Program Education, Outreach and Resources


How Your Septic System Can Impact Nearby Water Sources

Septic systems can impact local drinking water wells or surface water bodies. The extent of this impact depends on how well your septic system is maintained and if it is used properly. Click on the links below to learn more about how septic systems interact with drinking water wells or surface water bodies and how to keep them healthy.

Click to learn how to protect drinking water wells

Septic Systems and Drinking Water

Septic systems provide wastewater treatment for many homeowners who also often get their drinking water from private wells. If a septic system is not working properly or is located too close to a drinking water well, contaminants from the wastewater can end up in drinking water. Learn how to locate, operate, and maintain your septic system to protect nearby wells.

Learn how waters near your home may be affected

Septic Systems and Surface Water

Many homeowners rely on septic systems for safe and effective treatment of their wastewater. Household wastewater is treated by a septic system before it filters into the soil. Recycled water from a septic system can help replenish groundwater supplies; however, if the system is not working properly, it can contaminate nearby waterbodies. Learn how nutrients and pathogens from your septic system may impact streams, lakes, or other waterbodies near your home. 


Click to learn how to keep nearby waters healthy

Septic System Improvements to Protect Nearby Water Sources

As a homeowner, there are several steps you can take to prevent your home's septic system from impacting nearby water sources. Some are simple while others can be more involved and expensive. Consult with a professional in your area before making significant upgrades to your septic system.


Content from United State Environmental Protection Agency:

This is a simplified overview of how a septic system works.

depiction of wastewater system

Water runs out of your house from one main drainage pipe into a septic tank.

The septic tank is a buried, water-tight container usually made of concrete, fiberglass or polyethylene. Its job is to hold the wastewater long enough to allow solids to settle down to the bottom (forming sludge), while the oil and grease floats to the top (as scum). Compartments and a T-shaped outlet prevent the sludge and scum from leaving the tank and traveling into the drainfield area.

The liquid wastewater then exits the tank into the drainfield. If the drainfield is overloaded with too much liquid, it will flood, causing sewage to flow to the ground surface or create backups in toilets and sinks.

Finally, the wastewater percolates into the soil, naturally removing harmful bacteria, viruses and nutrients.

The Regional Office Program issues water/wastewater permits (WW Permits) for soil based wastewater systems with flows of less than 6500 gallons per day, for potable water supplies (water supplies that are not public water supplies), and for municipal water and sewer connections. Permitting staff are located in five Regional Offices. Staff also administers the licensed designer program and reviews innovative and alternative systems for potential use in VT.

The regional offices map provides office, program and contact information for each region.

Licensed Designer Program information.

Information for Landowners






Full Delegation Template
Partial Delegation Template




How do I test my private well?