Unseen, buried in your yard, it’s constantly at work. While you’re away during the day, it’s at work too. As you sleep at night, it’s still working. Through holidays and all types of weather, it’s working yet. In fact, your septic tank never stops. That is, not as long as you care for it properly. Here’s what you need to know to keep your septic tank working behind the scenes every day of the year.

How a Septic Tank Works

Whether you call it an individual sewage disposal system, an onsite wastewater treatment system, an on-lot system or any combination of terms – a typical septic tank isn’t fancy or complicated. It’s comprised of four main parts:

1. The Waste Pipe: A solid pipe leads from the house and ends at the septic tank. It delivers all household waste flushed from sinks, bathtubs, showers or toilets.
2. The Septic Tank: A buried container, the septic tank is generally about 4 feet wide and 4 feet in depth, with a length of 6 to 8 feet (dimensions may vary depending on home size or, more specifically, number of bedrooms). Watertight, it’s usually made of fiberglass, plastic or concrete. Inside the tank is an inlet tee where the waste pipe enters, separate compartments, and an outlet tee. Additionally, a portion called a riser acts like a porthole, allowing the sludge level to be inspected, and a manhole cover in another area makes easy access for cleaning.
3. The Drain Field: The drain field is an area of land to which the septic tank pumps the liquid portion of the contents. Some states require a reserve drain field as well.
4. Drain Field Soil: Where the magic takes place: as the wastewater enters the soil it’s gradually cleansed of bacteria, viruses and other contaminants. Each time more waste is discharged from the septic tank, previous wastewater is forced deeper into the soil and purified further. Given the proper dirt, the water is clean by the time it reaches the ground water deep below the surface.

So your septic tank doesn’t actually store all the wastewater you use. Instead, it holds it long enough to allow solids to settle to the bottom and begin decomposing, forming sludge. Oils and grease float to the top, forming scum. The water portion flows out through a perforated pipe into the drain field, where it trickles into the ground.

In the meantime, microbes work on the sludge, consuming solid (organic) waste and attempting to turn it all to water (which can then flow out into the drain field as well). What is left eventually gets pumped out and disposed of by a professional septic tank service.

The Importance of Septic Tank Maintenance

If it sounds like a septic tank can do its work without any help, that’s almost true. A properly designed and constructed septic tank “effectively reduce(s) or eliminate(s) most human health or environmental threats” that human waste disposal creates for ground water, the EPA states. However, tanks need some amount of maintenance, or they can – and eventually will – fail.

With septic tank failure, the danger goes beyond needing replacement parts or moving the drain field. If any single piece of the system fails, the results can be devastating. From drain backups inside the home and soggy lawns to infecting groundwater and nearby bodies of water with dangerous bacteria and other nasty ingredients, without care your septic tank can endanger your health and the health of others.

As West Virginia University explains in a publication called “Pipeline,” contaminating ground water leads to pollution of local wells and streams, along with lakes and ponds. Waterborne diseases such as dysentery, typhoid and hepatitis can arise from exposure to the bacteria and viruses in human sewage. Nitrates, phosphates, proteins and nutrients disrupt the balance in bodies of water, causing algal blooms that create untold additional problems. (For example, in 2014 the city of Toledo, Ohio, had a do-not-drink order in effect for several days when an algae bloom in Lake Erie caused high levels of microbes in municipal water supplies along southeast Michigan.)

To avoid these and other problems, practice simple septic tank maintenance procedures.

Septic Tank Use and Maintenance

Homes with septic tanks bear the burden of caring for and keeping their septic tank in good condition, unlike those with city sewer service. In general, important care and maintenance procedures can be divided into three categories: what not to flush or do, water conservation tactics, and maintenance or cleaning requirements.

Dos and Don’ts: What Not to Flush Down Your Drain

You can’t assume that anything that will go down the toilet or drain is okay. While not an exhaustive list, consider the following:

• Do not pour grease and oils down the drains. These quickly solidify, contributing to clogging.
• Avoid excessive use of bleach and other chemical cleaners. Even vinegar and other natural cleaners can alter the bacterial balance in your septic tank. This, in turn, leads to inefficient waste breakdown.
• Do not flush things not meant to be flushed. Sanitary napkins, cigarette butts, tampon applicators, cotton swabs, band aids, condoms, and other items will be slow to dissolve – if they do at all.
• Use napkins and toilet paper that dissolve easily in water. (Test in a glass of water. Drop a small piece in and shake it. If it doesn’t begin to disintegrate, it may be too strong for your septic tank.)
• Avoid pouring gasoline, paint thinner, pesticide or similar items down the drain.
• Dispose of medicines at a local drug store or police station. Never pour them down the toilet.

Water Conservation for a Septic Tank

The more water you use, the harder your septic tank must work. Some experts suggest the typical person uses about 50 gallons of water each day. Try lowering that amount. Implement water-saving habits, and watch how you use the water. You might save money and help conserve resources, too.

• Limit how much you use your garbage disposal. Watch what you put in it as well. Solids such as egg shells and coffee grounds are better thrown away, for instance, as are potato peels which bind up the drain system.
• Place aerators on faucets to have better pressure with less water.
• Switch to a low-flow shower head.
• Buy a water-saving toilet, or put a brick in the tank to displace water. This allows you to use less water per flush.
• Watch your load size when doing laundry. Use only as much water as needed.
• Eliminate drips from fixtures.

Septic Tank Care

Perhaps not the most urgent part of septic tank maintenance – but just as important – is how you take care of your drain field and clean your tank. A few guidelines:

• Keep cars, heavy tractors or other motorized vehicles off the lawn near the drain field and septic tank.
• Plant grass over the tank and drain field, but avoid trees or shrubs. These plants grow roots that may interfere with drainage or penetrate the tank.
• Avoid installing swimming pools, decks, patios, sheds or other items in the septic system area.
• Refrain from making any alterations to the septic tank or field.
• Test the sludge level as directed by the tank manufacturer yearly.
• Pump waste solids from the tank as necessary. As a rule of thumb, expect to pump every three years for a family of four with a 1,000 gallon tank. Refer to this New Mexico State University Cooperative Extension chart for different tank sizes and loads.

A word about pumping out the waste: Hire a professional septic tank service. They have the knowledge and equipment to do it properly, without danger to you. Sewer gases can easily overcome you in minutes and kill. Also, make a diagram of your tank and drainage field to help future homeowners if you sell, or if you forget. Keep a list of all repairs and cleanings as well.