The main methods for calculating designed flood are probable maximum precipitation and hydrologic frequency analysis.

设计洪水计算方法主要是可能最大降雨和水文频率法。

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Analysis of flood release capacity of upstream detention areas and the probable maximum flood reveals that the risk of levee-breach in Harbin city still exists.

对哈尔滨上游蓄滞洪区的分洪能力以及可能发生的最大洪水进行了计算和分析，得出的结论认为哈尔滨市未来仍有发生溃堤的可能。

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Berkley said industry risk models have all but abandoned the once common indicator known as "Absolute Maximum Loss, " preferring to base premiums on the more conservative "Probable Maximum Loss" calculation, which lowers damage estimates by factoring in long odds of catastrophic events.

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