Five Basic Practices to Protect Your Septic System

Around 25% of homes in Pennsylvania rely on private septic systems—sometimes called on-lot wastewater treatment systems—to manage household sewage. When operating properly, these systems efficiently remove wastewater from toilets, showers, and sinks and dispose of it in an environmentally safe manner.  But when they break down, they may pollute water resources—including drinking water—and require expensive repairs to fix. The good news is that properly installed systems can function trouble-free for many years when five basic practices are followed.

To appreciate the reasoning behind our five operation and maintenance recommendations, it's useful to know how traditional septic systems work. The most common on-lot wastewater treatment systems have just three major components: treatment tank, distribution box, and absorption area (Figure 1).

Wastewater from toilets, sinks, showers, and appliances drains into the water-tight treatment tank that’s usually buried in the yard near the home (Figure 2). This tank, which is commonly called a septic tank, traps and separates solids and scums (oils and greases) but allows liquid waste, now called effluent, to pass. Effluent flows from the septic tank through a pipe into another underground water-tight chamber called a distribution box. The D-box equally distributes effluent into perforated pipes located in the soil adsorption area where natural chemical and biological processes remove pollutants such as nitrogen and bacteria before they seep into groundwater, which, it's important to understand, may supply your, or your neighbor's, well. Gravity alone often powers water through a traditional system, but electric pumps are sometimes used. For more details on the operation of a septic system, refer to Septic System Basics.

Basic Practice 1: Be Careful What You Flush 

A traditional septic system combines simple engineering with natural biological processes to effectively purify organic waste found in domestic wastewater.  While a properly functioning system can tolerate limited amounts of food waste, soap, and detergent residue, putting anything else in your system may cause clogs or harm the good bacteria that live in the septic tank and absorption field. Table 1 lists items to avoid flushing or washing down household drains.

Items to Keep Out of Your Septic System

Chemicals that may harm beneficial bacteria inside septic tank and soil absorption area:

• Antifreeze
• Motor oil
• Bleach
• Nail polish and remover
• Drain cleaners
• Paint, stain, varnish, thinners
• Gasoline
• Pesticides
• Metal and furniture polish
• Pills and liquid medicine

Items that may quickly clog pipes:

• Bandages
• Disposable diapers, disposable wipes
• Bones
• Disposable needles
• Cigarettes, vaping cartridges
• Cat litter
• Dental floss
• Sanitary napkins

Organic waste that will prematurely fill your septic tank:

• Eggshells
• Fat, grease, cooking oil
• Food scraps*
• Pet waste

* Avoid excessive use of garbage disposal to break down food waste

Basic Practice 2: Pump Your Tank

Septic tanks prevent solid and greasy waste from clogging the distribution box and absorption field. They do this by retaining incoming wastewater long enough so solids settle to the bottom of the tank forming a sludge layer, oils jell on the surface, forming a scum layer, and bacteria digest organic material (poop!). Because these processes take time, septic tanks must reserve capacity for incoming wastewater. Without regular pumping, the sludge and scum layers can grow so large that fresh wastewater—filled with unseparated solids, scums, and fecal waste—will pass too quickly into the distribution box and absorption field, causing clogs and system failure.  

How often should you pump your tank? Every 2–3 years is commonly recommended, but households with small septic tanks, or where large families reside, may need to pump more frequently. On the other hand, homes where just one or two individuals live may be okay going with longer intervals. Instead of guessing when you should pump, it’s wise to base your decision on the recommendation of a septic system professional which is covered below in the section on inspecting your system. Be aware that many communities in Pennsylvania require septic tank pumping on a certain schedule (often every 3 years). 

If you live in a community with pumping rules, you may get a reminder from your municipality when it’s time to empty your tank. In communities without rules, it’s up to the homeowner to determine a proper pumping schedule. If you can't remember when your septic tank was last pumped (or if it was ever pumped), it’s time to contact a septic service to request an inspection of your full system. For more details on the operation of a septic system, refer to Septic Tank Pumping.

