How Septic Systems Work | Onsite Overview #3

Whether you are a septic system homeowner or an onsite wastewater professional, it is important to know all you can about the ins and outs of septic systems. Whether it be the basics of how they work, what types are available, or how to clean a septic tank, there’s no such thing as being overeducated when it comes to such an integral aspect of so many homes in the U.S. We have compiled a list of resources to get you started if you are interested in learning how to properly care for and maintain a septic system.

Our best resources on this topic:
About Septic Systems | Oregon Department of Environmental Quality
This webpage provides a brief introduction to septic systems, how septic systems operate, an inspection checklist for those who are planning to buy a property with a septic system, how to go about getting a new septic system installed, and a septic system maintenance fact sheet.

All About Septics | University of Minnesota Onsite Sewage Treatment Program
This webpage provides detailed information on septic system types (type i and iii systems), advanced treatment systems (type iv systems), special situations, and other onsite treatment areas of interest.

Septic System Basics Video: Septics 101 Course | Washington State Department of Health
This 19-minute video intended for homeowners explains the basics of how on-site sewage systems function and the steps you should take to keep your system working well. The video is divided into 5 chapters that can be viewed separately. Chapters include: Introduction and Sewage Overview, System Basics and Soil, Types of Septic Systems, and System Care & Maintenance.

Cleaning an Onsite Sewage System | Indiana Onsite Wastewater Professionals Association
This 2-page fact sheet provides onsite owners some basics about the system. These include: How an Onsite Sewage System Works, Inspection of the System, Cleaning the Outlet Filter, and Cleaning the Septic Tank. Additional references are also included in this fact sheet.

Septic Tank Pumping | Idaho Department of Environmental Quality
This 11-page manual was developed to help pumpers understand these important aspects of septage handling and disposal. Topics covered are: Septic System Components, Checking the Level of Scum and Sludge in a Septic Tank, Permit Requirements, Septic Tank Pumping, Equipment for Pumping and Transporting Septage, Septage Storage, and Septage Disposal.

How to find more resources on this topic on our website?
If you are interested in looking through our database for other resources on this topic follow the instructions below:

1. Select "CATEGORY" in the dropdown then choose "Decentralized WW Systems." 
2. Once you make that selection, a second dropdown will appear where you can choose "TYPE" if you are looking for a specific kind of resource (videos, factsheets, etc.)
3. Optional: In the Keyword Filter, you can type a specific word or phrase to target the search even further.
4. The last step is to click the "Retrieve Documents" button to see your results. 

Septic System Contamination Risks

Can a septic system contaminate a well?

Have you ever thought about where the water goes when you flush a toilet? If you have a septic system, this question may be more important than you think. Whether it is the largest advanced wastewater treatment plant in the world or the septic system in your back yard, all wastewater systems need regular maintenance. This will not only extend the life of your system, but it will also help prevent it from potentially contaminating the surface water and groundwater.

How does a septic system contaminate the surface water and groundwater?

Water from your toilets, showers, and other appliances contains harmful bacteria, viruses, and nutrients that could make you sick if it were to enter your well without being properly treated first. Maintenance issues like a full or cracked septic tank or a plugged drainfield can cause untreated wastewater to enter the surface water or groundwater.  
According to the United States Environmental Protection Agency (EPA), the most serious documented problems involve contamination of surface waters and ground water with disease-causing pathogens and nitrates.

Let’s take a peek at a conventional septic system and see how contamination can occur:

Your House:

• Most of the wastewater will generate from the kitchen and bathroom. Watch what you put down your drains. 
• Remember the three P’s: poop, pee, and (toilet) paper. Those are the only things that should be flushed down a toilet. 
• Avoid flushing other chemicals or medications down the drain or toilet as they could contaminate your well. 

Septic Tank: 

• Wastewater exits the home through a pipe and enters the septic tank which is buried and watertight.
• The solids settle at the bottom forming sludge, while fats, oils, and grease float to the top and form scum. Sludge is broken down by microorganisms that also destroy some of the contaminants in the wastewater. 
• If a tank is leaking, contaminated wastewater will exit the tank before it is treated. A septic tank needs serviced and pumped on a regular basis to ensure it is working properly.

Drainfield: 

• In your yard, a series of shallow trenches were placed to create the drainfield. The partially treated wastewater flows from the septic tank into the drainfield and slowly filters down through the soil until it reaches the groundwater.  
• Overloading your drainfield with too much water or having it clogged with solids will cause sewage to surface in your yard or even back into your house.

Treatment in the Soil: 

• Most bacteria, viruses, and some nutrients are removed when the wastewater filters through the soil.
• Soil cannot remove all medicines, cleaning products, and other harmful chemicals, so they pose the risk of entering the groundwater. 
• Wastewater that surfaces in the yard may contaminate your drinking water through an unsecured cap or cracks in the well casing.

Groundwater: 

• Groundwater is water that is beneath the Earth’s surface and is held in the soil or in the pores and crevices of rocks. 
• Any contaminants that remain after leaving the septic system may seep into the groundwater. 
• The biggest risk for a well to become contaminated is if it is in the path of groundwater flow beneath a septic system.

Further Resources:

• Septic Systems and Drinking Water | Diagram & Table from EPA
• Understand Your Pump Septic System | 3D model from TPC HD
• How does a Septic System Work? | Video from SEFC

RCAP’s Onsite/ Decentralized Program

RCAP (Rural Community Assistance Partnership) has an onsite/decentralized program that provides training, technical assistance, and financial resources to assist individual homeowners, neighborhoods and entire communities that rely on inadequate septic systems for their waste disposal. 

