What’s the difference in conventional vs aerobic septic systems you ask? Well the differences are many, but the Idea is the same! Both systems take raw sewage and allow for microbes and bacteria to break down solids and treat the effluent, the difference is how active the microbes are.
Conventional Septic Systems
Conventional septic systems are a simple, no moving parts operation. Older systems used one tank, while newer systems use a two tank set-up.
Tank number one, sometimes called the trash tank, is where the raw sewage enters the treatment system, in this tank the sewage is allowed to settle and have heavier solids settle to the bottom of the tank. The lighter floating solids float making a layer of scum on top of the water. The sludge and scum receive some treatment from anaerobic microbes in this first tank. The now clarified water then moves into the treatment tank where more treatment occurs. The water then moves out into the drain field, which can be a standard perforated PVC over a media bed, like gravel or chipped tires. Other drain field can be gravelless pipe or leaching chambers.
So can you use a conventional septic system? that depends on several factors. First is soil type, clay doesn’t allow for good water movement, second is restrictive horizons, if you dig down a foot and hit bedrock a conventional system isn’t right for you. Another factor is water tables in your area, again if you have ground water at 2 feet below grade, you will not be able to put more water into that already saturated ground.
The best way to go is have a site evaluator check your soil type and look at all the factors.
These two photos show the tanks, these two are square but they also come in round, they can be constructed from concrete or fiberglass or several other materials.
Here is the conventional drain field, constructed from perforated PVC pipe over a gravel media bed and covered with Geo-Textile fabric to keep soil out of the gravel.
Aerobic Septic Systems
Aerobic septic systems are the hot rods of the sewage treatment world, and as with fast cars they are pricey. Sometimes you have to have aerobic systems if your soil or other factors prohibit a conventional system.
An aerobic system is made up of three compartments, the trash tank, the treatment plant and the pump tank. Some systems are three separate tanks and some are one large unit made up of three compartments. The two system types share the first stage of settling the sewage in the first tank, the trash tank, but this is where the similarities end. As the water enters the treatment plant an aerator pumps air bubbles up thru the effluent, this injects extra oxygen into the water, much like a fish tank. All that extra oxygen makes a better environment for aerobic microbes, which work lots better and faster than their anaerobic counterparts.
You can see in the photo above the three access ports into the three different compartments of the aerobic septic system.
As the bubbles work up thru the effluent feeding the aerobic bacteria which in turn treat the waste water is is allowed to further clarify thru this tank and out into the pump tank, where it receives a last shot of chlorine to disinfect and bad pathogens. From the pump tank the now treated water is considered safe enough to be applied to surface vegetation by sprinkler heads for uptake and final treatment.
So which system is right for you? If your soil can handle a conventional system, by all means use it. An aerobic septic system will fill the gaps when soil or location are a problem.
Septic System Maintenance is a must!
Septic system maintenance is a must to avoid drain field failure. The septic tank’s purpose is to trap solids and oils, and the drain field’s purpose is to absorb waste water, the drain field is where most of the water treatment occurs in a sub surface system. If solids or oil escape from the tank and flow into the field, it will clog, fail, and overflow onto the yard.
One thing every homeowner dreads, replacing the septic system drain field. This is easily the biggest expense of septic system maintenance; it can run from $3,000 to $10,000+.
Check out Septic System Maintenance tips to help avoid the nightmare of a drain field replacement:
1) Don’t flush anything down the toilet that isn’t human waste or bathroom tissue that is approved for septic tanks. Sanitary napkins, tampons, condoms, etc: all these items end up in the septic and will last a long time, if they can’t break down, they will clog the system sooner or later. Just throw them in the trash can and save yourself major problems!
2) In Sink Garbage Disposers: Handy in the kitchen, but tough on your septic system maintenance schedule. The septic system is designed to work with a certain amount of daily waste water, when you add extra kitchen waste, the bacteria in the system has to work overtime to break down the waste, this can add to sludge issues that can build up and clog the system as it goes from the trash tank into the treatment tank and into the drain field. Do yourself a favor, use the trashcan, or better yet, compost your kitchen waste! Also avoid pouring grease or cooking oil down the sink. Doing so will gum up the drain lines as well as your septic system. You should let the oil or grease cool, pour it into a container, and put it in the trash. This will save you lots of money and headaches in the long run.
