About Septic System Alternatives

On-site septic systems are designed to provide wastewater treatment in rural and suburban areas where homes are not connected to public sewage treatment facilities. Septic systems make wastewater safe to return to the environment. Although in the past the typical septic system was comprised of an anaerobic septic tank and a drain field, today there are a number of different types of septic systems available to homeowners.

Cesspool

The most primitive form of sewage disposal is a cesspool. A cesspool can be any pit or container that receives wastewater from a house or building. The difference between cesspools and modern septic systems is that cesspools simply store wastewater; they do not treat wastewater or make it safe. For this reason, cesspools are considered environmentally hazardous and are now illegal in some states.

Anaerobic Tank with Drain Field

Traditional septic systems contain both an anaerobic septic tank, where solids are removed from wastewater and the process of treatment begins, and a drain field, where partially-treated wastewater is pumped into an area of soil through a series of perforated pipes for final treatment. These systems are relatively inexpensive to operate, and do not require electricity to operate. However, they are susceptible to a number of problems, including the build-up of sludge, clogs due to an excess of inorganic material, and problems with root clogs or ineffective soil absorption in the drain field.

Aerobic Tank with Drain Field

Aerobic septic tanks use an aerator to pump oxygen into the septic tank, and are therefore able to support aerobic bacteria. Aerobic systems are capable of more fully treating waste water than anaerobic systems. This can help to extend the life of the drain field, and may also reduce the size a drain field needs to be in order to effectively treat wastewater. The Food and Agriculture Organization of the United Nations has also found that aerobic bacteria are more able to withstand the effects of many household chemicals. On the other hand, aerobic systems are generally more expensive to maintain, both because they require more routine maintenance, and because they require electricity to function.

Pumps Vs. Gravity

Some septic systems rely on gravity to move effluent from the septic tank and into the drain field. Other systems contain an effluent pump. Homeowners whose drain fields are upslope from the septic tank or the home should consider a septic tank with a pump. Because they contain working mechanical parts, tanks with pump may experience more frequent malfunctions than tanks without pumps. However, a tank with an effluent pump will ensure that wastewater is evenly spread throughout the drain field, and by doing so will help to preserve the life of the septic system.

Stand-Alone Aerobic Tanks

There are some aerobic septic tanks on the market that aim to completely treat wastewater without the need for a drain field. In some cases, these systems double as lawn care, because the treated effluent may be used to directly water the lawn. The advantages of these are that they save space and avoid many of the problems and repairs associated with drain fields. Otherwise, the pros and cons are similar to those of other aerobic septic tanks.

References

• Pipeline: Home Aerobic Wastewater Treatment
• Food and Agriculture Organization of the United Nations: Aerobic Versus Anaerobic Wastewater Treatment
• Environmental Protection Agency: A Homeowner's Guide to Septic Systems
• Septic Plus: Pressure System with Pressure Mound
• Northern Purification Systems: Clearwater Owner's Manual