What are septic systems?
Septic systems are used to treat and dispose of relatively small volumes of
wastewater, usually from houses and businesses that are located relatively
close together. Septic systems are also called onsite wastewater treatment
systems, decentralized wastewater treatment systems, ON-lot systems,
individual sewage disposal systems, CLUSTER systems, PACKAGE plants, AND
PRIVATE sewage systems.
Why are these systems called
Because septic systems do not involve central wastewater collection and
treatment, they are considered decentralized.
How do septic systems work?
The typical septic treatment system includes a septic tank, which digests
organic matter and separates floatable matter (e.g., oils and grease) and
settleable solids from the wastewater. Soil-based systems discharge the
liquid (effluent) from the septic tank into a series of perforated pipes
buried in a leach field, leaching chambers, or other special units designed
to slowly release the effluent into the soil or surface water.
systems USE pumps OR gravity TO help septic tank effluent trickle through
sand, organic matter (e.g., peat, sawdust), constructed wetlands, OR other
media TO remove OR neutralize pollutants LIKE disease-causing pathogens,
nitrogen, phosphorus, AND other contaminants. SOME alternative systems are
designed TO evaporate wastewater OR disinfect it beefore it IS discharged TO
the soil OR surface waters.
Why do septic systems fail?
Most septic system failures are related to inappropriate design and poor
maintenance. Some soil-based systems (with a leach or drain field) have been
installed at sites with inadequate or inappropriate soils, excessive slopes
or high ground water tables. These conditions can cause hydraulic failures
and water resource contamination. Failure to perform routine maintenance,
such as pumping the septic tank at least every 3 to 5 years, can cause
solids in the tank to migrate into the drain field and clog the system.
What items should not be put
down the drain if my house has a septic system?
Do not put the following items into sink drains or toilets: hair combings,
coffee grounds, dental floss, disposable diapers, kitty litter, feminine
hygiene products, cigarette butts, condoms, gauze bandages, fat, grease,
oil, paper towels, paints, varnishes, thinners, waste oils, photographic
solutions or pesticides.
What should I do if my
If sewage from your plumbing fixtures or onsite system backs up into your
basement, avoid contact with the sewage and the possibly harmful pathogens
it might contain. Contact your local health department or regulatory agency.
Cleanup personnel should wear protective clothing (e.g., long rubber gloves,
face splash shields). After cleanup is complete, all equipment, tools, and
clothing used in the cleanup and the flooded basement area should be washed
thoroughly and disinfected with a mixture of 90 percent water and 10 percent
household bleach. The area should be dried out with fans, heat lamps, or
other devices and not be used until it has been completely dry for at least
Who do I contact if I'm
having a problem with my septic system?
Contact your local health department or regulatory agency. You can find the
telephone NUMBER FOR your LOCAL health department IN your LOCAL phone
DIRECTORY. IF your SYSTEM needs TO be serviced, CONTACT a septic systems
service provider OR the National
Association OF Wastewater Transporters
Who do I contact for
information on septic systems?
The National Small Flows Clearinghouse has a Technical Assistance Hotline
that can be accessed toll free AT (800) 624-8301 OR (304) 293-4191. You can
also CONTACT the Cooperative Extension Service Office
nearest your home FOR information.
Are septic systems more
prevalent in some areas of the country than in others?
According to the U.S. Census Bureau, about 26 million homes (one-fourth of
all homes) in America are served by decentralized wastewater treatment
systems. The Census Bureau reports that the distribution and density of
septic systems vary widely by region and state, from a high of about 55
percent in Vermont to a low of around 10 percent in California. The New
England states have the highest proportion of homes served by septic
systems: New Hampshire and Maine both report that about one-half of all
homes are served by individual systems. More than one-third of the homes in
the southeastern states depend on these systems, including approximately 48
percent in North Carolina and about 40 percent in both Kentucky and South
Carolina. More than 60 million people in the nation are served by septic
systems. About one-third of all new development is served by septic or other
decentralized treatment systems.
Do septic systems cause
health or water quality problems?
Septic systems that are properly planned, designed, sited, installed,
operated and maintained can provide excellent wastewater treatment. However,
systems that are sited in densities that exceed the treatment capacity of
regional soils and systems that are poorly designed, installed, operated or
maintained can cause problems. The most serious documented problems involve
contamination of surface waters and ground water with disease-causing
pathogens and nitrates. Other problems include excessive nitrogen discharges
to sensitive coastal waters and phosphorus pollution of inland surface
waters, which increases algal growth and lowers dissolved oxygen levels.