This program is mostly funded by U.S. EPA through the Rural Treatment Works and National Priority Area 2 grants. RCAP can offer hands-on training with community members, sanitarians, and any professionals who work with onsite systems as well as technical assistance. RCAP has been participating in the Biden administration’s Closing America’s Wastewater Access Gap Community Initiative in six of the 11 pilot communities located in persistent poverty/ disadvantaged areas.

Recently, we spoke with Sarah Buck, RCAP’s Chief Programs Officer, and she provided more information on this valuable resource for anyone working with onsite/decentralized wastewater systems. 

How does this program allow RCAP to help people with onsite/decentralized systems?

There are many ways that this program can help!

• With technical assistance providers, we can help set up a responsible management entity (RME) for decentralized systems.
• We’re able to do mapping activities to map septic systems in a community.
• We can look at areas with high concentrations of septic systems that pose environmental & health risks and help them review all of their options including interconnecting them or assisting with setting up a publicly owned water treatment works or decentralized system.
• We can help find funding to fund these types of projects in disadvantaged communities.

What are the eligible areas?

• Training and technical assistance generally is for communities of 10,000 or less in all 50 states and the US Territories including on Tribal lands/for Tribal septic owners.

Is there financial assistance available?

• Most of RCAP’s regional partners participate in the USDA Decentralized and Well Revolver Fund which provides funding that well and septic owners can use for replacements or updates.

How to apply for assistance? 

• Go to RCAP’s website and fill out the “Get Assistance” Form which will go to someone at the national office. They will then send that form to a regional partner near you to set up a technical assistance consultation.
• Find your local provider on RCAP’s website and contact them directly.
• Fill out U.S. EPA’s Water Technical Assistance Request Form and be assigned a provider that way.

Who are the partners that are assisting with this program?

• RCAP & their 6 Regional Partners
  • Rural Community Assistance Corporation (RCAC) – The Western RCAP
    • Serving Alaska, Arizona, California, Colorado, Hawaii, Idaho, Nevada, New Mexico, Oregon, Utah, and Washington
  • RCAP Solutions (RSOL) – The Northeastern and Caribbean RCAP
    • Serving all six New England States, New York, New Jersey, Pennsylvania, Puerto Rico, and the U.S. Virgin Islands
  • Midwest Assistance Program (MAP) – The Midwest RCAP
    • Serving Iowa, Kansas, Minnesota, Missouri, Montana, Nebraska, North Dakota, South Dakota, and Wyoming
  • Southeast Rural Community Assistance Partnership (SERCAP) – The Southeastern RCAP
    • Serving Delaware, Florida, Georgia, Maryland, North Carolina, South Carolina, and Virginia
  • Communities Unlimited (CU) – The Southern RCAP
    • Serving Alabama, Arkansas, Louisiana, Mississippi, Oklahoma, Tennessee, and Texas
  • Great Lakes Community Action Partnership (GLCAP) – The Great Lakes RCAP
    • Serving Illinois, Indiana, Kentucky, Michigan, Ohio, West Virginia, and Wisconsin
• National Onsite Wastewater Recycling Association (NOWRA)
• WaterOperator.org
• Inter Tribal Council of Arizona (ITCA)
• Moonshot Missions (a new national EFC)

Further Resources?

• Sign up for A Drop of Knowledge and Rural Matters to receive updates on work RCAP is doing
• RCAP hosts multiple webinars a year dedicated to onsite/decentralized topics | View Archive
• New Onsite Wastewater Treatment System User Guide created in collaboration with NOWRA | View PDF
• Developing a new Septic Assessment Tool in collaboration with WaterOperator.org that will be piloted fall 2023 and will be available as a fillable PDF online

How Did You Support SepticSmart Week?

The United States Environmental Protection Agency (U.S. EPA) hosted the 11th annual SepticSmart Week from September 18-22, 2023. Many water industry professionals took to social media to share U.S. EPA's helpful tips with septic system owners in their communities.

1. Think at the Sink! What goes down the drain has a big impact on your septic system. Fats, grease, and solids can clog a system’s pipes and drainfield.
2. Don’t Overload the Commode! A toilet is not a trash can. Disposable diapers and wipes, feminine hygiene products, coffee grounds, cigarette butts, and cat litter can damage a septic system.
3. Don’t Strain Your Drain! Use water efficiently and stagger use of water-based appliances. Too much water use at once can overload a system that hasn’t been pumped recently.
4. Shield Your Field! Tree and shrub roots, cars, and livestock can damage your septic drainfield.
5. Keep It Clean! Contamination can occur when a septic system leaks due to improper maintenance. Be sure your drinking water is safe to drink by testing it regularly.
6. Protect It and Inspect It! Regular septic system maintenance can save homeowners thousands of dollars in repairs and protect public health.

This year's SepticSmart Week creative challenge was in partnership with Youth Engaged 4 Change and asked students ages 11-19 what “septic systems of the future” might look like. Participants were encouraged to demonstrate their thoughts on how future septic systems could sustainably safeguard community health and protect waterways. The top three winners received $100 gift cards and included Tyler’s Diagram showing a new and improved drain field regulator, Karolina’s Poem “Future Septic Systems”, and Ahana’s Essay “Septic Systems of the Future.”

Featured Videos: Onsite Wastewater Systems

According to the US Census Bureau, one in four homes in the U.S. is served by an onsite wastewater system. Our first featured video this week explores some of these onsite options and then explains in simple terms how each of these systems work in different soil conditions and what it takes to maintain them. In the end, the video shows how the cost-effectiveness of septic systems can often more than outweigh the cost of a centralized system for many smaller communities. 

Wondering how to find the funding to get these types of decentralized systems off the ground? Our second video this week explores how innovative partnerships and Clean Water State Revolving Funds can be used for exactly these kinds of projects.