After completing scores of working pits, many construction units have excavated the pilot tunnel for the main waterway tunnel a total of 10,000 meters and enlarged it through one thousand and hundreds meters.

Soldier-builders have increased the proportion of the pit work by machines to the maximum and introduced advanced blasting methods, so as to speed up the tunneling.

And Pyongyang City Brigade, Jagang and North Hamgyong provincial brigades and other units in charge of the waterway tunneling have applied new technologies to increasing the number of blast holes and raising the blasting efficiency, thus driving the pilot tunnel over 100 meters on a daily average.

Meanwhile, the field headquarters directs efforts to supplying equipment and materials necessary for the fast excavation of the pilot tunnel.