Sustainable Stormwater Management Approach: Optimal Implementation of Low Impact Development Systems

2003年至2012年间，加拿大的城市洪水造成了超过200亿美元的损失，尽管在过去几十年里，加拿大在雨水最佳管理实践方面进行了大量的公共投资。最常用的管理实践主要是管道末端基础设施，旨在通过将雨水径流输送到最近的接收水体，将雨水径流从建筑环境中转移出去。最近，低影响发展（LID）技术（如生物威尔士、雨水花园、绿色屋顶和透水路面）在加拿大许多城市得到了普及和采用。LID实践的目的是管理靠近源头的径流，模仿自然或开发前的水文过程，如渗透和滞留。然而，主要由于缺乏可靠的观测数据和这些做法的分散性，它们的长期功能、性能、维护、放置以及它们对大规模流域雨水管理的集体影响仍然存在不确定性。有了强大而有效的雨水管理模型，降雨数据系列的可用性以及数据分析工具的进步，就有机会填补这一空白。总体目标是开发一个框架，帮助在气候变化和城市快速发展的情况下，在加拿大城市地区实施可持续雨水管理（LID）。短期目标是1)开发一套新的可靠的分析概率径流数量和质量模型和LID模块，2)评估与已开发模型和气候变化相关的不确定性，以及3)创建一个全面有效的框架，在社区一级最佳实施LID系统，包括已开发的雨水管理模型。不确定性量化模式与气候变化、邻域和LID特征。长期目标是将该框架扩展到流域一级，纳入加拿大以生态系统为重点的倡议。由此产生的知识将提高我们对雨水管理系统的性能和维护的理解。它还将确保加拿大社区在极端降雨事件、气候变化和城市增长下的弹性和可持续性。这一研究项目将有助于培养雨水管理、数据分析和建模技术方面的高素质人才。所提出的模型和工具将促进针对加拿大城市的最佳、高效和弹性LID实践的实施，以减少城市径流的影响，防止数十亿美元的损失。

Urban flooding in Canada accounted for more than $20 billion in damage between 2003 and 2012, despite the massive public investment in stormwater best management practices over the last decades. The most used management practices are mainly end-of-pipe infrastructures, aiming to divert stormwater runoff away from the built environment by delivering it to the nearest receiving waterbody. Recently, low-impact-development (LID) technologies (e.g., bioswales, rain gardens, green roofs and permeable pavement) have gained popularity and adopted by many Canadian cities. LID practices aim to manage runoff close to its source, mimicking natural or predevelopment hydrological processes such as infiltration and retention. However, mainly due to the scarcity of reliable observed data and the decentralized nature of these practices, there remains uncertainty as to their long-term functionality, performance, maintenance, placement, and their collective impact on large-scale watershed stormwater management. With robust and efficient stormwater management models, availability of rainfall data series and advances in data analysis tools, there is an opportunity to fill this gap. The overarching objective is to develop a framework that can assist in implementing sustainable stormwater management (LID) in Canadian urban areas under climate change and rapid urban development. The short-term objectives are to 1) develop a new set of reliable analytical probabilistic runoff quantity and quality models and LID modules, 2) assess the uncertainties associated with the developed models and climate change, and 3) create a comprehensive and efficient framework for optimal implementation LID systems at a neighbourhood level, incorporating the developed stormwater management models, uncertainty quantification models and climate change and neighbourhood and LID characteristics. The long-term objective is to extend the framework for the watershed level, incorporating Canada's ecosystem-focused initiatives. The generated knowledge will improve our understanding of the performance and maintenance of stormwater management systems. It will also ensure the resilience and sustainability of Canadian communities under extreme rainfall events, climate change and urban growth for generations to come. This research program will help train highly qualified personnel in stormwater management, data analysis and modelling techniques. The proposed models and tools will facilitate the implementation of optimal, efficient and resilient LID practices geared towards Canadian cities to lessen urban runoff impacts and prevent billions of dollars in damages.