Septic System Maintenance is Crucial for Water Quality

When septic systems fail they contaminate lakes and streams in our watershed.

Learn more in this interactive diagram from the EPA.

Septic Rules in Watershed Towns

Because failing septic systems release bacteria and viral pathogens into waterbodies, RSA 147:1 gives town Health Officers the authority to adopt regulations ensuring that wastewater disposal systems shall not be a nuisance or injurious to public health. Failing systems leach nutrients like phosphorus and nitrogen into the water which can result in toxic cyanobacteria blooms. You can read examples of septic rules from towns across New Hampshire here.

Town of Sunapee

In March 2023, the Town of Sunapee’s Selectboard adopted regulations proposed by the Health Officer requiring that “All developed properties with septic systems in the shoreline overlay district in the Town of Sunapee shall be pumped a minimum of once every three years.” You can read the full septic rules for the Town of Sunapee here.

Town of Springfield

In October 2024, the Town of Springfield’s Health Officer proposed that a new section be added to the town’s regulations of sewage disposal systems and wells. This proposal included the following language: “Everything in the watershed ultimately drains into our groundwater, streams and lakes. Any leaking or failing septic system regardless of proximity to our lakes can have a negative impact on water quality. This is a community issue that requires all residences to participate. Every septic system should be pumped and inspected a minimum of every three years.” You can read the new policies in Section 8 of Springfield’s Regulation of Sewage Disposal Systems and Wells document here. Springfield’s regulations were adopted by the Selectboard on November 11, 2024 at a session that included a public hearing.

Town of New London

The New London Health Officer introduced proposed septic regulations to the Selectboard at their November 21st meeting.  The Selectboard met again on December 19, 2024 and voted to adopt the proposed rules. The effective date of the regulations will be January 1, 2026. Residents are encouraged to voluntarily pump their systems prior to the effective date of the rules. You can find out more about the rules here.

Town of Newbury

Septic regulations were proposed in Newbury and brought to Town Meeting in March 2023, but failed to pass. LSPA wrote a letter in support of these regulations which you can read here. The Selectboard has appointed community members to form a Septic Committee to “explore, report and recommend rules for septic pumping” to the full Selectboard. You can learn more about the committee here.

Are septic system failures a problem in the Lake Sunapee Watershed?

Yes, NH DES has documented septic system failures every year since at least 2015 in every town with shoreline on Lake Sunapee. Actual failure rates are likely much higher than shown in the graph below because not all failures are reported to NHDES. Failures can contaminate groundwater and well water as well as streams, lakes and ponds.  

Statewide Septic System Policies

Failed Septic Systems

The state of New Hampshire requires that septic system failures must be addressed by property owners. New Hampshire RSA 485-A:2 defines failure as “the condition produced when a subsurface sewage or waste disposal system does not properly contain or treat sewage or causes the discharge of sewage on the ground surface or directly into surface waters, or the effluent disposal area is located in the seasonal high groundwater table.” Failures can be reported to NHDES by town health officers, permitted designers or other local officials responsible for health code enforcement. You can find more information here.

Real Estate Transfers

In September 2024, a new law took effect that requires buyers of properties to have individual sewage disposal systems (e.g septic systems) evaluated by a permitted septic system evaluator. You can read more about this law regardingTransfers of Waterfront Properties with Individual Sewage Disposal Systems in the Protected Shoreland here.

How to take care of your septic system responsibly

Proper septic system maintenance is critical to help protect the water quality of a lake and will also help extend the life of the septic system. Frequent pumping and regular inspections protects nearby groundwater and surface waters. A septic system that is well maintained can last for 30 to 40 years before needing major work done or replacement. You can read about home septic system maintenance here. If you need information about your current septic system, you can contact your town’s health officer for more information.

  • Routinely Clean & Inspect the System

    Have a septic service professional pump your tank and clean filter(s) every 3 years or sooner and inspect entire system frequently. This includes looking at all components (not just the tank) and acting on recommendations given in the follow-up report.

  • Protect the Drainfield

    Keep field clear of trees and shrubs and avoid driving on it to prevent damage to system.

  • Practice Indoor Water Conservation

    Fix leaks, install low flow fixtures, use water efficient appliances and spread out daily indoor water use to minimize stress to system.

  • Flush Only Toilet Paper

    Don’t use your toilet as a trash can!

  • Limit What Goes Down the Drain

    Don’t dispose of grease, food waste, chemicals or paint down the drain and avoid using a garbage disposal. These materials can prevent the system from operating properly and will harm the good bacteria that helps your septic system run properly.

How does a septic system work?

The main purpose of a septic system is to treat wastewater from your home (or small business).  In New Hampshire, most septic systems include a septic tank and a leach field (or drainfield).   All water that goes down a drain flows out to the septic tank through underground pipes.  The heavier solids settle at the bottom of the tank and the lighter solids, such as grease and oil, float to the top of the tank.  The remaining wastewater then leaves the tank through a series of pipes and disperses into the leach field.  It is filtered through the soil, removing any harmful bacteria, and then eventually enters back into the system as groundwater. Click here to read more about how septic systems work.

Septic System Additives

According to the EPA and NH Department of Environmental Services, the effectiveness of additives has not been determined. Studies show additives have no significant effect on speeding up the decomposition process that occurs with naturally existing microbes found in septic tanks and drain fields. The best way to extend the life of your system is to practice routine maintenance and limit what you dump down the drain as described above.

Need to find a septic service professional?

Septic System Maintenance

Here is a list of septic system service professionals who service towns in the Lake Sunapee Watershed. LSPA does not promote or endorse any of the companies listed.

Septic System Design and Installation

You can find septic system designers and installers throughout the state of New Hampshire here. This link provides info on septic system designers, installers, evaluators and maintenance personnel in New Hampshire, however it is not all inclusive. You can find a detailed list of prequalified engineering firms from NHDES here.

For more information visit the following websites:

EPA’s Septic Sense

Septic Systems - NHDES