CAREER: Turning Home Water Storage from Risk into Reliability

The three pillars of a safely managed water supply under the United Nations Sustainable Development goals are that water is free of contamination, located on-premises, and available when needed. For billions of people throughout the world, water is delivered, pumped, or precipitated intermittently into structure-level water storage, with the storage then enabling the water supply to be on-premises and available when needed.

With increasing outages to water supplies due to aging infrastructure and/or climate change induced extreme weather events such drought or flooding, household or building water storage has become an essential component of premise plumbing systems. Despite the important role of storage in household/building water supply, there are critical challenges in maintaining safe water through storage as many studies have established that microbial water quality degrades between distribution system mains or source water and storage, evidenced by higher concentrations of indicator bacteria or pathogens.

This degradation of the quality of stored water is often associated with water age (the time water spends in distribution or plumbing system infrastructure) and the accompanying loss of disinfectant residual and elevated temperatures that foster microbial growth. The overarching goal of this CAREER project is to test the hypothesis that local water storage can be designed to preserve or even improve water quality following contamination events while achieving resiliency through interruptions.

The successful completion of this project will benefit society through the generation of new fundamental knowledge about microbial persistence and growth in water storage systems while providing valuable insight into the efficacy of interventions to improve stored water quality. Additional benefits to society will be achieved through student education and training including the mentoring of one post-doctoral research fellow, one graduate student, and one undergraduate student at the University of Massachusetts Amherst.

Local household/building cold water storage is an essential yet often neglected component of premise plumbing systems. This CAREER project will advance the fundamental understanding of the dynamics of water quality while it is in storage with the goal of enabling the design of premise plumbing systems that are resilient in the face of water supply interruptions while maintaining the integrity of water quality.

The specific objectives of this research are to: 1) Quantify the effects of a contamination event on the accumulation, persistence, and release of indicator bacteria and opportunistic pathogens in home water storage tanks that are supplied with municipal tap water; 2) Investigate the efficacy of interventions to minimize microbial persistence and growth in home water storage while minimizing water consumption, supply interruption, and cost; and 3) Develop a framework for optimizing water storage volumes to meet water safety, supply, and reliability goals. By integrating experiments and modeling, the Principal Investigator (PI) hopes to uncover the critical design and operational parameters that control the tradeoffs between water quality and water storage capacity in household and building premise plumbing systems.

To implement the educational goals of this CAREER project, the PI proposes to leverage existing programs and resources at the University of Massachusetts Amherst to advance the development and implementation of a new pedagogy to train students in use-inspired design thinking to facilitate innovation in water systems. The proposed educational and outreach activities will include 1) the organization of a hands-on design competition, adapted for K-12 through undergraduate student levels, that challenges students to brainstorm and design resilient home water storage systems; 2) the design and implementation of a new graduate course on intermittent water delivery and home water storage; and 3) the design and implementation of a water supply outage monitoring map accessible to the public that will track outages across the United States.

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.