From 4 May to 8 July 2003

Zhangjiajie region of Hunan province experienced prolonged rainfall

with cumulative precipitation values exceeding 509 mm. The severe rainfall sequence started on July 8 with a high intensity storm that dumped more than 410 mm of rain in 12 h.On July 9

Zhuofu landslide was triggered

and resulted in a large-scale debris flow.A great deal of sediment transported by the debris flow deposited on the rail and jammed the river which made some disasters. The main reason that triggered debris flow was special topography

geological structure and unstable loose material state of the valley.The following factors that induced debris flow are a great deal of antecedent rainfall and intense short-duration rainfall.The emergency salvage treatment included cutting groove for drainage

reducing load

and renewing rails.Some measures

such as setting up drainage system

building slide-resistant piles

and constructing cut-andcover-tunnel

are taken to prevent and control debris flow.