Homeowners are responsible for maintaining their septic systems. It not only protects the investment in your home, but also protects your water supply and those of your neighbors. You don’t want to be the cause of major ground water or surface water contamination because of a malfunctioning septic tank. The liabilities are potentially huge and your homeowners insurance may not cover you if you didn’t do the required maintenance. It will also make selling your home difficult, I personally have walked away from houses I wanted to buy because the septic system was not in proper working order.
Septic tank management can be very simple. If the tank has been properly constructed and installed very few interventions will be necessary and the interventions will primarily be inspections. The major components of a septic system are a collection pipe from the house, the holding tank, and the drainage system (usually a field). The collection pipe is the final pipe leaving the home that contains all the household waste water. This part of the system is identical for people connected to a municipal sewer except for where the pipe goes.
The septic tank is a storage tank to separate out solids from the waste water. They are watertight and are usually underground. They can be made of concrete, fiberglass and some plastics. They are typically two chambers, the first one is to allow for large solids to settle and there is a baffle preventing floating scum and grease from entering the second chamber. The two chambers can be in the same tank or in multiple tanks.
The tank allows for some breakdown of the solids through anaerobic breakdown of the organic components. At this point the sewage treatment is a living process and it needs to be treated as such. Killing these bacteria will kill your treatment process, and increase the amount of pollution you release into the drainage system and the environment.
After the septic tank, water is discharged into the drainfield for further treatment by bacteria in the soil and filtering from the soil itself. The water is pushed along into the drainfield every time more sewage enters the tank. It can be pushed by gravity or by a pump depending on the design. If the drainfield receives too much water (rain and melt water included), it will flood, causing sewage to pool on the ground surface or backup into the house plumbing fixtures. Overloading also prevents proper treatment of all the wastewater, so not only will there be a lot more water, it will be of a much lower quality.
Many jurisdiction require a reserve drainfield. It is an area suitable for a new drainage system if your current system fails. Treat this area the same as your existing system.
Many areas have inadequate soils for groundwater dispersal. An alternative system will be needed in this case. Other reasons you may need an alternative system is if there are too many septic systems in one area or the system is too close to the water table or to surface waters. Alternative septic systems use more technology to improve treatment processes. They will most likely need special care and maintenance. Some alternatives use sand, peat, or plastic media in the place of natural soil to improve treatment. Other options are to use artificial wetlands/lagoons, aerators and disinfection devices but these will be covered in another article.
Some Notes on Drain-fields, DO NOT drive on or park vehicles on top of your drain-field. Anything that compacts the soil will prevent the dispersal of waterwater into the soil. ONLY plant grass on your drain field. DO NOT plant trees with aggressive roots anywhere near the drain field, the more aggressive the plant the farther away it should be. DIVERT rain water away from the drain field, to prevent flooding and sewage backups into the house.
Annual inspections are essential. Spotting a problem early is a lot cheaper to repair than waiting until it is a catastrophic failure of the system. This can be on the order of hundreds of times cheaper. Things that should be checked when inspecting your system are:
- Check the Sludge level. It should be lower than six inches from your outlet.
- Check Scum Blanket depth. It should be higher than 12 inches from the outlet.
- Check operation of any valves, pumps, floats and back-flow preventers. A lot of systems are built to be gravity powered, this is ideal because they are simpler (no pumps) and cheaper (no electricity).
- Check for leaks into and out of your tank.
- Check for lines of very green or burnt grass in the drainage field.
The most common maintenance on a septic tank is periodically they will need to be pumped out. The more solids that get added into the tank the faster the sludge will build up. Garbage disposals and people using the toilet as a garbage can (condoms and tampons are the leading culprits) lead to a lot of sludge build up. Avoid putting anything that can’t or wont decompose easily into your septic tank, it will just need to be pumped out later, and if there is a pump in your tank it will get clogged with sludge and YOU will have to clean it out. The scum blanket builds up fastest when people pour grease down the drain. Grease will eventually block your entire system if it is not kept in check. Do not pour grease down the drain. It is not good for the septic system or for a municipal sewer system…just don’t do it.
There are additives that claim to prevent the need for pumping, treat these claims cautiously. They may work as advertised, or they may not. I have never needed to use an additive in my septic tanks. If you keep the solid loadings low, the pumpings will be few and far between.
Wherever possible avoid putting non organics down the drain. In my article on liquid waste management I talked about the dangers of toxic liquids disrupting the biological treatment processes. If the biological treatment gets disrupted, the treatment drops to zero. This could be from cleaners, paints (even latex), disinfectants, oils and the list goes on. Remember to educate your guests as to the rules for septic tanks, many people are not aware they need to treat them differently.
That sums up your basic septic system maintenance. Remember to keep as many solids and greases out of your septic system along with anything disruptive to the biological treatment process. Inspect for leaks in the system and pump it out when necessary and your system will have a very long life.