This paper presents a method to include damage at the initial stage of coastal flooding events definition and in return periods computation. The methodology is illustrated within a local study carried out in Biarritz Grande Plage, a meso-tidal, wave dominated beach located on the french basque coast in the south west of France. The work is based on two datasets covering the period 1949–2015: a first one, consisting of observation and synthetic data on wave characteristics and water level, and a second one, gathering storm dates and related damage intensities obtained through investigations in the press and in archives. A statistical analysis was first carried out to find the best combination of source variables explaining the reported damages for the identified storms. Maximal, mean and accumulated values were calculated over storm duration, considering source and aggregated variables based on the empirical run-up formula or the wave energy flux. Most rules combining a wave parameter and water level are found to provide satisfactory damage prediction as soon as maxima variables are considered. Rules based on mean variables are less accurate and those based on accumulated variable values are not relevant. The ability of the rules to be used as generic event definition rules is then tested by performing a retrospective analysis on the whole dataset, checking their efficiency in detecting historical storms (i.e., with damages) without finding too many false positives. Most of the rules formerly studied, except the ones using wave period only as wave parameter, were able to correctly perform this task. Coastal flood event return periods (RP) were then calculated by applying three of the best rules identified previously. The rule using non simultaneous maxima of wave energy flux and water level gives encouraging results for the RP values. Nevertheless, the discrepancy still observed among the different rules calls for further work in this direction.

本文提出了一种在沿海洪灾事件定义的初始阶段和返回期计算中包括破坏的方法。在Biarritz Grande Plage进行的一项本地研究中说明了该方法，Biarritz Grande Plage是中潮汐波主导的海滩，位于法国西南部的法国巴斯克海岸。这项工作基于涵盖1949-2015年期间的两个数据集：第一个数据集，包括有关波浪特征和水位的观测和综合数据，第二个数据集收集了通过新闻界和新闻界调查获得的风暴日期和相关破坏强度在档案中。首先进行了统计分析，以找到源变量的最佳组合，这些变量解释了已报告的暴风雨所报告的损失。计算了风暴持续时间的最大值，平均值和累积值，根据经验上升公式或波能通量来考虑源变量和集合变量。一旦考虑了最大变量，发现将波浪参数和水位结合在一起的大多数规则可以提供令人满意的破坏预测。基于均值变量的规则准确性较低，而基于累积变量值的规则则不相关。然后，通过对整个数据集进行回顾性分析来测试这些规则用作通用事件定义规则的能力，检查其在检测历史风暴（即有损坏）时的效率，而不会发现太多的误报。以前研究的大多数规则，除了仅将波浪周期用作波浪参数的规则外，都能正确执行此任务。然后，通过应用先前确定的三个最佳规则来计算沿海洪水事件的返还期（RP）。使用波能通量和水位的非同时最大值的规则为RP值提供了令人鼓舞的结果。尽管如此，不同规则之间仍然存在差异，需要朝这个方向做进一步的工作。