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SEPTIC TANKS
Water pollution from malfunctioning septic systems is a major problem. The U.S. Environmental Protection Agency reports that septic systems are the most frequent sources of groundwater contamination.
Septic systems, when properly designed, installed, and maintained can provide cost-effective treatment of household sewage and many years of dependable service with little adverse impact on the environment.
Because septic systems are underground, they are often forgotten or ignored by homeowners. Problems arise when people neglect normal maintenance procedures.
When a septic system malfunctions, it loses the ability to remove pollutants and disease-carrying microorganisms from wastewater. The virtually untreated water pollutes groundwater and deep wells which we use for drinking water and other household needs. Surface waters, nearshore areas, streams, and estuaries may also be contaminated from leaking systems.
When your septic system fails, you also face plumbing backs ups, overflows, expensive repair costs and very serious potential threats to human health. Our domestic wastewater contains bacteria and viruses that cause hepatitis, dysentery, and other gastrointestinal infections. Although typhoid fever rarely occurs in the U.S., it can be transmitted through sewage.
Responsible Use and Maintenance of a Septic System
Caring for your septic system will minimize potential problems. Responsible use and maintenance will keep your septic system operating smoothly and help prolong the life of the system. Remember: whatever is rinsed down the kitchen sink or flushed down the toilet ultimately makes its way into the soil and groundwater or remains in the septic tank until the tank is pumped.
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Know the location of all parts of the septic system. Check your septic tank for accumulation of sludge and surface scum on an annual basis. Most state certified, licensed septic companies will do a free inspection as a courtesy service. If the bottom of the surface scum is within three inches of the tank's outlet pipe, the tank needs to be pumped and cleaned.
A reputable contractor should remove sludge and scum every three to five years, although the intervals vary depending on the system's frequency of use and some systems may operate satisfactorily for a longer period of time. Removing sludge and scum ensures an adequate volume of wastewater in the tank and prevents solids from washing out into the soil absorption system where they could clog the soil absorption field.
- Keep the septic tank and adjacent soil absorption area clear of heavy vehicles which could compact the soil or collapse the drain lines. No structures should ever by built over the septic system. The drainfield needs to "breathe" and should not be covered by any hard surface such as a patio, tennis court, or driveway
Do not plant trees or shrubs near the system as roots can work their way inside pipes and clog the drain lines. The yard space above the drainfield should be maintained with healthy grass and native plants.
The following substances should NOT be disposed of in home plumbing:
cigarettes,
facial tissue,
feminine hygiene products,
paper towels,
disposable diapers,
condoms,
dental floss,
cat box litter,
coffee grounds,
grease and
other organic waste.
Disposal of these items adds to the solids load, fills the tank more rapidly, and decreases its efficiency.
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Be aware that some species of grass can create a problem by growing as a mat and effectively sealing the drainfield so it cannot breathe.
- Do not use septic tank additives or cleaning compounds which are promoted by manufacturers to aid biological decomposition in the tank or eliminate the need for sludge to be removed.
Yeast, bacteria, and enzyme additives and chemical treatments are unnecessary, and there is no evidence that they improve the system or prevent system failure. Using these products may cause the tank to work less efficiently, damage the drainfield, and may contaminate groundwater and drinking water drawn from area wells.
- Minimize or eliminate the use of the kitchen garbage disposal. Using a garbage disposal can increase the solids load to the septic tank by as much as 50%. Never pour grease, cooking oils, fats, or gristle down the sink drain or through the garbage disposal. Dispose of grease by absorbing it in paper and putting it in the garbage for sanitary landfill collection.
Successive deposits of solidified fats will build up and obstruct parts of the system. Organic garbage such as vegetable pieces and fruit peelings can also burden a system. These materials should be put in a compost pile or set out for curbside garbage pick up. A kitchen sink strainer also helps reduce the amount of food waste entering the septic tank.
Burdening a system incurs more frequent servicing and increases maintenance and repair costs. Limit solids, such as food scraps in the kitchen and paper products in the bathroom.
