Builders from across the country, including the Thaechon Hydroelectric Power Station Construction Company, set about the excavation and filling work all at once.

Those from Pyongyang City carried out five blasts in a day to the maximum, moving away nearly 1,000 cubic meters of bedrock, earth and sand.

Builders from South Phyongan Province finished 10 percent of the ground excavation work for a generator building in some 20 days after they began buckling down to the project.

The Ministry of Railways is in charge of the cofferdam project needed for generator building, inlet channel and drainage projects.

South Hwanghae and South Hamgyong provinces sped up ground excavation for generator buildings while Jagang Province made upsurge in tunneling and drainage construction.