Septic Tank Care & Maintenance

Proper septic tank maintenance includes regular inspections, periodic pumping and awareness when using the plumbing.

If you're getting ready to move from the city to a rural area, one of the changes to prepare for is life on a septic system. Unlike a municipal sewage system, a septic system requires maintenance, and because it's on your property, no municipal authority will do it for you. If that information makes you stiffen your shoulders and clench your teeth, relax. Maintenance is easier than you think.

Septic System Basics

As a sewage treatment facility, the purpose of a septic system is to purify water from your drains and toilets sufficiently to allow it to return back into the water table from whence it came. The principle behind a passive treatment system -- which is the most common -- is simple.

Water enters a tank in which solids sink to the bottom, and greases and oils rise to the top. The water between the bottom sludge layer and the top scum layer is fed by gravity or a pump to a drainfield where it percolates into the ground, allowing the soil to purify it. The tank is the heart of this system and needs TLC to remain healthy.

Tank Maintenance

Know When to Pump

Septic professionals usually recommend pumping your tank every three to five years, but it really depends on what you put in the tank and how often you use it. You should conduct a simple test yearly to determine whether the tank needs pumping:

    Locate the tank.

  1. Tanks are usually buried, and if you don't know where yours is, consult your property map on file at the county office. You can also find it by excavating with a straightened coat hanger. You'll probably have to dig to find the cover.

  2. Check the sludge level.

  3. Insert a stick long enough to reach the bottom of the tank through the tank opening -- after removing the cover -- and pull it out to check the sludge level. It should be less than one-third the level of the entire contents of the tank. If it's any higher than that, it's time to get the tank pumped.

  4. Check the drainfield.

  5. Smells in the drainfield, standing water and unusually lush vegetation are signs of poor processing inside the tank. They are another indication that the tank needs pumping, but can also indicate ruptured baffles, which is most likely if you have an older system.

Watch What You Flush

  • It's axiomatic that you should avoid putting anything in a septic system that won't decompose. Many non-biodegradable materials simply sink to the bottom and increase the sludge layer, making the need for pumping more frequent. These include:

    • plastics
    • waxes
    • pharmaceuticals
    • metals
    • paints
    • oils
    • cigarette butts
    • coffee grounds
    • or cat litter.
  • The only things that should go in the tank are wastewater and toilet paper. Household cleaning products are OK in moderation, but caustic drain cleaners should be avoided; they kill beneficial bacteria and disrupt the operation of the tank.

  • Warning

    Don't flood the tank: Large amounts of water flowing quickly into the tank from a draining bathtub or hot tub can force solid material through the outlet into the drain field. When you need to drain a large amount of water, it's best to do is slowly to give the tank time to handle it. In general, your tank will remain healthier if you conserve water.

  • A healthy septic tank contains the proper proportion of anaerobic bacteria relative to non-biodegradable material to ensure that waste material from your house gets broken down. Neither the sludge layer nor the scum layer can get too thick, or solid matter may enter the drainfield, and if that happens, the drainfield can fail. Keep your tank healthy by putting the right things into it and pumping it when the sludge layer becomes too thick.

  • You Don't Need Additives

  • Although the labels on many additives claim to make your septic system work better, they usually don't, and they may even be harmful. Certain chemicals, meant to dissolve greases and oils, can leach into the groundwater and contaminate it. The bacteria in wastewater are all the tank needs to process waste; it's better to avoid putting things into the tank that shouldn't be there than to pour in additives in an attempt to remove them.

  • About the Author

    Chris Deziel has a bachelor's degree in physics and a master's degree in humanities. Besides having an abiding interest in popular science, Deziel has been active in the building and home design trades since 1975. As a landscape builder, he helped establish two gardening companies.