What Is a Septic System and How Does It Work?

A septic system is an alternative to public waste management with a series of components that treat household wastewater on site. Most septic tank systems are in rural areas or places that do not have municipal sewer systems. If you are a first-time septic system owner, you likely have several questions about managing your new system and avoiding potential hassles or complications. While traditional wastewater systems use city or municipal-based sewer systems, a septic tank system is self-contained on an individual property and maintained by the homeowner — proper care and inspection become your responsibility when you purchase a property with a septic system. Specialized professionals inspect septic tanks and the system’s components. A traditional home inspection does not typically review a septic tank system. Read this comprehensive guide to learn everything you need to know about septic tank systems and how they work.

How does a septic tank system work?

Think of your septic system as a miniature sewer system that only processes the water waste from your home. Several components comprise a septic system, all working in tandem to process water from your toilet, sink, shower, dishwasher, and washing machine. There are two main sections of a septic tank system—the septic tank and the drainage field.

Septic tank

Household wastewater travels through an exit pipe into a large underground tank called the septic tank. Three layers work together to make a septic tank work: sludge, scum, and effluent. The sludge is a collection of solids that sits at the bottom of the tank. Bacteria in the tank break down these solids over 24 to 48 hours, creating a sludge-like base layer. The top layer is a collection of lighter floatable solids, grease, oils, and fats known as scum. In between the sludge and scum sits the remaining wastewater, called effluent. The bacteria partially clarify the effluent. 

Drainage field

As the septic tank fills up, the effluent travels through a pipe and empties into the drain field. A drain field is a large area next to the septic tank where the remaining wastewater absorbs into the soil. The liquid drains through a perforated pipe into a deep layer of gravel. Geotextile fabric sits above the gravel layer with an additional layer of sand and loam soil at the surface — the effluent sinks through the soil absorption field, which sits below the gravel layer and above groundwater. Naturally occurring bacteria filter and digest any remaining contaminants in the wastewater. Once the effluent reaches the groundwater level, it’s fully treated and ready to be reincorporated into the groundwater.

Septic system vs. sewer systems

There are many differences between septic and municipal sewer systems. However, the end goal is the same. Both systems work to cleanse wastewater so that it can be reincorporated into the primary water source. The most notable difference between a septic and a sewer system is who is responsible for the maintenance. When you have a sewer system, the city or municipality is responsible for maintaining the sewer lines, flow, and wastewater treatment. Septic tanks are the responsibility of individual homeowners. The cost of sewers and water treatment typically factor into a water bill with prices set by a local management company. It can range anywhere from $14 to $35 per month. A septic system’s overall cost depends mainly on the water used, the home’s size, and the continued maintenance to keep the system running efficiently. The average maintenance contract with a professional company ranges between $150 and $300 per year.

Septic system maintenance 101

Proper maintenance is crucial to keep your septic system in good working order and avoid expensive repairs or complicated clean-ups. Here are a few maintenance tips to keep in mind for keeping your septic tank performing well.

Pump your tank

How often you pump your tank depends on your household size, water usage, the number of solids, and the tank size. The EPA recommends having your system pumped every three years. Having your tank inspected more frequently, especially if you have heavy water use in your home, is a good idea, ensuring you don’t miss a necessary pumping. Keep detailed records of your wastewater service records so you stay on schedule. Work with a local company to determine the best plan for your tank.

Make conscious choices

One of the best things you can do to keep your septic system healthy is to be mindful of what goes down the drain. Whether in the bathroom, kitchen, or mudroom, ensuring your household stays cautious about what makes its way to your septic tank will eliminate hassle down the road. Remember, water from the shower, hot tub, garbage disposal, toilet, and washing machine all head to your septic tank. Make simple-to-follow lists in rooms with drains to help remind everyone what is okay and what isn’t. A good rule of thumb is to avoid the following types of material from entering your drainage system:

  • Fat and grease
  • Chemicals or drain cleaners
  • Motor oil and fuel
  • Disposable diapers
  • Dental floss
  • Coffee ground, eggshells, and nutshells
  • Filter tip cigarettes and cigarette butts
  • Sanitary napkins, tampons, and condoms
  • Paper towels or rags
  • Soaps and cleaning products that include harmful chemicals
  • Excessive ultra-thick toilet paper
  • Paint, household chemicals, and harsh detergents

Keeping these items out of your septic system is a great way to maintain a productive system and avoid the build-up of bad smells.

Use additives as needed

Bacteria additives are live organic bacteria that work to break down the sludge in your septic tank. Using these additives replaces natural bacteria that the collection process kills. They are an inexpensive way to keep your system functioning correctly. Consult a licensed septic system inspector on the best products for your tank.

Maintain your drain field

It’s easy to neglect the drainage field since it’s primarily self-reliant. The best ways to keep it in working order are to prevent equipment, livestock, or vehicles from moving on it. Don’t plant trees or deep-rooting vegetation near your drain field to avoid the introduction of roots. Ensure your gutters, sump pumps, and HVAC drains don’t lead toward your drainage field.

Conserve water

Remember, every drop of water your household uses ends up in your septic tank. Try to create a household environment that focuses on water conservation wherever possible. Installing low-pressure shower heads and faucets, water-saving toilets, and high-efficiency washers is a great way to support lower water use. If something causes a significant uptick in water usage, such as a heavy rain storm or visiting houseguests, make sure to schedule a quick inspection as a cautionary measure.

Stay vigilant

Check your septic tank system often and know the signs of a potential problem. Some signs of an overloaded system are:

  • Unpleasant odor
  • Obvious surface sewage
  • Lush vegetation in the drain field
  • Random wet spots in the lawn
  • Gurgling noises from the plumbing
  • Slowly draining fixtures
  • Plumbing backups

In any of these cases, scheduling immediate maintenance is the best way to head off a problem. Ask your septic inspector what telltale warning signs to look out for based on your specific setup.

Hire professionals

Compare and contrast your local service providers and inspectors to ensure you hire the right company with the necessary experience and know-how to care for your septic tank system expertly. No matter who you hire, ensure they’re certified, backed by positive reviews, and have a glowing reputation. Find a company you can build a relationship with over time so they can learn the nuances of your system and set you up for long-term success.

How does a septic system inspection work?

A professional septic inspector assesses each component of your system to ensure it functions correctly and doesn’t require any repairs or maintenance. You’ll want to maintain scheduled septic checks and inspections every so often, especially before putting your home on the market. The inspector will check for many things to confirm your system is in working condition. This process eliminates surprise problems that can come with high price tags.
Work with a local company to schedule a septic tank system check every few years. Remember, this forethought ensures your system runs smoothly and prevents possible disasters and costly repairs. With these tips in mind and some dedicated diligence, you can keep your septic system in optimum condition for a long time. If you’re a home inspector, visit our website to learn more about our software features today.