Grant Awarded for Study of Climate-Induced Septic Tank Failures

Thousands of residents of rural and coastal areas face a potential sanitation crisis as rising sea levels put a strain on aging septic tank systems, according to a University of Maryland (UMD) researcher who is leading an Environmental Protection Agency-funded (EPA) study of the problem.

The EPA this week announced that it is awarding $1,350,000 in support for the project, headed up by UMD civil and environmental engineering faculty member Allison Reilly and including researchers from the UMD College of Engineering, the UMD School of Public Health, the UMD College of Agriculture and Natural Resources, and George Mason University, as well as the research institution Resources for the Future and the water-justice non-profit Southeast Rural Community Assistance Project, Inc. (SERCAP). The grant is part of the EPA’s Cumulative Health Impacts at the Intersection of Climate Change, Environmental Justice, and Vulnerable Populations/Life Stages: Community-Based Research for Solutions funding opportunity.

More than 52,000 homes in Maryland rely on septic and are within 1,000 feet of tidally-influenced water. Rising sea water creates hydrostatic pressures that can cause septic tanks to fail, and the saturated soil impedes nutrients and presents opportunities for exposure to disease-causing pathogens, Reilly explained.

Photo credit: Aleem Waris

Furthermore, she said, it can increase the risk of nitrogen and phosphorus loads seeping into area waterways. In addition, the warmer temperatures of the oceans will cause more frequent and stronger hurricanes, forcing more surge water onto shore. Not only is this mix of interrelated phenomena troubling from an environmental perspective, but it exacerbates existing racial and socioeconomic disparities.

“There’s an environmental issue, because failing septic tanks can contaminate water resources, but it’s also an environmental justice issue,” Reilly said. “Historically, Black communities are more likely to rely on septic systems rather than on sewer systems, in part because of past racist perceptions about ability-to-pay and ‘deservedness’ for municipal sewer infrastructure. Compounding this, communities of color are disproportionately more exposed to sea-level rise and flooding, due to racist housing and land-use policies. And troubling is the fact that federal or state resources are often made available when municipal sewer infrastructure breaks. But when a septic tank fails, the homeowner is on their own. And counties can levy fines, or even order evictions if the homeowner fails to fix it quickly. The compounded risk here is staggering.”

“What makes this especially troubling is that communities of color have historically been forced to live in areas vulnerable to flooding, so it’s a one-two punch. Many also can’t afford the high cost of repairing septic systems, which are now becoming more likely to fail,”she said.

"We need to plan and prepare. And we need to do so in a way that is just—that doesn’t leave economically disadvantaged families at greater risk."

Allison Reilly, Assistant Professor of Civil and Environmental Engineering and Pedro E. Wasmer Professor in Engineering at the University of Maryland.

Possible long-term solutions, Reilly said, include enabling states to utilize EPA water infrastructure funds to finance sewer systems expansion or the construction of newer, less hazardous types of septic systems, or making increased use of “green banking” mechanisms that provide low-interest loans for projects that benefit the environment.

Joining her on the EPA-funded project are biofilms expert and UMD CEE associate professor and Diversity, Equity, and Inclusion committee chair Birthe Kjellerup; Rachel Goldstein, assistant professor in the UMD School of Public Health’s Maryland Institute for Applied Environmental Health; Andrew Lazur, a water quality specialist with the UMD College of Agriculture and Natural Resources; coastal hydrologist Celso Ferreira of George Mason University; and economists Yanjun (Penny) Liao and Margaret Walls from Resources for the Future, a DC-based research institution with a focus on environmental, energy, and natural resources issues.

Each will apply their specific domain of expertise to a problem that is interdisciplinary by nature; Ferreira, for instance, will be examining flooding patterns and how they are likely to evolve over time. Goldstein will examine the particular health risks posed by ailing septic systems. "We know that raw sewage can contain disease-causing microorganisms," she said. "If a septic system fails, people could be exposed to these microorganisms and the infections that they cause."

Kjellerup and her students, meanwhile, are taking samples from drain fields in Anne Arundel County and Maryland’s Eastern Shore that are at risk of salt water exposure.

The team is also partnering with SERCAP, which works with lower-income local homeowners to address problems with their homes, including by making repairs to failing septic systems. Jean Holloway, Maryland and Delaware State Manager, will represent SERCAP on the project.

“We need to better understand the risks, and then we need to develop practical, affordable solutions,” Reilly said. “In the past, the approach has too often been reactive–a tank fails, and then its users either have the money to repair it, or they don’t. Such an approach has already left many Americans living in the kind of unsanitary, unhealthy conditions that Catherine Flowers described in her book Waste: One Woman’s Fight Against America’s Dirty Secret, which inspired Reilly and Kjellerup to start discussing this challenge and assemble a team for the project.

“We need to plan and prepare. And we need to do so in a way that is just—that doesn’t leave economically disadvantaged families at greater risk,” she said.

A member of the UMD faculty since 2016, Reilly is an assistant professor of civil and environmental engineering and Pedro Wasmer professor of engineering, as well as a faculty affiliate of the Center for Disaster Resilience. In 2022, she received an NSF CAREER grant to study problems affecting the Federal Emergency Management Agency’s Public Assistance system, which provides disaster recovery funding.

Published February 27, 2023