Flushed and forgotten: Study finds septic tanks may require more frequent maintenance

Moved into a house with a “new” septic tank? You might want to have it inspected sooner than you think.

A recent study out of the University of Georgia shows that younger septic systems—those between two and 10 years old—often exhibited hydraulic issues similar to much older systems, a problem that can lead to impaired water quality in the surrounding environment.

Owners, therefore, should have their systems inspected at least late in their life—50 years or older—but also within a year of their installation. Given their findings, however, best practice indicates that more routine pumps would be ideal—but costly.

“Approximately 25% of U.S. households depend on septic systems to treat their sewage on their own property, and in some regions—such as the Southeast—dependence on septic is even more common,” said Krista Capps, an associate professor in UGA’s Odum School of Ecology. “Guidance suggests you should get your tank pumped every three years and have it regularly inspected. Most homeowners, however, do not follow these guidelines.”

One challenge, Capps said, is the financial burden. The cost of pumping a system by reputable companies has increased from a few hundred dollars to $500 or more locally over the past decade, due in large part to the limited number of vendors that can legally and affordably treat septage once it is removed from the tank.

“Replacing a system can cost tens of thousands of dollars,” said Capps, who shares a joint appointment with the Savannah River Ecology Laboratory. “This far exceeds what many homeowners can pay.”

Improving maintenance of septic infrastructure, she said, will likely require new policies and accessible resources in support of affordable treatment.

Septic tanks, also known as onsite wastewater treatment systems (OWTS), are gray infrastructure common to most of the United States. Initially trained to work in relatively pristine rivers and streams, Capps collaborated with local and regional governments to address environmental concerns facing the Athens and Georgia communities. Along with colleagues in the River Basin Center, she examined systems around the Athens-Clarke County area to assess maintenance patterns in county septic infrastructure to try to identify characteristics of failing systems.

When systems malfunction, they can release untreated wastewater into the surrounding environment and compromise water quality for communities living downstream. In Georgia, many rivers and streams are impaired because of high concentrations of gut bacteria like E. coli. Untreated sewage from septic systems can cause or exacerbate this problem.