If you live in the country and have a water softener, what should you do with the backwash water? Discharge it to your septic system? Pipe it into a separate trench?

For the time being, that's an open question, and NOWRA and at least one state regulatory agency are trying to reach a resolution. Some in the onsite industry claim brine discharges from water softeners harm septic system function. Others, including the Water Quality Association (WQA), which represents the water softener industry, disagree.

To their considerable credit, the parties to this debate have not simply stood on opposite sides and tossed rock salt at each other. They're trying to resolve the question scientifically and conclusively so that everyone concerned – from homeowners to plumbers to onsite installers – knows how to handle backwash properly.

Study committee

At the national level, NOWRA and the WQA began working this issue cooperatively in 2010. The WQA proposed a study of the issue, and several NOWRA members joined a committee to design and direct the study,
now complete and awaiting a final report. The committee also includes representatives from the State Onsite Regulators Alliance, NSF and
other organizations.

Leading the research was John Novak, Ph.D., P.E., professor of civil and environmental engineering at Virginia Tech. His work included experiments in which he added varying levels of sodium to wastewater influent, then fed it to columns that contained solids from operating septic tanks. He also conducted experiments to determine how sodium affects the production of gases and the degradation of solids and investigated influent slug loads designed to mimic softener discharges. Researchers also compared samples from septic tanks that receive softener flows and from which such discharges are diverted.

NOWRA executive director Eric Casey has called the project "an excellent example of two organizations recognizing an issue in the industry and working in a forthright, constructive way to provide a scientific response." He observes that both parties are comfortable with the science and the way study was conducted. Watch for the research report later this year.

Three-way discussion

Meanwhile, three parties in Minnesota are working on the same basic issue: The Minnesota Pollution Control Agency (which regulates onsite systems), the University of Minnesota (which educates and trains people about onsite systems) and state Department of Labor and Industry (which regulates plumbing).

It turned out that those entities were not in sync about the proper disposition of softener discharges for rural homes, according to Gretchen Sabel, coordinator of the Subsurface Sewage Treatment Systems (SSTS) program for the MPCA.

"The university was saying don't put softener discharge into a septic system," she notes. "Labor and Industry was saying backwash was sewage and had to go in the septic system. MPCA was saying the backwash could go into the septic system or into another specially designed trench – it just could not be discharged on the surface."

Representatives from those three entities have been meeting informally to work toward a resolution. They met most recently last January. The ideal scenario, according to Sabel, would be to issue a fact sheet resolving the question in time for this spring's construction season, so that people out in the field know what they should be doing.

These groups are to be commended for working cooperatively. Industry practitioners should be watching for the results with considerable interest.

Clarification

The "Breaking Ground" column in the December issue of Onsite Installer suggested that onsite professionals offer their customers signs to post next to their toilet tissue holders saying: "S.O.S. (Save Our Septic): Please flush nothing except toilet tissue."

A representative from Bio-Microbics, a manufacturer of treatment units for onsite systems, has since notified the magazine that "S.O.S.- Save Our Septic" is a registered trademark for a prevention and remediation program that company offers with its RetroFAST septic system enhancement product, a remedy for failed septic systems.

Onsite Installer regrets any confusion that may have been caused by our suggested wording for an educational card.