CRISP 2.0 Type 1: Interdependent Water Infrastructure in a Potable Reuse System

这项关键弹性相互依赖基础设施系统和过程（CRISP）研究的总体目标是描述洪水控制、废水和饮用水基础设施的相互依赖和弹性，特别是对卫生设施和管理不足的无庇护无家可归者营地对水质的影响。在美国，无家可归是影响人类健康、福祉和生态系统服务的最重要问题之一。这个问题在拉斯维加斯尤为明显，67%的无家可归者没有住所。这引起了人们对人类粪便污染当地水系统，特别是防洪基础设施对公众和环境健康的影响的关注。与美国许多城市类似，拉斯维加斯也将处理过的废水排放到饮用水入口的上游。因此，如果废水和饮用水基础设施没有足够的弹性，来自防洪基础设施的额外压力可能会形成一个正反馈循环，导致更多地暴露于新出现的关注的污染物和更频繁地爆发水传播疾病。这项研究的目标是取得与这些问题相关的两项长期成果：(1)生成可用于增进对无家可归问题对公共卫生更广泛影响的了解的数据和模型；(2)开发有效传播这方面知识的工具和产品，以促进采取更有效的措施解决无家可归问题并减轻对公共卫生和环境卫生的相关影响。虽然这项研究的重点是拉斯维加斯，但全国许多城市都存在与无家可归者和水质关系有关的问题，从而为其他地区提供了充分的复制机会。本研究采用跨学科的系统级方法来表征饮用水再利用背景下洪水控制、废水和饮用水基础设施的相互依赖性和复原力。这项研究的总体目标是充分描述无庇护的无家可归者营地的水质和公共卫生影响之间的关系。本研究涉及以下环境工程和社会科学假设。(1)没有住所的无家可归者缺乏卫生习惯，导致地表水水质严重恶化。使用先进的化学方法（气相色谱法/质谱法和液相色谱法/质谱法）对这些影响进行表征，以检测药物、非法药物和其他指示微量有机化合物。化学数据由先进的微生物学方法（16S rRNA基因测序、定量聚合酶链反应和微生物来源追踪）补充，用于检测粪便指标、人类特异性标记物和病原体。(2)防洪和污水基础设施增加了病原体和消毒副产物（DBP）前体负荷，可能导致饮用水基础设施系统对公众健康产生不利影响。病原体监测数据被整合到定量微生物风险评估（QMRA）框架中的系统动力学模型中。地表水、废水和防洪基础设施中DBP前体的相对贡献基于三卤甲烷（THM）、卤代乙酸（HAA）和亚硝胺形成电位，以游离氯、氯胺和臭氧为目标消毒剂。(3)臭氧-生物过滤的深度处理可以通过提高城市地区暴雨期间和暴雨后通常升高的n -亚硝基二甲胺（NDMA）的去除率来提高作为DBP屏障的饮用水基础设施的弹性。这一努力最好通过定量稳定同位素探测来确定负责NDMA生物降解的微生物分类群。研究小组还使用人种学方法来描述无家可归者的经历及其决策过程，从而允许开发有针对性的产出，从而为利益相关者和决策者提供信息。最后，通过与UNLV电影部门的合作，研究小组还制作了一部关于内华达州南部无家可归者和水质关系的短纪录片。除了让电影专业的学生了解工程和社会科学的现代问题外，这部纪录片还为未来旨在提高认识的宣传和教育活动奠定了基础。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。

The overall objective of this Critical Resilient Interdependent Infrastructure Systems and Processes (CRISP) research is to characterize the interdependence and resilience of flood control, wastewater, and drinking water infrastructure, and, in particular, the impact on water quality of unsheltered homeless encampments with insufficient sanitation facilities and management. Homelessness is one of the most significant issues affecting human health, well-being, and ecosystem services in the United States. The problem is particularly evident in Las Vegas where 67 percent of the homeless population is unsheltered. This raises concerns related to the public and environmental health implications of human fecal contamination of local water systems, specifically flood control infrastructure. Similar to many cities throughout the US, Las Vegas also discharges treated wastewater effluent upstream of its drinking water intakes. Therefore, if the wastewater and drinking water infrastructure are not sufficiently resilient, the added stress from flood control infrastructure may create a positive feedback loop leading to greater exposure to contaminants of emerging concern and more frequent outbreaks of waterborne disease. This research targets two long-term outcomes related to these issues: (1) generation of data and models that can be used to increase understanding of the broader public health implications of homelessness and (2) development of tools and products to effectively disseminate this knowledge to contribute to more effective measures to address homelessness and mitigate related impacts on public and environmental health. Although this research focuses on Las Vegas, concerns related to the nexus of homelessness and water quality exist in numerous cities throughout the country, thereby offering ample opportunity for replication in other regions.This research employs a transdisciplinary systems-level approach to characterize the interdependence and resilience of flood control, wastewater, and drinking water infrastructure in the context of potable reuse. The overall objective of the research is to fully characterize the nexus of water quality and public health implications of unsheltered homeless encampments. This research addresses the following environmental engineering and social science hypotheses. (1) Inadequate sanitation practices within the unsheltered homeless population result in significant deterioration of surface ater quality. These impacts are characterized using advanced chemical methods (gas chromatography/mass spectroscopy and liquid chromatography/mass spectroscopy) for the detection of pharmaceuticals, illicit drugs, and other indicator trace organic compounds. The chemical data are complemented by advanced microbiological methods [16S rRNA gene sequencing, quantitative polymerase chain reaction, and microbial source tracking] for the detection of fecal indicators, human-specific markers, and pathogens. (2) Flood control and wastewater infrastructure contribute pathogen and disinfection byproduct (DBP) precursor loadings that may lead to adverse public health impacts in drinking water infrastructure systems. Pathogen monitoring data are integrated into a system dynamics model in a quantitative microbial risk assessment (QMRA) framework. The relative contributions of DBP precursors from surface water, wastewater, and flood control infrastructure are based on trihalomethane (THM), haloacetic acid (HAA), and nitrosamine formation potentials using free chlorine, chloramines, and ozone as the target disinfectants. (3) Advanced treatment with ozone-biofiltration can be optimized to improve the resiliency of drinking water infrastructure as a DBP barrier by increasing the removal of N-nitrosodimethylamine (NDMA)which typically is elevated during and after rainstorms in urban areas. This effort is best informed by quantitative stable isotope probing to identify the microbial taxa responsible for NDMA biodegradation. The research team also uses ethnographic methods to characterize the homeless experience and their decision making processes, thereby allowing for the development of targeted outputs that can inform stakeholders and decision makers. Finally, through collaboration with the UNLV Department of Film, the research team also produces a short documentary on the nexus of homelessness and water quality in Southern Nevada. In addition to exposing film students to modern issues in engineering and social science, the documentary serves as the foundation of future outreach and education activities aimed at raising awareness.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.