10 meters PPRi uncertainty band of Épernay sector CCGVM

The studies carried out in the context of the development of the Epernay PPRi (map of hazards) were carried out on the scale of 1/10 000th, and mapped on a background IGN scan25 enlarged to 1/10 000th. Since regulatory zoning stems from the intersection of the hazard map and the stake map, the accuracy of this mapping cannot be greater than that of the hazards. Consequently, the scale of use of the regulatory zoning is that of 1/10 000 and exploitation on a smaller cadastral scale (1/5000 or 1/2000) is not recommended. However, municipalities wishing to do so may transpose the regulatory map into their planning documents provided that they comply with operating principles in order to take account of the uncertainty associated with the expansion of the zoning, particularly at the boundary of the area. Indeed, it is not possible to improve the accuracy of the initial data which presents uncertainty about its contours of the order of 10 metres, which is relatively important on the scale of a plot in an urbanised area. The transposition of the regulatory map into a cadastral planning document cannot therefore be limited to a mere enlargement, which would result in a false precision of the contours. Therefore, a guide defines the principles that would allow municipalities who wish to do so, a transposition into an urban planning document (PLU, municipal map) taking into account the uncertainties between each area. It must also make it possible to define the area regulation to be applied when considering planning permissions. The hazard that made it possible to construct the Regulatory Zoning, as well as the stakes are located under gaspar No. 51DDT20170001 Spatial resolution: 1/2 500 Genealogy: The limits of the uncertainty band are not represented on the graphic documents of the RPP, they are not official in nature. The boundaries of the uncertainty band straddle the separation between two zones of the Regulatory Zonage, which do not follow cadastral or administrative boundaries. The width of this limit is set at 10 metres. A guide to the interpretation of this band sets out the principles for its operation.针对埃佩尔奈PPRi（灾害分布图，Epernay PPRi）开展的相关研究采用1:10000比例尺，并以放大至1:10000的法国国家地理研究院（IGN）scan25扫描影像作为底图。由于监管分区由灾害分布图与承灾体分布图叠加生成，其制图精度不得高于灾害图的精度。因此，监管分区的适用比例尺为1:10000，不建议采用更小的地籍比例尺（1:5000或1:2000）开展应用。但若地方市政部门有需求，可在遵循相关操作原则的前提下，将监管分区图纳入其规划文件，以考量分区范围扩展带来的不确定性，尤其是在区域边界处。 事实上，初始数据的精度无法提升，其轮廓存在约10米的不确定性，这在城市化区域的地块尺度下影响相对显著。 因此，将监管分区图纳入地籍规划文件的过程，不能仅通过简单放大完成——此举会导致轮廓精度出现虚假提升。为此，一份操作指南明确了相关原则，可帮助有需求的市政部门将监管分区图纳入城市规划文件（PLU，市政规划图），并考量各区域间的不确定性。该指南还需明确，在审批规划许可时应适用的区域监管规则。 用于编制监管分区的灾害数据及承灾体数据，其归档编号为gaspar No. 51DDT20170001。 空间分辨率：1:2500 数据溯源信息：不确定性范围的边界未在RPP的图形文档中展示，其本身不具备官方效力。不确定性边界横跨监管分区的两个区域分界线，且不与地籍或行政边界重合。该边界的宽度设定为10米。一份针对该不确定性范围的解读指南明确了其操作原则。