Simple download service (Atom) of the dataset: Centennial flood of Orconté — Orconte sector in Frignicourt

Area exposed to one or more hazards represented on the hazard map used for flood risk analysis.
The hazard map is the result of hydraulic modelling carried out in 2018 by the hydratec design office, whose objective was to assess the intensity of the hazard at any point in the study area. The assessment method led to the delimitation of a set of areas on the study perimeter, constituting a graduated zoning based on the level of water heights of the hazard. The assignment of a hazard level at a given point in the territory takes into account the probability of occurrence of the dangerous phenomenon (the centennial flood) and the natural terrain of the area.
All hazard areas shown on the hazard map are included. Areas protected by protective structures are represented (possibly in a specific way) because they are always considered subject to hazard (case of breakage or inadequacy of the structure), here we speak of hydraulic transparency.
Hazard zones can be described as developed data to the extent that they result from a synthesis using multiple sources of calculated, modelled or observed hazard data. These source data are not concerned by this class of objects but by another standard dealing with the knowledge of hazards.
Some areas of the study area are considered “zero, insignificant or white zones”. These are the areas where the hazard has been studied and is nil. These areas are not included in the object class and do not have to be represented as hazard zones.

Genealogy:
The boundaries of a hazard zone are shown on the hazard map depending on the level of the hazard. In other words, the polygon objects representing the hazard zones form a partial coverage of the area studied, each of which is a closed polygon in which hazards have the same intensity level. In other words, the criterion for dividing the hazard zones is the level of the hazard.

The retained water surfaces come from the IGN BDTopo represented in the dataset N_SURFACE_EAU_BDT_ED181_051.

Operating scale 1/10000

用于洪水风险分析的灾害地图中，标注了暴露于一种或多种灾害的区域。
该灾害地图由hydratec设计事务所于2018年开展的水文建模成果生成，其核心目标为评估研究区域内任意点位的灾害强度。本次评估通过在研究范围内划定多片区域，基于灾害水位高度等级构建分级分区体系。确定某一区域点位的灾害等级时，需综合考量危险现象（百年一遇洪水）的发生概率与区域自然地形条件。
灾害地图所标注的全部灾害区域均已纳入本数据集。受防护结构保护的区域亦会被标注（可能采用专属表达方式），因此类区域仍需纳入灾害考量范畴（例如结构溃决或防护不足的场景），此即所谓的“水文透明性”原则。
灾害区域可被视为经整合后的数据集，其源于对多源计算、建模或观测所得灾害数据的综合合成。此类源数据不属于本对象类别的范畴，而归属于另一项涉及灾害认知的标准规范。
研究区域内部分区域被归类为“零值、无意义或空白区域”，即经评估灾害程度为零的区域。此类区域未纳入本对象类别，亦无需作为灾害区域进行标注。

谱系关系：
灾害区域的边界依据灾害等级标注于灾害地图之上。换言之，代表灾害区域的多边形对象构成研究区域的部分覆盖范围，每个多边形均为闭合区域，其内灾害强度等级完全一致。换言之，灾害区域的划分依据为灾害等级。

所纳入的地表水域数据源自法国国家地理研究院（Institut Géographique National，简称IGN）BDTopo，对应数据集编号为N_SURFACE_EAU_BDT_ED181_051。
作业比例尺为1/10000。