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An on-site septic (sewage) system is the most common method of sewage treatment and
disposal for homes that are not on a public sewer line. A septic system consists of a tank
and a drainfield where the wastewater slowly seeps into the soil. Proper septic systems
treat the sewage before it reaches ground and surface waters. Poorly designed or
malfunctioning systems cause odor and water pollution.
A licensed designer must be consulted about new or
upgraded systems. Your county health department must inspect it before you cover it. This
is the law.
Be sure you know how your system works. Many newer homes have
"alternative" systems with electric pumps and controls which require annual
inspection by a professional. The state Department of Health has information about the
different types of systems and their maintenance.
Septic tanks need to be inspected by a knowledgeable person once a year.
Frequency of pumping will depend on your household habits.
- Do not flush material that will not easily decompose, such as hair, diapers, cigarette
butts, sanitary napkins, tampons, or coffee grounds. They will reduce your system's
capacity and clog the drainfield.
- If you use a garbage disposal, it will contribute to the wasteload of your on-site
system and you must allow for more frequent inspection.
- Do not wash or flush strong chemicals into the system. They kill the bacteria needed to
decompose the wastes.
- Reduce the volume of wastewater by installing water-saving devices and thinking
conservation year-round, not just during drought.
- Balance water use throughout the week to avoid overloading the system at any one time.
- Don't let the soils over the drainfield get compacted. Do not use that area for large
animals, a roadway, parking spot, patio, or as a storage area.
- Do not cover the surface of the drainfield with anything impermeable like plastic or
cement. This reduces the soil's ability to "breathe," preventing proper function
of the drainfield.
- Divert roof drains and runoff away from the drainfield. Saturated soil cannot absorb
wastewater from the septic system.
- Do not drain hot tub water to septic systems or surface water; the large amount of
chlorinated water would be harmful. Regulations vary, so please check with your local
health department for disposal options in your community.
- Keep accurate records, including diagrams of design, location and size of the entire
septic system. They should include dates the system was inspected and when the tank was
pumped (a record page is included in this guide).
Signs of Septic System Failure
- Ponded water or damp spots, foul odors, and/or dark gray or black soils in your yard
- Water that rises to the surface during heavy rain or when your water use is high, such
as when doing laundry
- Toilets that flush slowly or drains that back up
- Patterns of bright lush growth in your lawn, or the growth of plants associated with
If you notice any of the above signs or have any suspicions that your system may have
problems, get it checked right away. Septic systems do not generally show signs of failure
until they are in an advanced state of deterioration. You can avoid costly repairs by
having your tank inspected and pumped regularly.
For information and help: Contact your county environmental health department or
the state Department of Health.
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