The upper reservoir storage tank (20,000 cubic m, 200 ft diameter, 35 ft tall) for the 9.7 MW Choloma project is reported by the manufacturer, TIPIC SA, to be the largest steel water tank in Central America. An innovative, collaborative effort combines six rivers, six intakes, one steel tank and a powerhouse to create the 9.7 MW Choloma hydroelectric project in Guatemala. This article describes the design and construction process for a new and innovative 9.7 MW hydroelectric