Basic Practice 3: Use Water Wisely

Most septic systems are designed to handle several hundred gallons of wastewater daily and occasional larger loads. Water overloading, which can be a serious problem, happens when wastewater capacity is exceeded. Common causes include forgetting to turn off a faucet, toilet leaks, frequent repeated clothes washing loads, multiple long showers, having extra house guests for an extended stay, or any other activities that send an unusually large load of water into your system suddenly or over an extended period. All this excess water causes liquids to pass too quickly through your septic tank, preventing the breakdown of fecal waste and the separation of solids and oils. These waste products instead flow into your absorption field, where they can cause clogs by directly plugging pipes or indirectly by creating persistently wet conditions, which cause the formation of bacterial slime layers that block water infiltration.  

Applying any of the simple water conservation practices listed below will protect your system against water overload. While some practices can take a little getting used to, in many households, they become second nature in no time. And while upgrading older appliances, such as toilets, with modern water efficient models requires upfront costs, new models usually work better and will pay for themselves by using less energy and requiring fewer repairs.

Household Water Conservation Practices to Protect Your Septic System

Adopt water conservation practices:

• Repair leaks in faucets and toilets
• Turn off the water when hand washing, brushing teeth, or shaving
• Compost food scraps instead of using the garbage disposal
• Run dishwasher and clothes washer with full loads

Install water-conserving plumbing devices, including:

• 1.6 gallon per flush (or lower) toilets
• Water saving showerheads
• Water efficient dishwasher
• Water-efficient clothes washer

Basic Practice 4: Protect Your Absorption Field

A traditional absorption field is a fragile structure of soil, sand, and gravel layers covering perforated plastic pipes (Figure 3) that are carefully arranged to distribute effluent throughout the entire bed evenly. Natural processes in the adsorption field remove pathogens and nutrients from the wastewater before the effluent soaks deeper into groundwater people may drink. We already discussed ways to protect absorption fields from clogging due to inadequate septic tank pumping and hydraulic overload.  Here are tips to protect it from physical damage and improper landscaping practices.

First, you will need to know the exact location of your absorption field to avoid harming it. If you are uncertain, you might be able to find a description or diagram with the location in documents received when you purchased your home, or you may be able to find records at your local township’s office. If neither of these methods is successful, you may need to contact a septic system inspector or installer for help locating and delineating your drain field.

After you discover where the drain field is, make sure no vehicles, tractors or other heavy equipment ever drive across it. The weight of these machines could compact the absorption area, interfering with drainage, or even break the plastic drainpipes under the surface.

Trees and shrubs should never be planted near an absorption area because their roots may plug the drainpipes and make maintenance more difficult. Turf grass is the safest plant to grow over an adsorption field because it has shallow roots (under six inches) and the only maintenance it requires is occasional cutting with a lightweight lawn mower.

Figure 3  Cross-section of a soil absorption area. The circles labeled "perforated pipe" deliver effluent from the distribution box.

Basic Practice 5: Inspect Your System 

Homeowners should routinely be on the lookout for signs their septic system may be failing. The most common indicators are listed below.

Common Indications Your Septic System may be Starting to Fail

Inside the home:

• Unusual gurgling sounds when flushing toilets or emptying sink drains
• Water backups in sinks or toilets
• Foul odors from sink drains
• Water tests that reveal high levels of nitrogen or bacteria in well water*

Outside the home:

• Spongy areas in your absorption field
• Water pooling on the surface of the absorption field
• Sewage odors near the septic tank or absorption field

* While basic water testing for nitrogen and bacteria can't confirm a failing septic system, positive tests for either should prompt an in-depth inspection of your septic system, water well, and surrounding land activities.

You should contact a plumber or septic professional if you notice any of the signs above. Your township may have a list of professional septic system inspectors, or you can view a service provider list maintained by the Pennsylvania Septage Management Association (PSMA). PSMA provides training and certification for septic system installers, inspectors, and waste haulers (pumpers). They also have educational resources to help homeowners manage their septic systems.

Pennsylvania Septage Management Association (PSMA)
P.O. Box 144
Bethlehem, PA 18016
Phone: 717-763-PSMA