Collaborative Research: Reimagining Urban Watershed Management: A Systems Approach to Stormwater Control and Ecological Rehabilitation

预计越来越多的更大、更密集的城市将对全世界的河流生态系统产生更大、更普遍的压力。城市化导致更多的雨水径流，这可能导致一系列生态损害，这些损害被统称为“城市河流综合症”（USS）。因此，雨水控制是保护和恢复城市水道的核心，但雨水管理在很大程度上优先考虑社会关注的目标，如防洪和保护基础设施，而不是考虑接收水的生态功能。因此，在“解决综合症”方面几乎没有取得进展。该项目旨在通过设计和展示一种系统方法来改变城市径流的管理方式，以恢复河流内的生态条件。期望这项工作将产生基本的技术和概念进步，以实现急需的下一代雨水基础设施，解决国家工程院提出的恢复和改善城市基础设施的重大挑战。该项目可以大大改善美国和其他国家的地表水状况。根据美国环保署的数据，城市径流可能是美国49,000多英里河流和溪流受损的来源，这个惊人的数字说明了创新雨水管理解决方案的潜在影响。该项目的目标是通过创建恢复和保护地表水的新框架，为改变城市径流管理方式提供基础。该项目将雨水径流重新定义为一个环境流动问题，可以通过将传统的雨水基础设施升级为能够自适应地满足生态和监管目标的网络物理“智能雨水”系统来解决。用绿色替代方案（如生物湿地、湿池）静态和分散地替代灰色雨水基础设施并没有提供USS的纠正措施。这导致越来越多的人倡导将业务转向流域尺度的雨水干预协调，并从环境流动的角度看待城市雨水管理的概念转变。传感器和控制系统的最新进展使得雨水基础设施可以作为一个“智能”系统来管理径流如何以及何时排放到接收流中，这为基于一系列多重目标（重新）建立所需的流量机制提供了前所未有的机会。在这个项目中，目标是确定和演示如何调整雨水系统，以实现环境流动作为一个目标功能，以满足生态和监管目标。该项目将模型参数化和模拟与经验测试相结合，目的是评估是否有可能使用“智能雨水”方法实现环境流动(1)；(2)改变城市河流的生态系统属性和功能；如果是，则(3)减轻了USS特有的损伤。这将需要(1)确定和确定城市流域的生态知情绩效目标；(2)利用系统方法优化雨水干预措施，利用可控制的出口和自适应控制算法；(3)在两个试验平台上对站点级和系统级智能雨水管理进行了实证论证和评估。该项目还将通过教育合作伙伴关系进行公共宣传。项目团队将继续与田纳西州的诺克斯县学校合作，举办两年一次的“与河流相遇”公民科学活动，为学生提供机会，了解城市化对河流的影响和雨水控制自动化，并收集有关河流条件的物理和生物数据，以支持K-12课程目标。此外，这项研究的各个方面将被纳入研究者在各自机构教授的专题课程，包括生态恢复研究生研讨会和以建模和分析为重点的工程课程。该项目将通过UTK工程多样性项目办公室等组织招募来自代表性不足群体的学生，帮助促进STEM领域的多样性、公平性和包容性，并为研究生教育和职业发展提供良好的机会。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

It is expected that a greater number of larger and denser cities will manifest more potent and pervasive pressures on stream ecosystems worldwide. Urbanization leads to greater stormwater runoff, which can result in a slate of ecological impairments that collectively have been identified as the “urban stream syndrome” (USS). Stormwater control is thus central to protecting and rehabilitating urban waterways, but stormwater management has largely prioritized objectives motivated by societal concerns, like flood control and protecting infrastructure, over consideration of ecological functions in receiving waters. Consequently, little progress has made towards ‘solving the syndrome’. This project aims to transform how urban runoff is managed by designing and demonstrating a systems approach to upland interventions to rehabilitate in-stream ecological conditions. The expectation is that the work will yield fundamental technological and conceptual advances to realize much-needed next generation stormwater infrastructure, addressing the grand challenge laid out by the National Academy of Engineering to Restore and Improve Urban Infrastructure. The project could substantively improve the condition of surface waters across the US and abroad. According to the US EPA, urban runoff is the probable source of impairment for over 49,000 miles of rivers and streams that have been assessed in the US, a staggering number that illustrates the potential impact of innovative stormwater management solutions. It is the goal of the project to provide the foundation for transforming how urban runoff is managed by creating a new framework for rehabilitating and protecting surface waters. The project will recast stormwater runoff as an environmental flows problem that can be addressed by upgrading traditional stormwater infrastructure into cyber-physical ‘smart stormwater’ systems capable of adaptively meeting ecological and regulatory objectives.Static and decentralized replacement of grey stormwater infrastructure with green alternatives (e.g., bioswales, wet ponds) has not provided corrective remedies of USS. This has led to increasing advocacy for operational shifts towards basin-scale coordination of stormwater interventions and conceptual shifts towards viewing urban stormwater management through the lens of environmental flows. Recent advances in sensors and controls now allow stormwater infrastructure to be operated as a ‘smart’ system for managing how and when runoff is discharged into a receiving stream, affording unprecedented opportunities to (re)establish desired flow regimes based on a set of multiple objectives. In this project, the target is to determine and demonstrate how stormwater systems can be tuned to achieve environmental flows as an objective function to meet ecological and regulatory goals. The project will combine model parameterization and simulations with empirical tests, with the aim of assessing whether achieving environmental flows (1) is possible using a ‘smart stormwater’ approach; (2) alters ecosystem attributes and functioning in urban streams; and if so, (3) alleviates impairments characteristic of USS. This will entail (1) identifying and defining ecologically-informed performance objectives for urban watersheds; (2) using a systems approach to optimize stormwater interventions that leverage controllable outlets and adaptive control algorithms; and (3) empirically demonstrating and evaluating site- and system-level smart stormwater management at two experimental testbeds. The project also will also pursue public outreach through educational partnerships. The project team will continue to work with Tennessee's Knox County Schools to host biannual “Meet the Creek” citizen science events that offer students opportunities to learn about the effects of urbanization on streams and automation of storm water control, as well as collect physical and biological data on in-stream conditions that will support K-12 curricular goals. Additionally, aspects of this study will be integrated into topical courses taught by the investigators at their respective institutions, including a graduate seminar on ecological restoration and engineering courses focusing on modeling and analytics. The project will help advance diversity, equity and inclusion in STEM fields by involving students from underrepresented groups, who will be recruited through organizations like the UTK Engineering Office of Diversity Programs, and will afford excellent opportunities for graduate education and career advancement.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.