乌鲁木齐河“960719”洪水分析

本文依据大量实测洪水数据对乌鲁齐河“９６０７１９”洪水的来源，特点及时空分布变化进行了讨论，分析了这场洪水的重现期，并提出了有关建议。

ANALYSIS ON THE FLOOD OCCURRED IN URUMQI RIVER ON JULY 19, 1996

A fierce flood occurred in Urumqi River on July 19, 1996, and brought about a heavy economic loss in the areas along the river, especially to Yuejin Steelworks located in Houxia valley, The peak discharge of the flood was up to 325m3/s, and it is the second largest one only next to the flood occurred in 1953.According to the analysis of observed data of rainfall and flood occurence, this flood was caused by a torrential rainfall and ice - snow melting. During July 18 to 20, the precipitation was over 100 and 60 mm in the alpine zone and mid - mountain zone respectively- About one half of the flood water was formed at the alpine zone which occupies 27. 9% of the total area of Urumqi River Basin, and about 1/3 of which was formed at the mid - mountian zone. From the mountainous area to plain, peak discharge of the flood reduced for 18% gradually and the discharge of the flood reduced for 40%.According to the analysis on flood frequency, the reoccurrence period of such flood is 30 years, the reoccurrence period of three - day flood discharge is 50 years in Urumqi River.