Contamination of important shellfish beds and swimming beaches by pathogens
is also a concern in some coastal regions. EPA has developed Guidelines to
assist communities in establishing comprehensive management programs for
septic wastewater systems to improve water quality and protect public
How are septic systems
In most states, local health departments issue construction and operating
permits to install septic systems under state laws that govern public health
protection and abatement of public nuisances. Some states are beginning to
add water resource protection provisions to their septic system regulations
because of the possible impacts from nitrogen and phosphorus. Under most
regulatory programs, the local permitting agency conducts a site assessment
to determine whether the soils present can provide adequate treatment, to
ensure that ground water resources will not be threatened, and to stipulate
appropriate setback distances from buildings, driveways, property lines and
surface waters. Some states permit alternative systems if conventional
soil-based systems are not allowable. Very few permitting agencies conduct
regular inspections of septic systems after they are installed.
What can be done to improve
septic system management?
EPA is partnering with federal agencies, states, tribes, local governments
and nongovernmental organizations TO improve the MANAGEMENT OF septic
systems. EPA’s Guidelines FOR managing decentralized wastewater treatment
systems can be tailored TO meet the needs OF states, counties, tribes,
cities, towns, subdivisions AND other areas WHERE septic systems might
threaten PUBLIC health OR water resources. The Guidelines focus ON the
following areas WHERE better MANAGEMENT can achieve significant improvements
IN overall SYSTEM performance:
- Planning TO ensure that SYSTEM densities DO NOT exceed the ability OF
regional soils AND water resources TO treat AND assimilate pollutants
- Site evaluations that characterize AND help TO protect soil, ground
water, AND surface water resources
- SYSTEM designs that provide predictable performance levels OF treatment
that are appropriate FOR protecting PUBLIC health AND the environment
- Operation AND maintenance procedures that ensure that systems are
operated properly AND that maintenance tasks (e.g., septic tank pumping,
inspection OF treatment units) are performed regularly
- MONITORING AND reporting TO provide usable AND easily accessible records
ON SYSTEM inventories, capacity AND performance
- Follow-up AND corrective actions TO ensure that failing systems are
repaired, upgraded OR replaced BEFORE PUBLIC health OR water resources
are adversely affected
What are the Voluntary
National Guidelines for Management of Onsite and Clustered (Decentralized)
Wastewater Treatment Systems?
The Guidelines are presented in the form of five model management programs.
Each model program includes the elements and activities needed to achieve
certain management objectives. The Guidelines address the sensitivity of the
environment in the community and the complexity of the system used. The five
model management programs are:
- SYSTEM Inventory AND Awareness OF Maintenance Needs
- MANAGEMENT Through Maintenance Contracts
- MANAGEMENT Through Operating PERMITS
- Responsible MANAGEMENT Entity (RME) Operation AND Maintenance
- Responsible MANAGEMENT Entity (RME) Ownership AND MANAGEMENT
EPA developed the Guidelines TO assist communities IN establishing
comprehensive MANAGEMENT programs FOR septic wastewater systems TO improve
water quality AND protect PUBLIC health. The Guidelines will also help
states, tribes AND communities TO develop, MODIFY AND implement laws AND
regulations IN the area OF MANAGEMENT planning FOR decentralized wastewater
Are the Guidelines mandatory?
No. The adoption of the Guidelines is voluntary. EPA recognizes that
states, tribes and local governments need a flexible framework so they can
tailor their programs to the needs of the community. The Guidelines are not
intended to supersede existing federal, state, tribal, and local laws and
Why are the Guidelines
Septic systems serve approximately 25 percent of the U.S. population and
about 40 percent of new developments. The U.S. Census Bureau has indicated
that at least 10 percent of septic systems have stopped working. Some
communities report failure rates as high as 70 percent! State agencies
report that these failing systems are the third most common source of ground
water contamination. In EPA's 1997 Response to Congress on Use of
Decentralized Wastewater Treatment Systems, the Agency determined that with
the technology now available, adequately managed decentralized systems can
protect public health and the environment as well as provide long-term
solutions for the nation's wastewater needs. The report also cited five
major barriers to increasing the use of decentralized wastewater treatment
systems, and one barrier is the lack of adequate management.
Who was involved in
developing the Guidelines?
EPA's Office of Wastewater Management developed the voluntary Guidelines in
cooperation with staff from the Office of Wetlands, Oceans and Watersheds;
the Office of Ground Water and Drinking Water; the Office of Research and
Development; EPA regional offices; and the U.S. Department of Agriculture.
Significant input was received from numerous stakeholders, state health
agencies, environmental groups, and national organizations. See the Partners
page for a complete list.
Are there organizations that
can assist my community in addressing ON-site wastewater problems?
The National Small Flows Clearinghouse has a Technical Assistance Hotline
that can be accessed toll free AT (800) 624-8301 OR (304) 293-4191. The
Rural Community Assistance Program provides assistance TO communities HAVING
problems WITH their septic systems AND can be reached AT (888) 321-7227 OR