RI - The Possible Future of Septic Systems: A Simpler, Cheaper Nitrogen-Removing Design
Nitrogen pollution from failing septic systems, which impairs coastal waters, continues to be a problem in Rhode Island. The solution can be expensive.
CHARLESTOWN, R.I. — A simpler, less-expensive, advanced on-site wastewater treatment system will soon be undergoing field tests in Rhode Island.
In the coming weeks, the Rhode Island Department of Environmental Management (DEM) is expected to approve a pilot project to test an experimental nitrogen-removing septic system known as “layered soil treatment area” — or LSTA for short.
Proposed by a consortium of the town of Charlestown and the University of Rhode Island’s Laboratory of Soil Ecology and Microbiology and New England On-Site Wastewater Training Program, the non-proprietary septic system would put nitrogen-removing technology within reach for more coastal homeowners.
Since 2008, the state has required that failing septic systems in the coastal zone be replaced with advanced nitrogen-removing wastewater treatment systems. The requirement also applies to new construction and to major rebuilds.
However, despite the more-stringent regulations, nitrogen pollution, which causes algal blooms, oxygen depletion, and fish kills, continues to be a problem.
A 2016 study, funded by a $674,000 grant from the Environmental Protection Agency, $20,000 from the town, and in-kind contributions from the Salt Ponds Coalition and Save The Bay, showed that even with advanced treatment systems, nitrate levels in groundwater in some Charlestown neighborhoods and in the town’s salt ponds remained high.