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What is a Septic Tank?

A septic tank is a buried, watertight container that holds wastewater. Solids settle to the bottom of the tank forming sludge, and fats, oils, and grease float to the top, forming scum.

Bacteria in the septic system break down this organic matter anaerobically. The septic tank then discharges wastewater into a distribution box and perforated pipes that drain into absorption fields or seepage pits in the soil. For more information, you can visit Septic Tank Armadale to proceed.

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The wastewater from your toilets, baths, and sinks (called blackwater) and kitchen appliances like dishwashers, washers, and refrigerators (greywater) flow into a drainage pipe that leads to the septic tank. The tank holds the waste long enough for solids to settle and float. Heavy solids sink to the bottom and form a layer of sludge, while lighter solids, such as fats and oils, float to the top and create a layer of scum. Bacteria in the septic tank digest these wastes and liquefy them. The liquid that remains is called effluent.

The liquid that exits the septic tank should be free of floating debris and contain no more than two percent solids. It should also have a screen or filter at the outlet to prevent the sludge from entering the absorption field or leach field and clogging pipes.

As the septic tank treats the wastewater, it generates gases that must be vented to the outside air. The gases include hydrogen sulfide, which has an odor similar to rotten eggs. These gases are released through a PVC “T”-shaped fitting, usually near the top of the septic tank or through a septic system pump station with an odor control vent.

After the septic tank treats the wastewater, the liquid is discharged to a distribution box or, in non-traditional systems, directly into a perforated piping network buried in trenches or mounds, called an absorption field or drain field. This piping network is designed to release the partially treated wastewater into the soil slowly. The bacteria in the soil absorb and eliminate impurities from the wastewater through percolation, evaporation, and uptake by plants.

The septic tank must be sized correctly to avoid overflowing and contaminating the absorption or drain fields. A septic tank manufacturer can advise homeowners on the size of the septic tank needed for their home. Some septic tanks are made of concrete, fiberglass, or polyethylene, which resist cracking underground and are less likely to leak. The septic tank should have a watertight lid, a strong seal, and a sturdy access ladder or ramp for easy maintenance.

A septic system is required when you live in an area not connected to a public sewer or sewage treatment plant. This system collects household waste in a tank, usually made from fiberglass, concrete, or plastic, and is set underground. The wastewater leaves the tank into a drain or leach field, where the sewage is further treated by absorbing it in the soil below. The system may also have a vent allowing gases to escape the tank.

When solid waste enters your septic tank, bacteria in the tank start to break it down. Some of the concrete waste sinks to the bottom of the tank, forming a sludge layer. Some fats and oils float to the top of the tank, creating a layer of semi-solid scum. Bacteria in the septic tank produce gasses that must be vented out of your home to avoid a build-up of pressure that could damage the septic tank or prevent liquid waste from leaving. These gases are typically odorless, but some may be unpleasant.

Once your septic tank has been installed, it must be linked to the absorption field or drain field by a pipe. The absorption field is a network of trenches filled with washed gravel, stone, or a graveled product. A distribution box is often placed on the ground’s surface to distribute the wastewater evenly among the several sections of a drain field.

While the septic tank costs considerably less than an aerobic septic system, installation can be quite costly, including excavation and drainage field preparation. The cost can vary based on the condition of nearby soil and how deep the tank will be dug.

Once the tank is in place, avoiding driving or parking heavy vehicles or equipment over the septic tank and absorption field is important. This can cause serious damage to the tank and the system. It is also important to avoid covering the drain field with grass, playgrounds, or other impermeable surfaces. Keeping the tank and absorption field clean will help extend their lifespan.

Septic systems are not without risks, but a well-maintained tank can last 40 years or more. Proper care and maintenance ensure the septic system operates correctly, preventing bacteria and contaminants from entering the drain field, where they can cause costly problems.

The septic tank acts as a settling basin, where heavy solid waste sinks to the bottom of the tank and is broken down by bacterial action. Lighter solids, such as oils and fats, rise to the top and form a layer of scum. The wastewater leaves the septic tank through the outlet tee pipe, which opens into the drain field and is often buried underground.

A septic tank should be located in a location that is just a short distance from a house or driveway. If the septic tank is too close, the weight of cars and trucks passing over the septic system can cause the septic tank to crack or leak. The size of the septic tank should be determined by the number of people living in the home and how much liquid waste the septic system is expected to process daily.

Maintaining the proper flow of water through the septic system is important, as overflowing can damage the septic tank and surrounding soil. The septic tank should also be vented properly so that gases produced by bacterial decomposition can escape. The gases can include hydrogen sulfide, which has a strong odor similar to rotten eggs.

During anaerobic digestion, the septic tank fills with indigestible solids that must be removed periodically. Unless this sludge is pumped out, the wastewater discharge from the septic tank will enter the drain field and may clog the leach field piping or decrease the soil porosity of the leach field itself, leading to expensive repairs.

Septic tank sludge should be pumped out at least once every three years to prevent clogging. A septic tank expert can help determine when the time is right for your home to have its septic tank emptied. The tank should also be inspected to ensure it is large enough for your household and that the leach field is adequately sized to treat your wastewater effectively.

A septic system takes waste from the home, treats it, and returns it to the soil. The septic tank or tanks holding the processed waste play a critical role in the process, but like all mechanical systems, they can break down and require replacement.

Generally speaking, the lifespan of a septic tank is 20 to 40 years. The most obvious sign that it’s time to replace the septic tank is when the expected lifespan has passed and problems occur. Frequent sewage backups, slow drains, and toilet clogs are all signs of a failing tank or septic system.

A failing septic tank can also result in a build-up of solid waste inside the house. This can cause a wastewater spill into the home or bring standing water into connected plumbing in the bathroom and kitchen, which presents both a visual and olfactory problem for homeowners.

If the septic tank is properly sized, it may need more volume to separate liquid and solid wastes. An undersized tank can also lead to the overflow of septic system materials, which may clog drain fields or leak into the surrounding environment.

The size of a septic tank can be determined by examining the inlet and outlet. The inlet is a PVC “T”-shaped fitting that connects to piping on the exterior of the septic tank. The outlet is a longer vertical section of piping that extends several inches below the top of the scum layer.

Lastly, a failing septic tank can be caused by improper placement of the drainage field. Placing the tank too close to the home or covering it with a driveway, storage building, or other impervious surface can seriously affect its performance and increase the risk of failure.

When installing a new septic tank, it’s best to leave the work to professionals. A successful septic tank installation requires knowledge of sewer systems, specialized machinery, and extensive digging to properly place the septic tank in a location that supports its function. It’s also a good idea to obtain the proper building permits to ensure the tank is installed legally and by local regulations.