulido rivers.
It can hold up to 23 million cubic meters of water, which allows for the regulation of the irrigation channels within the Copiapó valley.
The greatest flow of water occurs in October, when the snow in the mountains thaws.