By Kaycie Lane, PhD, Emily Kumpel, PhD and Kim Redden, MPH
The intent of the Safe Drinking Water Act (SDWA) allowing POU and POE water treatment was to help small systems achieve compliance.[1] It is curious that more small systems do not take advantage of this option. The reasons for compliance issues at these small systems are complex, which makes a timely solution challenging to navigate, as each system’s needs and resources are different. It could be upgrades needed at the treatment plant or repairs to the distribution system, including hiring the appropriate professionals to oversee the technical and engineering work. Small systems serve 3,300 people or less (and very small systems serve 25-500 people) so there are not as many customers to distribute the financial obligation as with larger systems. Loans or grants or other additional sources of financial means might be a barrier for small systems to make the needed improvements when compared to larger systems.[3] The interaction of all of these complex issues results in a delay to achieving compliance while new contaminant regulations continue to emerge. This begs the question, “What is the most sustainable solution long-term?”
WQRF-funded Sustainability Comparison Study
To address this novel sustainability question, WQRF is currently funding a project by the University of Massachusetts-Amherst, led by Drs. Kaycie Lane, Emily Kumpel, David Reckhow and John Tobiason. The hypothesis is that at some threshold of factors in small systems, it may be more sustainable (with respect to the human, economic and environmental impacts) to use POU/POE rather than to upgrade a centralized treatment plant or consolidate with another PWS. The researchers will test this hypothesis through exposure assessment and cost modeling as well as a life-cycle assessment for case studies in small communities across the United States. The researchers have identified four small public water system (PWS) case studies with an SDWA violation for either arsenic or nitrate. The names of the PWSs will be kept anonymous but the US EPA region, contaminant and population served will be available for reference.
The triple-bottom line analysis includes the human health risks and economic and environmental impacts for both POU/POE and centralized treatment upgrades to help very small systems achieve regulatory compliance. The human health risks evaluates the time it takes the system to achieve compliance, to investigate which strategy helps the PWS reduce the time of potential exposure to a contaminant. The economic costs will be calculated using a life -cycle costing approach for the entire process, from construction to long-term maintenance. The environmental impacts will be estimated through a hybrid LCA process utilizing an economic input-output model approach. All three factors will be modeled and analyzed to compare the POU/POE and centralized treatment upgrade option for each case study. Additional results from this research, beyond the case study communities, will provide an answer to the following question for small systems, “At what point is POU/POE the more sustainable option and at what point would centralized upgrades be more sustainable?”
What factors play into this? Is it just the number of people served/connections or is there another factor to consider that will help guide small PWS in the future towards achieving compliance? The researchers have collected data from the case study communities. They are in the process of selecting options for and modeling the costs of POU/POE devices that would be viable in the case study communities to compare to the upgrades that would be necessary to the existing centralized system. The researchers have presented the scope of their project at the US EPA Small Systems Workshop in 2020 for awareness and involvement of the small systems, and the research is anticipated to complete in spring of 2022.
Other research to address potential barriers
Despite what appears to be robust guidance from US EPA and technology certification standards, there seem to be other reasons that POU/POE is not more widely utilized as a compliance strategy. US EPA has published guidance for small systems seeking to implement POU/POE, including comprehensive tools for cost estimations of equipment and on-going labor and maintenance that any PWS can use to evaluate what is best for their specific community. The federal statute allowing use of POU or POE, however, does not automatically mean states have a process for approval. The PWS must obtain approval from the state for the monitoring plan, performance, field-testing and engineering design review of the POU/POE devices. Additionally, US EPA guidance states that if an ANSI certification standard exists for the technology and contaminant, then the PWS must use a certified device. If , however, an ANSI standard does not exist for the technology/device, then “States should utilize manufacturers’ substantiations of products’ performances, results from pilot tests conducted by other systems or applications, and on-site testing by the system.”[1]
US EPA guidance includes charts that easily clarify the POU/POE technologies that can be used for which contaminants. Most ANSI-accredited certification bodies have online searches to find products for the technology and contaminant combinations that have certification standards that apply. Overall, it seems the guidance is available for what devices can be used but perhaps the approval processes at the state level may be an area where more research or guidance is needed.
Another future WQRF-funded research project is a survey to gather feedback from all states and develop a comprehensive database of POU/POE for compliance. The survey will dig a little deeper than other surveys conducted in the past by gathering specific information on the states’ approval process and communities currently using POU/POE. If the state doesn’t allow POU/POE, the survey will identify barriers to POU/POE devices as a compliance strategy and what is needed to overcome those barriers. The WQRF research task force is currently vetting proposals and the research is anticipated to begin by summer 2021.
Another potential barrier that has been discussed anecdotally is that the PWS customers won’t be receptive to the idea of home water treatment or allowing professionals into their homes. According to the 2021 WQA Consumer Opinion Study, 58 percent of respondents surveyed indicated that they’d be willing to have water treatment in their home if they were not responsible for maintaining it other than letting someone in their home to service it. This increased to 61 percent of respondents when asked the same question with the responsibility for maintaining the system being their city water provider.[4] This data is the first glimpse into the public acceptance of using POU/POE for compliance and shows promise that there is already public awareness of POU/POE as a solution.
Sources
1. USEPA. (2006) Point-of-use or point-of-entry treatment options for small drinking water systems. United States Environmental Protection Agency. Retrieved from: https://www.epa.gov/sites/production/files/2015-09/documents/guide_smallsystems_pou-poe_june6-2006.pdf
2. USEPA. (2007) Cost evaluation of point-of-use and point-of-entry treatment units for small systems: cost estimating tool and user guide. United States Environmental Protection Agency. Retrieved from: https://www.epa.gov/sites/production/files/2015-04/documents/epa815b07001.pdf
3. Allaire, Maura et al. (2018) National trends in drinking water quality violations. Proceedings of the National Academy of Sciences of the United States of America. Retrieved from: https://www.pnas.org/content/115/9/2078
4. Applied Research West-Inc. (2021) National study of consumers’ opinions and perceptions regarding water quality. Water Quality Association. Unpublished data.
About the authors
Kaycie Lane is a Postdoctoral Scholar at the University of Massachusetts Amherst. She obtained her PhD in 2020 from Dalhousie University, Nova Scotia, Canada and holds a BSc in engineering physics from Colorado School of Mines. Lane’s research focuses on risk management for small water systems and she is currently exploring the use of POU and POE devices for very small drinking water systems in the United States.
Dr. Emily Kumpel is an Assistant Professor in the Department of Civil and Environmental Engineering at University of Massachusetts Amherst. She has an MS Degree and PhD in civil and environmental engineering from the University of California, Berkeley, and was previously a Senior Research Scientist with the Aquaya Institute in Nairobi, Kenya.
Kimberly Redden has worked for the Water Quality Association (WQA) in the Technical and Regulatory Affairs Department and the Professional Certification and Training Department. She now serves in the role of Foundation Relations and Research Manager for the Water Quality Research Foundation (WQRF). Redden has a Bachelor’s Degree in chemistry from North Central College and a Masters of Public Health from Elmhurst College.