In December 1984, the feasibility report for Porce III was submitted and complementary studies were carried out between 1986 and 1996.

It is controlled by four radial gates and has a maximum discharge of 10,850 cubic metres per second (383,000 cu ft/s).

The catchment area for the dam and reservoir is 3,756 square kilometres (1,450 sq mi).

At the end of the lower headrace, it converts into four penstocks to supply each of the underground power house's 211 megawatts (283,000 hp) Francis turbines with water.

Once ejected from the power plant, it enters over 1,000 metres (3,300 ft) of tailrace tunneling and is returned to the Porce River.