YICHANG - The Three Gorges Dam, the world's largest hydropower project, will work at full capacity by the end of May, when the last two power units will become operational, Chen Fei, general manager of the China Three Gorges Corporation, said Saturday.

Including the four 700,000-kilowatt power units starting to generate electricity last year, the six units are situated inside the mountain on the right side of the river bank.

Construction on the underground hydropower station in central China's Hubei province began in July 2001 to harness the power of the water discharged during flood season on the Yangtze River, China's longest waterway.

The Three Gorges Project, launched in 1993 with a budget equivalent to $22.5 billion, consists of a dam, a five-tier ship dock and a total of 32 hydropower turbo-generators.

The 26 generators on the two sides of the dam had gone into operation as of October 2008, with each unit having a generation capacity of 700,000 kw.

The project generates electricity, controls flooding by providing storage space and adjusts shipping capacity on the river.

Last year, it generated 78.29 billion kilowatt-hours of electricity.

It also withstood three major floods last summer, taking the edge off the fierce flows by holding back the majority of the flood water in its reservoir to ease the flood's impact on the river's lower reaches.

The dam reservoir releases water in the dry season to ease droughts, particularly in downstream rice-growing areas.