Avoiding Septic Shock: How Climate Change can cause Septic System Failure and Whether New England States are Prepared

This white paper discusses climate change impacts on septic systems in New England, and whether states in the region are prepared for these impacts. The paper provides a state-by-state analysis of septic system regulations in New England and discusses how these regulatory frameworks are not fully considering climate change impacts, especially groundwater table rise. It also identifies challenges in septic system regulation, and suggests recommendations and best practices for how states and municipalities can work to change laws, amend rules, or adopt new policies or incentives to better construct, manage, and regulate septic systems to be resilient to climate change.

Almost half of homes in New England utilize septic systems to dispose of wastewater - and when functioning properly, these systems filter out bacteria and pathogens to ensure nearby groundwater and surface waters are safe for human health and the environment. However, this research finds that states in the region are not adequately addressing climate change impacts when regulating the location, operation, or inspection of septic systems. Climate change is impacting these onsite wastewater treatment systems through rising sea levels and groundwater, increased precipitation and storms, and warmer temperatures.

According to the report, sea-level rise can cause near-shore groundwater tables to rise as saltwater intrudes into groundwater reservoirs, and can reduce separation distances to the leachfield base, compromising the systems’ ability to treat bacteria and pathogens in wastewater. Increased heavy precipitation events also contribute to a rising groundwater table - as well as the saturation from increased precipitation depletes oxygen in soils, compromising aerobic microbial activity and resulting treatment of wastewater.  In addition, higher air temperatures further compromise healthy aerobic microbial function due to greater oxygen demand that effects biochemical treatment processes in the soil.

Recommendations provided in the report highlight some best practices that states and local municipalities could adopt to ensure septic systems that are resilient to climate change. Detailed reasoning is given along with the regulatory potential for the following strategies:

  1. Incorporate future seasonal high water table projections when siting septic systems.
  2. Implement state-level mandatory inspections, at least at the point of sale of any home.
  3. Heighten State-level Regulations to ease burden on municipal enforcement.
  4. Monitor system treatment performance, as opposed to just system operability.
  5. Create, or further implement a risk-based tiered approach, where areas susceptible to groundwater rise or other contact with surface waters are more protected from wastewater contamination.
  6. Require advanced/innovative septic treatment systems in high-risk areas.
  7. Create incentive programs to encourage residents to address failing septic systems, and/or switch over to advanced/innovative septic treatment systems.
  8. Create a public outreach program to inform residents on septic maintenance, inspection, and pumping.
  9. Support local research to identify areas at risk of septic system failure due to anticipated groundwater rise, and test the treatment effectiveness of various alternative technologies.


Publication Date: February 2017

Author or Affiliated User:


Resource Category:

Resource Types:

  • Assessment
  • Policy analysis/recommendations

States Affected:


Go To Resource