HUNG-TSE LAKE

Wade-Giles romanization Hung-tse Hu, Pinyin Hongze Hu, large lake in the Huai River valley, on the border between Kiangsu and Anhwei provinces, China. Tradition has it that until the early 7th century its name was Po-fu-chien Lake and that it was given the name Hung-tse Lake by Emperor Sui Yang Ti (reigned AD 604617) of the Sui dynasty (581618). In T'ang and early Sung times (from the 7th to the 10th century) it was smaller than its present surface area of 757 square miles (1,960 square km), probably less than a third of its present size. It was also separated from the main course of the Huai River, which flowed to the south and southeast of the lake. The Huai was shallow and difficult to navigate; and in the 11th century, under the Sung dynasty (9601279), various canals were constructed to make use of the lake as a part of the canal system between K'ai-feng (in Honan province) and Ch'u-chou (modern Huai-an in Kiangsu province), joining the lake to the Huai. When, in 1194, the Huang Ho changed its course to the south to join the Huai at modern Ch'ing-chiang (Kiangsu), it usurped the lower course of the Huai, which no longer had a direct outlet to the sea. The waters of the Huai discharged into Hung-tse Lake, which then grew to its present size, inundating a vast area of fertile irrigated land. The surplus waters of the lake flowed southeast, via the Kao-pao and Pao-ying lakes and the channel of the Grand Canal (Ta-Yn-ho) to the Yangtze River (Ch'ang Chiang), east of Yang-chou (Kiangsu). The lake is very shallow, and, in the course of centuries, its bottom silted up. By the 19th century, flooding in the area was frequent and severe. In the 1930s a new channel was dug from the eastern shore of the lake direct to the sea. This canal was restored and improved in 195152 under the name of the Su-pei Canal, and, together with the comprehensive water conservancy project for the Huai River valley, it has reduced the incidence of flooding. The lake surface is only some 50 feet (15 m) above sea level, however, and drainage remains a problem. Most of the lake is too shallow for any but very small boats.