National Geographic : 1919 Sep
Photograph from C.K.Edmunds NATIVE ENGINEERS DIRECTING SHANTUNG COOLIES IN CURBING THE YELLOW FLOOD OF"CHINA'S GREAT SORROW" The last serious breach in the dikes, which in normal times control the waters of the Hwang-ho, occurred inSeptember, 1902, near Liu-Wang Chuang, and was 1,500 yards wide. Through it most of the river flowed. It was repaired by building out from each side dams intheform ofa series of pakwerks of kaoliang stalks and sacks of clay, each pakwerk or buttress being joined to theprevious one byropes and piles. Bythis means the breach was reduced to 55 feet, and this, after two destructive attempts in which the lives of many workmen were lost, was effectively closed on March 16, 1903 (see illustration on opposite page), when a huge mattress was successfully swung into position. This turned theturbu lent waters back into their proper channel. The rush through the opening was previously reduced bythe construction ofadeflecting groin onthe up-river side of the breach, constructed like the pakwerk, and projecting some 120 feet into the current. The width oftheriver channel abreast of the breach had been 60o feet, but was reduced to 300 feet by the formation of a sand bank on the opposite side oftheriver.