Collaborative Research: Urban Watershed Evolution - Novel Temporal Perspectives on the Hydrologic Impacts and Positive Unintended Consequences of Failing Municipal Infrastructure

合作研究：城市流域演化——关于水文影响和市政基础设施故障的积极意外后果的新的时间视角

• 批准号: 2055491
• 负责人: Bryan Black
• 金额: $ 6.9万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-15 至 2024-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2055491&HistoricalAwards=false
• 关键词: Collaborative; Research; Urban; Watershed; Evolution

Municipalities are increasingly challenged to use aged and failing infrastructure to deliver a continuous supply of clean water, and to return and treat wastewater, yet little is known about when, where, and how infrastructure failures were initiated or how they progressed. This project has three main scientific goals including: 1) determining the fate of municipal water after it leaves the engineered system and enters the natural hydrologic system, 2) unravel when, and under what conditions, infrastructure failure began, and 3) understanding how this failure and its impacts on water resources have progressed over time. The primary project activities comprise using naturally-occurring chemical tracers in stream water and trees to reconstruct a history of water quality, and using historical data to reconstruct a history of infrastructure development. We expect our approach will be transferrable to other urban systems with aging infrastructure. Most broadly, this project will leverage our network of stakeholders to help inform city-level planning efforts to implement resilient infrastructure while accommodating rapid expansion of urban populations in the 21st century. Results from this project will be incorporated across the sustainability curriculum at the University of Texas at Austin, which includes interdisciplinary degrees and 24 courses that emphasize field experiences and engage 800 students per year in on-campus environmental research along one of the proposed stream study sites, as well as geoscience graduate programs at UT Austin and the University of Arizona. Graduate and undergraduate student training will emphasize inclusion of underrepresented minorities.At the onset of infrastructure failure in each Austin watershed, municipal water was introduced by leakage into relatively pristine natural hydrologic systems. We hypothesize that the distinct chemical compositions of these anthropogenic water sources were recorded in bald cypress trees at the onset of failure and in subsequent years as failure progressed. This project comprises a novel application of natural isotopic tracers to examine the impacts of urbanization on natural hydrology and stream ecology in three watersheds in the same hydrogeologic terrain. The primary variable among the watersheds is the extent of urbanization. We will analyze elemental, and Sr isotope variations in stream water, and develop methods for high resolution measurements of the Sr isotopes in the growth rings of bald cypress trees growing adjacent to those streams. We posit that the growth rate and isotopic composition of the tree rings encode a hydrologic history of the progressive failure of infrastructure. We will apply these data using hydrogeochemical models to: 1) trace the evolution of municipal water during its transmission through the natural hydrologic cycle in anthropogenically compromised watersheds; and 2) use dendrochemical variations to reconstruct decadally-resolved temporal changes in municipal water input to streams. These results will be used to identify, for the first time, both the timing of the onset of infrastructure failure and temporal changes in the magnitude and impacts of the failure. We will compare this temporal record of municipal water input with the history of urban development in the same watersheds to determine the threshold for the extent of urbanization, above which hydrologic and ecological impacts of failing infrastructure are manifested. This award is co-funded by the Hydrologic Sciences, Environmental Sustainability, and Environmental Engineering programs.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.

市政当局越来越挑战使用老化和失败的基础设施来提供持续的清洁水供应，并返回和处理废水，但是对于何时，何时何地，何处以及如何启动基础设施失败或如何进步，几乎不知道。该项目具有三个主要的科学目标，包括：1）确定市政水离开工程系统并进入自然水文系统后的命运，2）何时以及在什么条件下开始，基础设施失败开始，以及3）了解这种失败及其对水资源的影响如何随着时间的推移而进展。主要的项目活动包括在溪流和树木中使用自然出现的化学示踪剂来重建水质史，并使用历史数据来重建基础设施发展的历史。我们预计我们的方法将可以转移到具有老化基础设施的其他城市系统。最广泛的是，该项目将利用我们的利益相关者网络来帮助城市级别的规划工作，以实施弹性基础设施，同时适应21世纪的城市人口的快速扩张。该项目的结果将在德克萨斯大学奥斯汀分校的整个可持续性课程中纳入，其中包括跨学科学位和24个课程，这些课程强调野外体验，并与拟议中的流媒体研究网站之一的校园内环境研究以及在奥斯汀大学和Arizone大学的地球科学研究生课程进行校园环境研究。毕业生和本科生培训将强调包括代表性不足的少数民族。在每个奥斯汀流域的基础设施失败时，通过泄漏到相对原始的自然水文系统中引入了市政水。我们假设这些人为水源的独特化学成分在失败开始时在秃头树中记录在秃头树中，随着失败的进展。该项目包括自然同位素示踪剂的新应用，以检查城市化对自然水文和溪流生态学在同一水文地质地形中的三个流域的影响。流域中的主要变量是城市化的程度。我们将分析流水中的元素和SR同位素变化，并开发用于高分辨率测量的方法，以高分辨率测量与这些流相邻的秃头柏树生长环的生长环。我们认为，树环的生长速率和同位素组成编码基础设施进行性失败的水文历史。我们将使用水力地球化学模型应用这些数据以：1）在人为损害的流域中，通过自然水文循环传播市政水在其传播过程中的演变；和2）使用树状化学变化来重建市政水输入到溪流中的十年时间变化。这些结果将首次用于识别基础设施故障发作的时机和失败的大小和影响的时间变化。我们将将这种市政水的投入的时间记录与同一流域中城市发展的历史进行比较，以确定城市化程度的阈值，而基础设施失败的水文和生态影响在此上面表现出来。该奖项由水文科学，环境可持续性和环境工程计划共同资助。该奖项反映了NSF的法定任务，并且使用基金会的知识分子优点和更广泛的影响审查标准，认为值得通过评估来获得支持。