Cavico subsidiary Cavico Bridge and Tunnel is set to make the third and final tunnel breakthrough at the A Luoi Hydropower project in Vietnam next month.
Once complete, the 170MW hydropower plant is expected to generate about 686 million kWh of energy annually.
In 2007, Cavico was awarded a contract to excavate the headrace tunnel and four sub-tunnels, a surge tank, a vertical shaft and a service access road for the project.
The firm created a 7.27 mile-long and 21.3 feet-wide headrace tunnel and broke through the first and second sub-tunnels in August and December last year.
The plant, built on the A Sap River in Thua Thien Hue Province in central Vietnam, is owned by Central Hydropower.