3) Harsh chemicals can kill off you bacteria that do all the work in the septic system, don’t use bleach in the washing machine or other that end up in the septic tank: your septic system relies on bacteria to break down waste. If you must use bleach, use it sparingly.
4) Keep water use low and steady: If your washing machine drains into the septic system, maintain a regular wash schedule, don’t save wash day for Saturday and do 20 loads at once. Spread the wash out over the week so that the drain lines have a steady load, too much water all at once will put extra stress on the drain field. If you have a leaky toilet or faucet, get them fixed, the drain field can only absorb so much water over a given period of time, once it’s reached, the sewage has to go somewhere…and that could be back in your house!
5) Don’t drive over or build anything over your drain field: Older drain fields were constructed from perforated plastic pipe over a bed of gravel or other similar media, newer drain fields can be made with a gravel less pipe or leaching chambers all of which can be crushed under the weight of a car or tractor, not to mention the soil, when saturated with water, can become unstable and possibly collapse under a vehicle thus wrecking your drain field. Speaking of unstable soil, try to build something over that drain field and see what type of nightmare that would be, not to mention the possible health hazards!
So there you are five steps for simple septic system maintenance that will pay off in the long run, hopefully saving you the high cost of a drain field replacement.
Remember do your septic system maintenance and do yourself a favor!
Septic system pumping may be the most important preventative maintenance step you as a homeowner can do for your septic system. Besides the obvious steps of keeping non-organic materials out of your septic system, pumping out your tanks will go along way to keep you On site sewage facility running smoothly and odor free for a long time.
Septic System Pumping, Why Do You Need It.
The need to pump out your septic system is brought on by two culprits, scum and sludge.Scum is the lighter than water sewage that gets washed onto the septic tank, grease, oil etc. Sludge is the dissolved and partially dissolved solids that settle to the bottom of the trash tank, slowly building up over time, they will stay at the bottom of the tank until they are pumped out. After a few months of use the sludge and scum accumulates in the settling tank leaving the water in the middle layer able to flow into the treatment tank. Once the bottom layer of sludge reaches the top layer of scum, no water can get thru with out carrying the scum and sludge with it.The build up of scum and sludge in your septic tanks over time diminishes the flow of effluent thru your tanks and causes slow draining issues and can even lead to sink and toilet backups. Worse yet, if the sludge and scum makes it into your drain field it can permanently clog your drain lines, causing an expensive repair of your drain field, maybe even moving it all together. This can also cause waste water to back up out of your septic tanks and contaminate the local environment and ground water in the area. Raw sewage is not something to take lightly, it can cause serious health risks. Think of it this way, would you want your children or grandchildren playing around a sewage spill?
Septic System Pumping: When Do You Need It?
The need for septic system pumping depends on several factors, some of the factors include Septic Tank size, number of occupants in the residence, the use of in sink garbage disposers will increase solid waste in the tanks and therefore increase the need for septic system pumping. A new idea in garbage disposers is an enzyme injector that gives the septic system a boost to compensate for the extra load of solid waste material. In most cases, with normal use, septic system pumping should occur every one to three years, of course your mileage may vary. Of course you could always have your system pumped out on a normal schedule, and not wait for excess build up , say every year at the same time, like changing the battery of your smoke detectors. Some will say that this is overkill and a waste of money, although it will certainly be cheaper than replacing a drain field. But by all means if you ever notice a slow drain time, or toilets backing up I would have someone come and check out the system before expensive damage occurs.
So What’s the Cost For Septic System Pumping?
This is another area that you will need to shop around, If you were to get an inspection along with the tank pumping you should expect to pay a little more. A ball park figure to start with will be around $100 and up from there,If they have to dig to get access to your tank, expect to pay more. Make sure the service you use is licensed thru the local permitting authority, you don’t want an unskilled or sloppy work around your house with the like of raw sewage possibly contaminating your land. As the old saying goes, you get what you pay for.