CAREER: Elucidating hydrodynamic drivers of microbial water quality in drinking water distribution systems

饮用水分配系统（DWDS）是通过确保饮用水从处理厂到消费点的安全来保护公众健康的关键基础设施。然而，饮用水在流经DWDS广泛的管道网络时，其质量可能会下降。生物膜在配水管表面上的生长是一个特别关注的问题，因为它以各种方式对水质有害，包括通过创建能够窝藏病原微生物的保护性环境，加速消毒剂残留物的腐烂，促进消毒副产物的形成，以及释放引起味道、气味和水变色问题的化合物。然而，管道流体力学，生物膜性能，和水质之间的关系，在DWDS的基本理解仍然难以捉摸。这个CAREER项目的总体目标是推进水动力学条件对饮用水管道表面形成的生物膜的组成，结构和稳定性的影响的基本理解。该项目的成功完成将使社会受益，通过发展基本知识来指导DWDS的管理，目标是提高消费点饮用水的质量和安全。通过学生教育和培训，包括指导西弗吉尼亚大学的一名研究生和两名本科生，将为社会带来额外的好处。饮用水管道表面生物膜的形成和生长对饮用水分配系统（DWDS）的水质和安全有重大影响。配水管的生物膜的结构和组成在调节饮用水的质量方面起着关键作用。这些生物膜的基本理解，包括其结构，组成，稳定性，病原体附着/释放的倾向，并有可能诱导/催化消毒副产品的形成过程中，通过氯化或臭氧化的水消毒的影响，昼夜波动的流体动力学条件下，有关键的知识差距。这个职业生涯项目将解决这些知识差距。本研究的具体目的是：1）评估DWDS中生物膜的物理特性和相关的病原体附着和分离对水流剪切力重复变化的响应; 2）评估水动力变化对生物膜中胞外聚合物的数量/组成的影响以及对水质的相关影响;研究了不同水力条件对DWDS中沉积物表面生物膜形成的影响。这项研究的成功完成具有潜在的变革性影响，通过结合受控的实验室规模实验，对饮用水管道中的生物膜进行机械理解，分析从全规模饮用水分配系统收集的样本，并建模以基准和验证研究结果。为了实现这个职业项目的教育和培训目标，首席研究员（PI）建议在西弗吉尼亚大学开发一门新的本科课程，重点是分散式污水处理技术。此外，PI计划开发和提供一个教育模块，题为“为什么水在农村社区的事项”，从西弗吉尼亚州农村社区的K-12学生，提高水的职业意识的目标，促进招聘年轻专业人员到当地的水和废水学徒计划，并促进人们对水在支持健康和繁荣社区方面所发挥的重要作用的认识。该项目由CBET环境工程项目和既定项目联合资助激励竞争性研究计划（EPSCoR）。该奖项反映了NSF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。

Drinking water distribution systems (DWDS) are critical infrastructure that protect public health by ensuring the safety of drinking water as it travels from treatment plants to points of consumption. However, the quality of drinking water can degrade as it flows through the extensive pipe networks of DWDS. Growth of biofilms on the surfaces of water distribution pipes is a particular concern as it is detrimental to water quality in various ways, including by creating a protective environment capable of harboring pathogenic microorganisms, accelerating the decay of disinfectant residual, facilitating the formation of disinfection byproducts, and the release of compounds that cause problems with taste, odor, and water discoloration. However, a fundamental understanding of the relationships between pipe hydrodynamics, biofilm properties, and water quality in DWDS has remained elusive. The overarching goal of this CAREER project is to advance the fundamental understanding of the impact of hydrodynamics conditions on the composition, structure, and stability of biofilms that form on the surfaces of drinking water pipes. The successful completion of this project will benefit society though the development of fundamental knowledge to guide the management of DWDS with the goal of improving both the quality and safety of drinking water at the points of consumption. Additional benefits to society will be achieved through student education and training including mentoring of one graduate and two undergraduate students at West Virginia University.The formation and growth of biofilms on the surfaces of drinking water pipes have a major impact on water quality and safety in drinking water distribution systems (DWDS). The structure and composition of the biofilms of water distribution pipes play a key role in modulating the quality of drinking water at the points of consumption. There are critical knowledge gaps in the fundamental understanding of these biofilms including the impact of diurnal fluctuations in hydrodynamic conditions on their structure, composition, stability, propensity for pathogen attachment/release, and potential to induce/catalyze the formation of disinfection by-products during water disinfection by chlorination or ozonation. This CAREER project will address these knowledge gaps. The specific objectives of the proposed research are to: 1) evaluate biofilm physical characteristics and associated attachment and detachment of pathogens in DWDS in response to repeated variations in shear stress during water flow; 2) assess the impact of variations in hydrodynamic forces on the amount/composition of extracellular polymeric substances in biofilms and associated impacts to water quality; and 3) investigate the effect of variable hydraulic conditions on the formation of biofilms on sediment surfaces in DWDS. The successful completion of this research has the potential for transformative impact by combining controlled bench-scale experiments to develop a mechanistic understanding of biofilms in drinking water pipes with the analysis of samples collected from a full-scale drinking water distribution system, and modeling to benchmark and validate the research findings. To implement the educational and training goals of this CAREER project, the Principal Investigator (PI) proposes to develop a new undergraduate course at West Virginia University that will focus on decentralized wastewater treatment technologies. In addition, the PI plans to develop and deliver an education module entitled “Why Water Matters in Rural Communities” to K-12 students from rural communities in West Virginia with the goals of increasing awareness of water careers, promoting the recruitment of young professionals into local water and wastewater apprenticeship programs, and advancing the recognition of the essential role that water plays in supporting healthy and prosperous communities.This project is jointly funded by the CBET Environmental Engineering program and the Established Program to Stimulate Competitive Research (EPSCoR).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.