Dong Nai 3 and Dong Nai 4 hydropower plants were built in 2004, within the two provinces of Lam Dong and Dak Nong. The two power plants have a total capacity of 520MW, of which Dong Nai 4 is 340MW and Dong Nai 3 is 180MW. The total output of electricity is 1.7 billion kWh/ year supplied to the national grid.
Dong Nai 3 hydropower plant separates Dong Nai River by a main dam in RCC structure, 572m long, 10m wide and 107m high. This dam is 595m above sea level, creating a reservoir volume of 1.69 billion m3 with surface area of 55,181 km2. The spillway consists of five gates and the maximum discharge capacity (five completely open gates) is 10,188 m3/s.
Dong Nai 4 hydropower plant is downstream from the Dong Nai 3 hydropower plant, with a reservoir created by the main dam 481m long, 10m wide, and 127.5m high. The dam is 481m above sea level, with a reservoir volume of 332.1 million m3 and a surface area of 8.33 km2. The spillway consists of five gates, the maximum discharge capacity (5 completely open gates) is 10,188 m3/s.
These hydropower plants are among the important constructions of the country to generate electricity, to contributively reduce flood for downstream area, as well as to create landscape and conditions for navigation and aquaculture, etc.