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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The designed discharge and designed flood level are determined by hydrological computation and main characteristic value of highway bridge is checked.

通过桥渡水文计算，确定了设防流量及设防水位，校核了大桥主要特征值；

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Designed flood of reservoir is a typical flooding process under given engineering safety standard. The frequency of designed flood is regarded as hydrological risk.

水库设计洪水就是在给定工程安全标准情况下某个典型洪水过程，设计洪水的频率特征表现的就是其水文风险。

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The same drawback, of course, applies to dams designed for flood control.

ECONOMIST: The Mekong river

In Pakistan, for example, the International Centre for Water Hazard and Risk Management (ICHARM), created under the auspices of UNESCO, and the Japan Aerospace Exploration Agency (JAXA) designed the Integrated Flood Analysis System (IFAS), a risk-prevention system using data obtained via satellite.

UNESCO: Published in Mainichi Newspaper on 21 May 2012.

The Elwy reached its highest recorded level breaching flood defences designed to cope with a one in 100-year event, says the report.

BBC: St Asaph floods cost council house insurers ?1m