The Songhua River system (see Fig. 1, right) originates from Tianchi of the
Changbai Mountain in Jilin in northeastern China. The main stream of the Songhua
River system runs through the center of Harbin City (the provincial capital of Heilongjiang
Province; see Fig. 1, left) from west to east and is the biggest basin for
irrigation in this city. Most rivers in and around Harbin City belong to the Songhua
River system. The Songhua River system has obvious seasonal dynamics, as there is
abundant rain in summer (from June to September) accounting for about 70% of total
rainfall in a year, whereas in winter River system remains frozen for almost four
months (from December to March).