- Do not pour common household chemical down the kitchen sink or toilet. Avoid using strong detergents, solvents, and disinfectants. They can destroy the beneficial bacteria which are actively decomposing sewage and are essential for the septic system to function properly.
Drainfield failures may be related to reduced bacterial activity as a result of continued, frequent use of strong chemicals such as bleach, lye, and drain-cleaning solutions of sodium hydroxide.
Minimal use of household cleaning agents such as mild detergents, soaps, and bleaches should not harm a system. Dump cleaning water in the yard, not down the sink. Avoid using water fresheners and strong chemicals in the toilets, and, whenever possible, use toilet paper that has not been bleached, dyed, or perfumed.
- Use phosphate-free laundry and dishwashing detergents, biodegradable cleaning products, and natural substitutes that will not damage the septic system. Low phosphate products will cut down on the influx of nutrients which contribute to algal blooms and oxygen depletion in area waters and other serious water quality problems.
Strong chemicals not only kill the bacteria necessary for the health of the system, but they also create the added risk of leaching into underground water sources and contaminating wells and groudwater.
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- When building a new home and installing a septic system have a state certified, licensed contractor evaluate the site and provide an explanation of such factors as soil permeability, water table elevation, and the size of the drainfield.
- Never burn or bury unused chemicals or their containers.
Failures resulting from construction problems usually appear right away. Broken or disconnected pipes, a tilted distribution box, smeared trench walls, or the use of unsuitable filter media such as unwashed gravel in the trenches, will cause effluent to rise and pond shortly after your family begins occupancy.
- Older homes may be equipped with smaller septic systems which simply cannot handle the large amounts of water modern appliances use. Running a garbage disposal, dishwasher, and washing machine, can involve such a heavy increase in use of household water that the drainfield becomes saturated and forces water to the soil surface.
When you remodel your home, add a new addition, or increase your family size, evaluate your septic system; it may need to be enlarged.
- Direct rain runoff from roof downspout and foundation drains away from the septic system and drainfield to avoid saturating the soil. Refrain from watering the lawn or vegetation over the drainfield. This area already receives all the water it needs.
- Conserve water. Water flow to the septic system can be substantially lowered through water conservation. Leaking faucets and toilet tanks can eventually saturate the soil absorption field. For more information on steps you can take to save water, refer to the following section, Water Conservation in the Home.
Signs of Septic System Failure
Very specific signs indicate problems or potential problems within a septic system. The minor, nuisance problem a homeowner lives with today can build into a problem of major proportions over time, if ignored. Discovering a problem and correcting it before it becomes serious makes for an easier solution.
Homeowners should be particularly aware of the following warning signs:
- Sluggish flow from the drains in the house and sluggish toilet flushes accompanied by gurgling sounds in the plumbing. Do sinks seem to take longer to empty? Does the shower stall fill up with water? Are all the drains in the house slow or jut one? If only one drain or room is affected, a single clogged pipe inside the home may be responsible. However, if all kitchen and bathroom drains are slow, the problem is likely to be within the septic system.
- Patches of lush, green grass in the yard indicate the system is allowing effluent to rise near the surface.
Noticeable odors inside or outside the house and plumbing backups indicate septic system problems.
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- Effluent rising to the ground. Wastewater seeping up onto the lawn and forming puddles is very serious, because children might play in them by mistake. Effluent rising from trenches will appear as a gray-black liquid flowing across the ground or into a low spot or roadside drainage ditch. The liquid will be clearly visible and have an unpleasant smell.
- Ground which is soft and spongy underfoot and the appearance of low spots or depressions in the soil indicate that there is poor drainage and the soil is becoming saturated. Poor drainage due to an undersize or improperly installed system, one located in the wrong kind of soil, or a drastic increase in water use may be responsible for drainfield failure.
- One final note: high water tables can impede drainage. If the groundwater moves into the soil absorption system, effluent can be forced up towards the ground surface before pollutants and organisms are removed, or the wastewater can be carried along with the groundwater and travel long distances from the absorption area. It is essential that a sufficient depth of soil exists between the bottom of the drainfield trench and the seasonal high water table.
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