Septic System Maintenance

AEX-740
Agriculture and Natural Resources
Date: 
03/02/2016
Karen Mancl, Professor, Food, Agricultural and Biological Engineering
Brian Slater, Associate Professor, Environment and Natural Resources

A home beyond the reach of a city sewer must have wastewater treated and dispersed on the lot. Like all the other components of a home, the household sewage treatment system requires care and regular maintenance. A neglected system threatens the health of the residents and visitors, and results in financial losses in the investment in the system and the property. In a city, a trained professional operator cares for the wastewater treatment system. For homes with household sewage treatment systems, the property owner is responsible for maintenance.

Septic systems have three basic parts: a septic tank, a treatment system and a dispersal system. Because many of a septic system’s components are buried, property owners often do not know what type of water treatment system they have, nor do they know how to care for it.

This fact sheet presents the basic, regular maintenance required for all types of systems. Specific, detailed information for an advanced treatment system or a complicated dispersal system can be obtained from the system installer or the local health department.

The expected life of a properly maintained wastewater treatment system is 20 and sometimes up to 30 years. Systems that old or older may be too small to deal with current wastewater volumes, or some of the tanks or other components may have deteriorated and may need to be replaced.

A property owner should do three things to ensure trouble-free system performance: conserve water, landscape carefully and pump the septic tank.

Conserve Water

Excess water taxes all wastewater treatment systems. Systems are designed to handle up to 50 gallons per person per day of household sewage. A home-based business that uses a lot of water or pours excess chemicals, grease or cleaning agents down the drain can overwhelm a household sewage treatment system. Using less water benefits all systems, so water conservation is a good investment.

Repair water leaks such as dripping faucets and toilet valves that don’t seal.

Install water-conserving fixtures such as low-flow showerheads, low-flow toilets and a front-loading washing machine.

Space out water use throughout the day and the week. Avoid washing several batches of laundry on one day. Coordinate with family members to space out bathing throughout the morning and evening.

Landscape Carefully

Since a household sewage treatment system is buried in the yard of the home, even seemingly innocent landscape changes can damage the septic system. Mark the system location and be careful when making lot improvements.

Extra water can drain onto the system from other areas of the lot. Downspouts, paved areas and slopes on the lot can all deliver extra water to the area where the wastewater is being treated and dispersed. A typical septic system applies about 100 inches of extra water per year to a yard. This is on top of the approximately 40 inches per year of normal precipitation. Adding extra drainage water can cause a system to malfunction.

Avoid soil compaction caused by parking vehicles or operating heavy equipment in the soil dispersal area. The soil must allow infiltration of a significant volume of water, so compaction is a serious problem. Less water can move through compacted soil when larger soil pores are closed up.

Do not cover up any part of the system, because it limits access for maintenance and repair. Never allow pavement, decks, above-ground pools and out-buildings to be placed on top of the system.

Do not place any additional soil fill over the system. Many of the system components are meant to be shallow to allow for air infiltration. If sewage is surfacing in the yard, covering it with fill does not work to solve the problem; instead, doing so makes the situation worse. Surfacing sewage is a sign that the system is malfunctioning and needs to be repaired or replaced.

Pump the Septic Tank

To protect other treatment system components and to stop the soil from clogging, septic tanks are installed to separate and store solids from the sewage. Septic tanks are just a part of a larger sewage treatment system and need regular maintenance to protect the investment in the overall treatment system. If not pumped on a regular basis, solids will overflow and escape, causing system damage. Waiting for a backup is much too late, as the damage is already done. Solids need to be removed before the tank starts to overflow. Table 1 presents the estimated time for septic tank pumping for different sized tanks and families.

Do not use biological or chemical additives in place of tank pumping. Sewage has adequate bacteria and enzymes, so additives are unnecessary.

Do not use a garbage disposal in a home with a septic system. The extra solids fill up the tank, increasing the cost and frequency of maintenance.

Baffles and filters are important components of a septic tank designed to improve the removal and retention of solids. When the tank is pumped, make sure the condition of the baffles is checked. The baffles can crumble or fall off with time, or they can be accidentally damaged during pumping. Most septic tanks are now equipped with an effluent filter to help capture and retain solids. These filters do a great job of protecting the treatment system, but they do require cleaning. Filters in a lightly used system should be checked once a year and washed before replacement. A filter in a heavily used system may need to be cleaned every six months.

Never enter a septic tank! Any work or repairs should be made from the outside. The septic tank, even when empty, can produce toxic gases that can kill a person in a matter of minutes. Never enter a tank to retrieve a person who has accidentally fallen in. Call 911, then put a fan on top of the tank to blow in fresh air.

Baffles from the tank openings to the ground surface make future maintenance easier. However, the lids can crack or leak. Protect the tank lid from mower damage, and replace broken lids. Always secure the lids to keep children and pets from accessing the tank.

Professional Management

Few property owners are prepared to operate and maintain a sewage treatment system. Some household sewage treatment systems have mechanical components, so a professional service provider is required. In Ohio, these service providers are registered with the local health department and must participate in continuing education every year. The service fees they charge are well worth the benefit of protecting the health of the residents and protecting the investment in the treatment system. For most household sewage treatment systems, an annual inspection and a small amount of maintenance can avoid a total system failure that would necessitate expensive and inconvenient system replacement.

Table 1. Estimated septic tank pumping frequency (in years) for different size tanks for 1 to 9 people in a household of year-round residence.
Note: If a garbage disposal is used, more frequent pumping is required. 
Tank Size
(in gallons)
Number of People
1 2 3 4 5 6 7 8 9
500 5.8 2.6 1.5 1 0.7 0.4 0.3 0.2 0.1
750 9.1 4.2 2.6 1.8 1.3 1 0.7 0.6 0.4
1,000 12.4 5.9 3.7 2.6 2.0 1.5 1.2 1 0.8
1,500 18.9 9.1 5.9 4.2 3.3 2.6 2.1 1.8 1.5
2,000 25.4 12.4 8 5.9 4.5 3.7 3.1 2.6 2.2
2,500 31.9 15.6 10.2 7.5 5.9 4.8 4.4 4 3.0
Cross Section of a Septic Tank
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