In a perfect world, a septic system would be a balanced, organic ecosystem that relies on gravity and bacteria to render your home’s sewage harmless as it disappears underground. Unfortunately, the world, and the average septic system, can be a messy place that’s seldom perfect.
Some septic systems fail because they are poorly designed or inadequate for a home’s sewage production. For example, the soil drains poorly, the water table is too high or you add two bathrooms and eight kids to your house.
But systems usually stink because they are misunderstood and unwittingly abused. Luckily, if you learn how your system works and treat it right, it can last a lifetime without soggy turf, smelly air or dreaded backups.
Considering the cost, nuisance and environmental damage that a wrecked septic system can inflict, this is one biology lab you can’t afford to flunk. So follow these guidelines to keep your system running smoothly.
Anatomy
Residential septic systems typically have two major components:
1. The tank, usually concrete, holds sewage and allows solids to settle and partially decompose. A residential tank usually holds 1,000 to 1,500 gallons or several days worth of wastewater. This gives most of the solids time to sink, where anaerobic bacteria digest the organic matter for several weeks.
The tank holds three layers of waste material: A scum layer of grease, fat, soap and oil that forms along the top, an effluent layer of bacteria-laden liquid that collects in the middle and a layer of solids that settle on the bottom.
2. A porous leach field allows effluent containing small solids to seep into the soil, which further decomposes harmful pathogens and poisons before it reaches the groundwater that feeds lakes, rivers and drinking wells. The field has two parts: The pipes or tile and crushed rock that carry and disperse the wastewater and the anaerobic bacteria that form beneath them. This breaks down the residual organic solids that escape the tank.
Common ailments
Sewage processing is like making wine: It can’t be rushed. If too much liquid flows into your septic tank too fast, the solids may not have time to settle. That can clog the outflow filter where wastewater leaves the tank, or even worse, it can overflow the baffle and plug and waterlog the leach field, which can cost upwards of $15,000 to repair. The simple solution is to minimize the liquid that enters your septic tank and install an effective outflow filter to trap solids.
It’s also important to understand that septic systems rely on the basic organic chemistry of bacteria decomposing organic material. If you introduce chemicals that discourage the natural decomposition process, organic solids will accumulate in the tank, displace liquids and overpower the leach field. Common culprits include large amounts of chlorine bleach, harsh cleansers and anti-bacterial products.
Because inorganic solids don’t decompose and some organic solids don’t break down fast enough, they can accumulate in the tank over time and must be pumped out. (Some building codes dictate how often this should be done.)
However, pumping a septic system too often can also cause damage. It takes six to eight weeks to restore the natural anaerobic bacterial process after pumping, but the tank can refill with liquid in as little as two weeks. This means the effluent that drains into the leach field will contain more solids for weeks, which can stress or even clog the field.
Potential cures
Many products claim to fix compromised septic systems or to keep sound ones healthy. They fall into two groups: passive enzymes that increase the sewage-eating anaerobic bacteria population, and active aeration systems that pump oxygen into the tank and foster decomposition by aerobic bacteria.
Passive residential septic systems typically rely on an anaerobic (oxygen-free) bacterial process, whereas municipal sewage-treatment plants that process large amounts of sewage depend on aeration to enhance the decomposition process.
You can put this same process to work at home by using the Aero-Stream Remediator system (about $1,100). By speeding the digestion of organic material in the tank, the pump makes the effluent that flows into the leach field up to 80 percent cleaner, according to the manufacturer. Enzyme treatments must also be added periodically. To restore a problematic septic system, the manufacturer recommends operating the Aero-Stream system for 12 to 18 months and then repeating a few years later for maintenance.
The Aero-Stream Remediator system is just one of many products available for residential use. See SOURCES for links to various products and lots of in-depth information about septic systems.
Sources
Aero-Stream
BioWorld (septic tank treatment products)
Echochem (EC-7003 septic tank and drain field treatment)
Eco-Nomic (information on how to build a septic system)
FBK Products LLC (septic treatment products)
InspectAPedia (directory of alternative septic-system designs and products)
National Environmental Services Center (information on septic systems)
Natural Environmental Systems LLC (Natural Enviro 2000)
NewTechBio (NT-Max Industrial Strength Septic Tank Treatment)
Septal (septic tank activator)
Septic Savior
Solutions Unlimited (Flush-It Septic Energizer)
UltraClear Septic Treatment
University of Florida IFAS Extension (information on septic systems)