Abstract A plethora of socioenvironmental issues, and growing concerns over the effects of climate change, are forcing cities to rethink conventional urban water management practices. However, change towards more sustainable practices has been remarkably slow. This paper examines two cases of greening projects aimed at urban rehabilitation in Stockholm and Barcelona, which have turned into examples of innovative approaches to urban rain management. Both cities share high densities and flooding problems in certain neighborhoods. Specifically, the paper attempts to answer three questions: 1) what were the driving forces and key factors that facilitated the breakthrough of urban rainwater-harvesting (URH) schemes based on the two cases?; 2) who were the actors involved and what were their roles in moving towards URH schemes?; and 3) how can URH schemes become part of multifunctional, sustainable urban systems? To answer these questions, the paper uses concepts of adaptive context and capacity, and of actor agency, drawn from the transitions literature, and opportunistic and guided flexibility planning drawn from the planning literature. Empirical material for both case studies was obtained from policy documents and semi-structured interviews with key actors. The main results show first political support for flexibility in public planning, the adaptive context and the capacity of the actors, especially in taking advantage of windows of opportunity for the materialisation of new ideas. Second, the design and implementation of these systems widened the number and scope of actors in urban water management, incorporating new professionals such as architects and involving more city agencies and organizations. Third, small scale URH systems contributed not only to control urban drainage but performed other functions such as the much-needed greening of dense areas in both cities.

中文翻译：

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通过城市绿化规划实现城市雨水收集计划的突破：斯德哥尔摩和巴塞罗那的案例研究

摘要 过多的社会环境问题，以及对气候变化影响的日益关注，迫使城市重新思考传统的城市水资源管理实践。然而，向更可持续的做法转变的速度非常缓慢。本文考察了斯德哥尔摩和巴塞罗那的两个旨在城市修复的绿化项目案例，它们已成为城市雨水管理创新方法的例子。这两个城市在某些社区都存在高密度和洪水问题。具体而言，本文试图回答三个问题：1）基于这两个案例，推动城市雨水收集（URH）方案取得突破的驱动力和关键因素是什么？2) 谁是参与者，他们在推进 URH 计划方面扮演什么角色？3) URH 计划如何成为多功能、可持续城市系统的一部分？为了回答这些问题，本文使用了从转型文献中提取的适应性环境和能力以及行动者代理的概念，以及从规划文献中提取的机会主义和引导式灵活性规划。两个案例研究的实证材料均来自政策文件和对关键参与者的半结构化访谈。主要结果首先显示了对公共规划灵活性、适应性环境和参与者能力的政治支持，特别是在利用机会窗口实现新想法方面。其次，这些系统的设计和实施扩大了城市水管理参与者的数量和范围，吸收新的专业人士，如建筑师，并让更多的城市机构和组织参与进来。第三，小规模的URH系统不仅有助于控制城市排水，还发挥了其他功能，例如两个城市急需的密集地区绿化。