Phu Ninh lake, 7 km from Tam Ky Town is a man-made reservoir constructed for storing water used mainly for irrigation with the capacity of nearly half a billion cubic meters of water.
The water surface area of the lake is 3,433 hectares and there are 6,000 hectares of that surround the lake with 30 beautiful islets and peninsulas. Construction of the lake started in 1977 and was completed 10 years later. It has satisfied the old-age dream of the people of Tam Ky and the neighboring areas supplying enough water for daily use and irrigation to the local rice paddies.
Besides the advantages of having irrigation, hydroelectric power, aqua- culture, forestry and the harmonization of ecological environment, the Phu Ninh Lake is also a promising area for future development of the tourist industry. During the hot summer months when the temperatures in Tam Ky sour into the low 30oC, the Phu Ninh Lake area remains cool because of the large water surface of the lake. The area contains many green "oasis" with various kinds of flora: 621 species belonging to 438 different branches, in which there are many valuable and rare species such as: erythrophloeum fordi, Southern Kingwood, and 170 species of pharmaceutical plants. The fauna of Phu Ninh area is also diverse with: 80 species of birds. 34 species of animals, 26 species of reptiles and some rare animals: Red-faced monkey, red wolf, horse bear, antelope, white head laughing thrush and dapple deer, pheasant... which are suitable for studies and ecological tourism. From the birds eyes view, the lake looks like a twinkling huge water frying pan.
Visitors can go around the oasis by motors boat and enjoy the poetic grandiose beauty of the boundless sky and water along with the greenery of the mountains and forest. In Chap Tra Valley, in the middle of the quiet surface of the lake, there is an "open cast" mineral water spring. This pure water stimulates the human digestion, elates ones mind and is effective in the treatment of diseases relating to liver, bladder, muscle and joints. In the near future, Phu Ninh tourist resort will dome into being, with many diverse forms of tourism: Outing, sight-seeing, fishing, swimming, sliding and mineral water bathing for the treatment of diseases.
On March 29th, 1977, the people of Quang Nam-Da Nang commenced the construction of the great project at Phu Ninh. After ten years of creative and persitent work, with support from the central government, the project was completed on March 27th, 1986. It consists of a 3,000 – ha reservoir holding 500,000 cubic metres of water, and thousands of kilometres of channels and ditches.
Twelve works help block the flow of the Tam Ky River. There are 50 kilometres of main channel, 427 kilometres of grade two channel and many supplementary ditches. Over 1,400 bridges, culverts and other works are incorporated in the scheme.
Lake Phu Ninh has helped to realise the dream of the local people-the irrigation of 80% of the rice fields and flood mitigation for the town of Tam Ky and surrounding areas. Apart from irrigation, Lake Phu Ninh provides an annual output of between 1.5 and 3 million Kwh from its hydro-power station, and 60 tonnes of fish and fresh water shrimp. The large lake helps to cool the air, attracts many birds from the coller regions and provides diverse vegetation. Even in the hottest season, the air is always cool, pure and fresh and is suitable for tourism, fishing, boating, swimming and recuperation. Some facilities have recently been built in the beautiful natural landscape. Transport is available to the easily accessible Phu Ninh Tourist and Convalescent Centre, which is only 70 kilometres to the south of Da Nang.