This NSF Engineering Research Initiation project will develop a novel hybrid centralized and decentralized water system (water microgrid system) to achieve both water supply sustainability and resilience. Current centralized water infrastructure faces enormous challenges from climate change, extreme drought, population growth, ageing infrastructure, and energy security. Such challenges require a transformation of current water systems to be more sustainable and resilient. This project establishes benchmark models of a water microgrid system, which features decentralized water supply systems with local water sources nested within existing centralized systems. The water microgrid system will increase water use efficiency and conservation through water recycling and harvesting for distributed water sources. Furthermore, the system can change its operations between centralized and decentralized water supply against unexpected disruptions and thus will enhance system resilience. The project outcomes will advance scientific progress by providing the practice of the Law of Requisite Variety. They will contribute to national welfare and water services by suggesting engineering solutions to upgrade current water infrastructures to make them more sustainable and resilient. The project team will conduct integrated education and outreach activities through water forms, a project website, publications, course development, international partnerships, and other outreach programs for the public and K-12 students. This project will encourage the participation of underrepresented students in research activities. 

This project aims to advance the understanding of a hybrid microgrid approach for water systems and its sustainability and resilience outcomes. The project will contribute to knowledge on how to incorporate decentralized infrastructure in tandem with current centralized water systems for water supply sustainability and resilience. The project tasks include (1) building a lab-scale physical model of a water microgrid system; (2) testing the configuration and operations of a water microgrid system using a hydraulic model; (3) developing a framework to sectorize an existing water supply system into microgrids; and (4) evaluating the sustainability and resilience effects of water microgrid systems based on system size, decentralization levels, and failure scales. The project outcomes will provide insights and guidance to facilitate a transition from current urban water infrastructure to new ways of simultaneously improving water sustainability and system resilience. These outcomes will also lead to new planning, design, and tools for urban lifeline infrastructure to effectively incorporate microgrid and decentralized infrastructure.