Within the wide array of adaptive responses to flood hazards, planned relocation of residents at risk is usually only taken into account if other responses are ineffective or unavailable. Residents targeted by planned relocation are confronted with radical changes in their livelihood; therefore, relocation is highly contested within public risk discourse. The present paper assesses dynamic processes in the design and implementation of voluntary planned relocation in the Austrian Danube catchment over five decades. Using the Multiple Streams Approach, the emergence of policy windows is mapped to developments in the problem, political, policy and population streams. A mixed-methods design combines semi-structured interviews of 88 affected households and 21 decision-makers with archival research. Repeated flood events underscored that standard protection did not suffice for all riverside communities. In consequence, national authorities acted as policy entrepreneurs to advocate planned relocation and direct the discourse; by contrast, local stakeholders and residents played a mostly passive role. The relocation policy developed from ad-hoc informal arrangements towards a formalised procedure. Relocation governance evolved as incremental change over a long time span instead of immediate, radical disruption. Policy acceptance by residents depended crucially on social learning and on coincidence with personal circumstances and biographical stages. Policy windows opened for several years, when pre-signals from ongoing public debate accumulated and the different timescales in the decision-making of public administrators, elected representatives and residents aligned. Key factors were long-term perspective, flexibility, engagement and social capacity at a local level to deal with and manage planned relocation.

在对洪水灾害的各种适应性应对措施中，通常只有在其他应对措施无效或无法利用时，才考虑对有风险的居民进行有计划的安置。计划搬迁的居民面临着生计的巨大变化；因此，在公共风险话语中，搬迁备受争议。本文评估了在奥地利多瑙河流域的自愿性计划搬迁的设计和实施过程中的动态过程，该过程在过去的50年中一直存在。使用多重流方法，政策窗口的出现被映射到问题，政治，政策和人口流的发展。混合方法设计将对88个受影响家庭和21个决策者的半结构化访谈与档案研究结合在一起。屡次发生的洪灾事件突显出，标准保护并不能满足所有河滨社区的需求。结果，国家当局充当了政策企业家，提倡有计划的搬迁和指导话语。相比之下，当地的利益相关者和居民起着消极的作用。搬迁政策从临时的非正式安排发展到正式的程序。迁移治理是在很长一段时间内随着增量更改而发展的，而不是立即，彻底的破坏。居民对政策的接受在很大程度上取决于社会学习以及与个人情况和传记阶段的吻合。政策窗口已经开放了数年，当时不断进行的公开辩论产生的预信号不断累积，而公共行政人员的决策制定了不同的时间表，当选代表和居民一致。关键因素是地方一级的长期视野，灵活性，参与度和社会能力，以处理和管理计划中的搬迁。