Flood-prone area of the United Weißeritz (WMS service)

The area at risk of flooding, presented in map form, is based on Section 75(1) No.1 and Paragraph 2 of the SächsWG. It is an area that is flooded only when a flood event is exceeded, as is statistically expected once in 100 years. Pursuant to § 75(2) sentence 2 SächsWG, the extreme event became in accordance with the hazard map of the flood protection concept for the Weißeritz (responsibility: Free State of Saxony, state dam obsolete) used. It corresponds to the flooding area of the Weißeritz floods of 12-13 August 2002. The recurrence interval of this event was carried out by the LfULG at the age of 500 (Saxon State Office for Environment and Geology; Event analysis Floods in the Easter Mountains in 2002; (July 2004) indicated that the flow rate was expressed at approximately 450 m³/s. It was the largest flood of the Weißeritz to date. The flow rate was approximately 1.5 times the largest flood of July 30, 1897. In June 2013, the fourth largest Weißeritz flood occurred since observation began. The flow rate was between 150 and 170 m³/s and the final evaluation by the competent authorities of the Free State is still pending. By 2020, the United Weißeritz will be expanded in Dresden in such a way that a flood as in August 2002 can be discharged without large expanses in the riverbed. The efficiency of the water bed is currently approximately HQ100 (flow rate 234 m³/s). Until then, in the event of extreme events, large-scale floods can still be expected and, as a result, risks and impairments to the well-being of the general public and public security and order (endangering life or significant damage to health and property). According to Section 75(5) of the SächsWG, planning and construction measures adapted to the risk must be taken in order to prevent damage caused by penetrating water as far as possible. In particular, structural measures must be taken to prevent the presence of hazardous substances in the event of floods.本以地图形式呈现的洪水风险区域，依据《萨克森州水法（SächsWG）》第75条第1款第1项及第2款制定。该区域仅在超出百年一遇统计预期的洪水事件发生时才会被淹没。 根据《萨克森州水法》第75条第2款第2句，本次极端事件匹配所采用的魏瑟里茨河（Weißeritz）防洪规划灾害地图，责任主体为萨克森自由州，州属大坝已废弃。该区域对应2002年8月12日至13日魏瑟里茨河洪水的淹没范围。 本次事件的重现期经萨克森州环境与地质国家局（LfULG）测算为500年一遇（详见《2002年厄尔士山脉洪水事件分析》，2004年7月），其流量约为450立方米/秒。这是迄今为止魏瑟里茨河发生的最大规模洪水，流量约为1897年7月30日最大洪水的1.5倍。 2013年6月，魏瑟里茨河发生了有观测记录以来的第四大洪水，流量介于150至170立方米/秒之间，萨克森自由州主管部门尚未完成最终评估。 截至2020年，德累斯顿境内的联合魏瑟里茨河河道将完成拓宽改造，使得2002年8月量级的洪水可通过河道顺利宣泄，避免大面积漫溢。当前河道的行洪能力约为百年一遇流量（HQ100），即234立方米/秒。在此之前，若发生极端洪水事件，仍可能出现大规模漫溢，进而对公众福祉、公共安全与秩序造成风险与损害（包括生命威胁、严重健康损害及财产损失）。 根据《萨克森州水法（SächsWG）》第75条第5款，需制定并实施适配风险的规划与建设措施，尽可能避免透水引发的各类损害。尤其需采取工程措施，防止洪水发生时危险物质泄漏扩散。