The septic tank serves as a settling basin where solids accumulate and are gradually broken down by bacterial action.
Some of the solid waste is actually liquefied by this "natural bacterial decomposition," however the rest of the waste accumulates in the bottom as a layer of sludge. Additionally, a small percentage of this waste (mostly fats and oils) float to the top of the tank to form a layer of semi-solid scum.
The population living in metropolitan areas (who have never had the pleasure of maintaining a septic system, or who have never experienced waddling in their leachfield or drainage field, or have never had to pump out their septic tank)......those people simply flush their toilets and "away go troubles down the drain." At least that's how the advertising jingle goes.
Those of us living in more rural areas have been forced to learn about the maintenance and working of the sewage treatment facility attached to our home, "the septic system." Usually a septic tank is connected to a drainage field or seepage pit of some kind. If properly maintained, a well-designed system will last almost indefinitely. However, if it is neglected for an extended period of time, it can back up and clog the drainage field. This neglect can result in an expensive excavation and even a replacement of the drain pipes that could cost thousands of dollars.
Although designs vary, most septic tanks consist of a watertight, below ground, tank that should have one or two manhole covers (buried below ground) to provide access for cleaning and inspection. Sewage from the house flows into the tank through an inlet pipe near the top on one side. It flows out through a discharge or overflow pipe at the other side. The pipe may end in a large tee fitting or into a baffle (wall) preventing the effluent from flowing straight across the tank from one pipe to the other.
The incoming sewage will be diverted downward with a minimum of splashing, allowing the solids to sink to the bottom.
Outgoing effluent is drawn from below the top layer of the floating waste (grease, oil, and scum) so that only liquid waste or solids that have been liquefied by the bacterial action going on at the bottom of the septic tank are discharged out into the drainage field. We'll talk more about the importance of live bacteria later in our Septic Systems 101 class.
A typical household sewage treatment system consists of a house sewer, septic tank, distribution box and absorption field or seepage pit. In some cases there are pump tanks, aerators and special valve assemblies.
House Sewer - The pipeline connecting the house to the septic tank.
Septic Tank - Untreated liquid household wastes (sewage) will quickly clog your absorption field if not properly treated before it gets there, and the septic tank provides this needed treatment. When sewage coming from the house enters the septic tank, the heavy solids settle to the bottom of the tank; the lighter solids, fats and greases partially decompose and rise to the surface and form a layer of scum. The solids that have settled to the bottom are attacked by bacteria and form sludge. Septic tanks do not remove bacteria and, therefore, the effluent that is discharged cannot be considered safe.
Distribution Box - This serves to evenly distribute the flow of effluent from the septic tank to the drainage field, absorption field or seepage pits. The distribution box prevents overloading of one part of the system by making sure the that each trench or pit receives an equal amount of flow.
Absorption / Drainage Field - A system of narrow trenches partially filled with a bed of washed gravel or crushed stone into which perforated or open joint pipe is placed. The discharge from the septic tank is distributed through these pipes into trenches and surrounding soil. The subsurface absorption field must be properly sized and constructed.
Cesspools (see Diagram 2) -These work in a similar manner to septic systems. Sewage water usually seeps through the open bottom and portholes in the sides of the walls. These can also clog up with overuse and the introduction of detergents and other material which inhibit the bacterial action. When a sewage backup occurs, homeowners usually have the system pumped out. Pumping out will only relieve the system temporarily. The clogged pores in the ground, called a bio-mat, remain and eventually the system will have to be pumped again and again.
An alternative to the typical absorption system is the sand mound. Sand mound systems are used in areas where the site is not suitable for a traditional (in-ground) septic system. The soil may percolate too slowly, or the water table may be too high. As you can see from the diagram below, the wastewater flows to the typical septic tank(s), but then is pumped to a distribution network instead of an in-ground drainfield. The distribution network is in a bed of sand that is over the top of the ground. The mound is then covered with a fabric and then topsoil. Sand mounds are more expensive to install than traditional in-ground septic systems. Lower cost sand mounds are approximately $15,000-$25,000.
Since solids will continue to build up at the bottom of the tank, it is imperative that the septic tank be pumped out periodically. Remember, sludge is not biodegradable; if it's not pumped out, sludge will accumulate until it overflows the tank.
It is important to get the septic tank cleaned before the sludge level gets high enough so that the solid material at the bottom, or the semi-solid scum at the top, can flow out into the drainage field. This will quickly clog the drainage pipes and the soil into which they drain.
The frequency of cleanings will depend primarily on the amount of wastewater that goes through the system each day. The frequency also depends on how careful you are about not throwing excess fats, rinds and other similar garbage down the drains. The more solid waste thrown into the system, the quicker the tank will fill up. Heavy flows of water also tend to make the tank fill up more quickly. That is why it is best not to use a garbage disposal when you have a septic tank, and why water should not be left running indiscriminately in sinks or toilets.
There must be live bacteria in every septic system at all times - their job is to digest all organic waste matter in the system. If if there is no bacteria in your system, it will simply act as a holding tank for your waste. The tank will quickly become full because no natural digestion is occurring - and that's when septic systems back up.
Bacteria are killed off or overrun for the following reasons:
Enzymes are a catalyst for bacteria; enzymes themselves do not digest anything. So beware: if you do not already have live bacteria in your system, adding enzymes will not help. If there is no bacteria in your system, there is no reason to waste money adding enzymes.
Live bacteria is a critically important component of a healthy and properly functioning septic system. Not just any bacteria will do - call us at All-American Serptic Service and we will add adult live bacteria that are "FACULTATIVE," meaning they will work with or without the presence of oxygen.
A facultative bacteria is one that would be useful in situations that have air and also in situations where there is no air (anaerobic situations). The bottom of the septic tank has no oxygen and therefore needs anaerobic bacteria.
Pro-Pump Hi-Count Live Bacteria liquid live adult bacterial cultures are both "facultative" and "anaerobic." Ecological Laboratories, the manufacturer of Pro-Pump Hi-Count Live Bacteria, has have been producing this strain of "friendly bacteria" for over 21 years, and they are the only commercial manufacturer of this thiobacillus (purple strain) bacteria today. For more information about Pro-Pump Hi-Count Live Bacteria, visit the Products page of our All-American Septic Service website.
This commercial strength "facultative" bacteria:
The bacterial populations have been determined by repetitive plate count to be in excess of 350 million organisms per milliliter.
What makes Pro-Pump Hi-Count Live Bacteria so unique is that the adult bacteria in the jug are dormant and remain that way until it is poured into your system, then these adult live "facultative" bacteria will immediately revive and begin feeding and reproducing while attacking the organic waste matter in your pipes, septic tanks and leachfields.
For more information about Pro-Pump Hi-Count Live Bacteria, visit the Products page of this website.
As communities grow more crowded and awareness of the impact of one home upon another, regulatory authorities have begun to pay more attention to proper maintenance of each individual property.
One factor under scrutiny is the septic system. Rather than leave it up to the homeowner to decide how often to clean and pump a system, a growing number of municipalities are imposing requirements. In addition, state laws are becoming more stringent. If an existing system fails, or in the building of new homes, some states have begun imposing tighter regulations on the types of systems allowed.
Nationwide about 25% of all homes rely on a septic system. With so many systems in constant use and most of them older models of inferior design, fear has been mounting that improperly maintained systems could pollute ground-water supplies or that the health of ones own family could be jeopardized.
The best way to avoid major repairs or replacement, or to avoid being fined for operating a substandard system is to call us at All-American Septic Service. Here's what we can do: