Four giant reservoirs were built, each with a diameter of 50 meters, a height of 22 meters and a capacity of 35 thousand cubic meters, yielding a total volume of 140,000 m3. The large-capacity reservoirs are recessed and covered with soil. The thickness of their bottom is 1.2 m at the widest edge, whilethe walls have a thickness of 0.6 m. These are pre-stressed reinforced concrete structures. The roof of each reservoir, with a weight of 1,450 tonnes, is made up of a dome shaped, spherical canopy with a height of 4.79 m. It was concreted at the reservoir bottom and subsequently lifted by 20 m using a hydraulic system. The average lifting speed was 50 cm per hour, whilethe entire liftlasted 4 to 5 days, including monitoring and measurements.