Abstract: The main spillway of lake Oroville was found damaged on February 7, 2017. In the subsequent days, the incident was exacerbated and eventually caused a massive evacuation of local residents. The damage of the main spillway was caused and aggravated by relatively poor geology condition, thin chute, inadequate concrete strength and inattentive inspections. A series of inappropriate emergency operations forced the emergency spillway being used, causing excessive erosion at the base of the weir of emergency spillway, which threatened to undermine and collapse the concrete weir. Fearing the collapse, an evacuation order was issued by the local government and 188 000 people in the vicinity were evacuated.

Key words: Oroville dam, spillway, damage of chute, emergency operations, massive evacuation

摘要： 2017年2月7日，美国奥洛维尔水库主溢洪道泄槽局部发生破损，此后事态逐步升级，最终导致下游18.8万人紧急撤离。主溢洪道地质条件较差、结构较薄弱、混凝土材料强度偏低，加之日常检查维护工作不到位，导致了破损的发生和快速发展。而应急调度失误致使非常溢洪道被动启用，进而导致其过流区山体严重冲刷、危及混凝土溢流堰稳定性，直接迫使大规模人口撤离。

关键词: 奥洛维尔大坝, 溢洪道, 泄槽破坏, 应急调度, 强制撤离