Professor and Water Quality Specialist,
Food, Agricultural and Biological Engineering
Assistant Professor and Extension Soil Scientist,
School of Natural Resources
About 1 million households in Ohio are located beyond the city sewer and must treat and dispose of wastewater on the lot. Like all of the appliances and structures in your home, sewage treatment systems require care and will eventually have to be upgraded or even replaced. Cities hire professional operators to take care of their sewage treatment systems. For homes with individual sewage treatment systems, the homeowner is responsible for providing care and maintenance.
Diagram of a septic system.
Septic systems consist of two basic parts; a septic tank and a soil absorption system. The septic tank provides a small portion of the treatment by creating a large quiet compartment to allow solid material to settle out of the wastewater and collect in the tank. Once the large solid material is settled out, the sewage follows into a deep layer of unsaturated soil where the soil and microorganisms growing in the soil remove the pollutants before the wastewater enters ground or surface water.
Septic systems are simple to operate and when properly designed, constructed, and maintained, they do an excellent job of removing pollutants from wastewater to protect Ohios water resources. Property owners must do a few important things to keep their system operating for 20 to 30 years.
Since the soil must accept all of the water used in your home, using less water is the best thing a resident can do to maintain their septic system. Water conservation includes:
The soil absorption system (or leach field) is the most important part of a septic system, so it is important to protect the area. Careful landscaping includes:
Septic tanks are installed to allow solids to settle out of sewage and hold these solids in the tank. Over the years of operating, accumulated solids begin taking up too much room in the tank, reducing the volume available for settling. When this happens, solids start escaping the tank and can clog the soil in the soil absorption field. Before this happens, the septic tank should be pumped to remove the solids.
Cross section of a septic tank.
Table 1. Estimate Septic Tank Pumping Frequencies in Years (For Year-Round Residence)
Tank Size (gal)
Household Size (Number of People)
Note: More frequent pumping needed if garbage disposal is used.
Just like the house roof, driveway, and furnace, septic systems require upgrades and possibly replacement. Expect to have to upgrade a properly designed and installed septic system every 20 to 30 years.
Standards have changed and research has developed new and better approaches to treating sewage onsite to protect the health of the residents, the community, and the environment. While some older systems may have met standards when they were installed, upgrades and replacements will take advantage of the tremendous advances scientists and engineers have developed to improve wastewater treatment. Be prepared for new or upgraded systems to be different from the system that may have been installed decades ago.
Few homeowners are prepared to operate and maintain a wastewater treatment system. Communities have always hired professional operators to run wastewater treatment plants. Some communities are now hiring operators to inspect and manage septic systems. Professional management offers many advantages for Ohio communities.
Talk to your community leaders about establishing a septic system management program, so that all of the systems in your area receive proper and regular inspection and management. To learn more about onsite wastewater management consult the OSU Extension series on Onsite Wastewater Management AEX-750 through 754. These and other wastewater treatment publications can be found at www.ag.ohio-state.edu/~setll.
Click here for the PDF version of this fact sheet.
All educational programs conducted by Ohio State University Extension are available to clientele on a nondiscriminatory basis without regard to race, color, creed, religion, sexual orientation, national origin, gender, age, disability or Vietnam-era veteran status.
Keith L. Smith, Associate Vice President for Ag. Adm. and Director, OSU Extension.
TDD No. 800-589-8292 (Ohio only) or 614-292-6181