A division of construction and engineering conglomerate Song Da Corporation is building a 4km long hydroelectric tunnel 2,000m above sea level in a national park in the Vietnamese Central Highlands.
Work got underway on the site in June this year for the 2.3m diameter tunnel that will form the main outlet water tunnel for the dam that is being built further upstream for the Krong Kmar Hydroelectric Power Plant. The project has been designed by Electricity Vietnam (EVN), the state-owned agency that provides the country’s electricity supplies via a National Grid.
The project is located in the Chu Yang Sin National Park in the Krong Bong district of Dak Lak province. The region has traditionally relied upon coffee, fruit and rubber plantations to support its economy, but in recent years their has been increased interest in the region’s hydropower potential. The Krong Kmar plant with a designed output of only 150MW is typical of the smaller plants that are favoured for the area due to their minimal environmental impact. T&TI was told it is hoped the reservoir behind the dam will become one of the attractions of the Chu Yang Sin National Park in addition to its status as a wildlife reserve.
Tunnel contractor is Song Da 10.1 Joint Stock Co. who is supervised by the Ministry of Construction. It has opted for Japanese and Vietnamese pneumatic handtools to drill the chargeholes, with air power for drilling and shotcreting supplied by an Atlas Copco XAS 186 compressor. Blasting is typically carried out four times per week.
Excavated through limestone, the tunnel is due to be completed by May next year.
