Septic Systems


Septic systems are the biggest source of nitrogen pollution in Bass River. Over 82% of the River’s controllable nitrogen pollution comes from traditional septic systems, called Title V systems. Although a step up from the cesspools of the past, Title V systems don’t remove enough of the pollutants:  only 21-25% of nitrogen is actually filtered through these systems -- the remainder seeps into the groundwater and into our harbors, coves, and rivers.

Exciting new technology does exist to upgrade septic systems to reduce nitrogen – but it can be complex and costly. The Massachusetts Alternative Septic System Test Center (MASSTC) (operated by the Barnstable County Department of Health and Environment) has been experimenting with a technique of layering soil mixed with sawdust and wood chips below the regular soil treatment area. Aptly called “layer-caking,” this rather simple principle is already being shown to reduce an average of 88% of nitrogen!

There is also inspiring and exciting news from our neighbors on Buzzards Bay who are facing the same challenges as we are on Bass River. Through the efforts of the Save the Bay Coalition, an EPA grant was secured to pilot a subsidy program for qualified homeowners who want to upgrade their septic systems and help clean up the harbor. Two systems are offered: a nitrogen-reducing septic system, which can remove about two-thirds of the nitrogen from a traditional system or cesspool, or an eco-toilet, which can also reduce nitrogen if used and managed properly. By all accounts, this voluntary program will be a win/win: nitrogen pollution will be reduced and homeowners will make a positive investment in the value of their homes.

Until these innovative systems become the norm, a clean, properly working septic system is the responsibility of every homeowner and our best bet to help protect our river. At a minimum, septic systems should be pumped out at least every three years to prolong the life of the system.

And homeowners should recognize signs of a potentially failing system including:

  • Sewage surfacing over the drainfield (especially after storms)
  • Sewage back-ups in the house
  • Lush, green growth over the drainfield
  • Slow draining toilets or drains
  • Sewage odors

Caring for your Septic System: A Reference Guide for Homeowners and Consumer Protection Tips: Septic System Inspections and Repairs published by the Mass DEP outlines do's and don’ts that every homeowner should pay attention to.