A septic tank is a large, watertight container where solid waste is separated from wastewater. Heavy solids settle to the bottom and form a sludge, while oils and fats float to the top, where aerobic bacteria decompose them.
The clarified wastewater, known as effluent, exits the septic tank through a distribution box and perforated pipes into a soil absorption system called a drain or leach field. This is designed to treat the wastewater as it seeps into the ground. Click the https://www.septictankarmadale.com.au/ to learn more.
Wastewater treatment involves a complex series of steps that remove pathogenic bacteria, viruses, and excess nutrients. This prevents these pollutants from polluting nearby groundwater wells and bodies of water.
The first step is a preliminary screening process that removes large particles such as sticks, garbage and grit from wastewater. This is done by screening and aerating the wastewater before it enters a septic tank. The aerated wastewater is then delivered to a septic tank that is designed with compartments and a T-shaped outlet to separate solids from liquid waste. The septic tank is usually made of concrete, fiberglass or polyethylene and is buried under the ground.
In a conventional system the liquid wastewater (known as effluent) is discharged from the septic tank through a network of perforated pipes that are buried in a gravel-filled trench called the drain field. The effluent flows through the soil where it undergoes further treatment by filtration through gravel and soil, chemical reactions with organic matter and decomposition by microorganisms in the soil.
The septic tank also contains an anaerobic chamber that is filled with a black, jelly-like substance known as biomat. The biomat is composed of anaerobic microorganisms that attach to the bottom and side walls of the septic tank and digest the sludge in the tank.
As the septic tank fills up with wastewater, the biomat slowly seeps to the bottom of the tank and breaks down the solids into a slurry. The sludge is removed from the tank periodically and pumped away for disposal at a landfill.
A septic tank that does not get pumped often enough will lose its effectiveness at separating solids from the wastewater. This can cause a sludge layer to build up in the tank, clogging the outlet pipe and preventing the wastewater from exiting the tank. It can also result in the septic tank filling up with untreated sewage.
Homeowners can help their septic systems function more effectively by not flushing non-biodegradable waste items down the toilet such as cigarette butts, cotton swabs, feminine hygiene products and condoms. They should also spread their loads of laundry over the week to avoid overloading a septic tank. Finally, homeowners should not build structures, such as decks and patios, over the septic tank or drainage field. This can damage the tank and drain field and interfere with the system’s function.
Septic Tanks
A septic tank is a buried,watertightt container made of concrete, fiberglass, or polyethylene. Its job is to hold wastewater long enough for solids to settle down to the bottom (forming sludge) and oils and grease to float to the top (as scum).
Bacteria in your septic tank generate gases as they break down sewage contaminants. These gases must be released to prevent a build-up of pressure that could stop or reverse the flow of wastewater. Gases are released through a vent pipe located in the tank lid. The vent typically has a mushroom shape and can be fitted with a charcoal filter to reduce odors.
The liquid wastewater called effluent exits the septic tank through an outlet pipe and is discharged into an absorption area, which may consist of a series of perforated pipes buried in stone-lined trenches, mounds, seepage pits, or other special units designed to slowly release the liquid into soils. In decentralized systems, a septic tank acts as the first point of treatment before the wastewater enters the absorption field.
A septic tank must be installed on a solid and level surface. It must be free of any cracks or other defects that might allow groundwater to leak into the tank. It should also be set back from the property line to prevent animals or vehicles from walking into the tank. The septic tank must be installed with a riser at grade so it can be accessed for pumping, maintenance, and inspection. This allows the tank to be pumped without digging up the entire yard and avoids the cost of installing a new drainfield. A septic tank with a pump should have alarm switches and an effluent filter at the outlet to prevent solids from leaving the tank and clogging the drainfield. The tank should also have a distribution box to evenly distribute the liquid wastewater to the pipes in the absorption field. This will help extend the life of the drainage field by preventing premature clogging and bioclogging.
Drain Fields
A septic system relies on the drain field, also known as a leach field or absorption field, to accept, treat and disperse wastewater. The drain field is an underground network of perforated pipes that are surrounded by a layer of porous material such as gravel. As the wastewater trickles through the perforated pipes, bacteria in the soil break down contaminants and the clean water naturally percolates into groundwater.
The septic tank contains three layers of waste: solid waste settles to the bottom forming sludge, and oil and grease floats on top forming a layer of scum. Compartments and a T-shaped outlet prevent the two layers from leaving the tank. Bacteria inside the tank process sludge and scum, removing a significant amount of the pollutants from the liquid wastewater (effluent). The liquid waste then exits the tank into the drain field.
Typically, the leach field sits lower than the septic tank to utilize gravity to help wastewater flow out of the system and into the drain field. A distribution box may be used to evenly distribute the effluent to multiple areas of the drain field.
A septic system’s drain field requires well-drained soil. To determine if the soil can properly absorb the septic tank’s effluent, a perc test is commonly performed. The test evaluates the soil’s ability to retain and aerate water, as well as how much space it has for wastewater to pass through.
Although septic tanks are designed to handle the average home’s waste, systems can become overloaded by sending too much wastewater at once into the septic tank or drain field. This can be caused by multiple loads of laundry being done on the same day, using a dishwasher and washing machine at the same time or flushing items that shouldn’t be in your septic system (such as paper towels, feminine hygiene products, tampons, pet feces, hazardous chemicals).
The best way to maintain your septic tank and drain fields is through prevention. Avoid driving or parking over the septic drain field as excessive weight could crush the pipes below. It is also important to avoid putting any solids into your septic system, especially into the toilets. Instead, you should buy septic safe toilet paper and products, use lowflush toilets, and avoid pouring fats, oils or grease down your drains. These will clog the system and disrupt the helpful bacteria that work to break down contaminants.
Pumps
There are many things that can go wrong with a septic tank and septic system. Following best practices like keeping a regular emptying schedule, not flushing solid items, and avoiding using garbage disposals are important to help your septic system function properly. However, a lot of issues can arise beyond the control of homeowners and they require professional attention to repair.
The septic tank is a large, sealed precast concrete box that is buried underground near the home. It is designed to hold household waste in a temporary storage area where a small degree of treatment takes place. The septic tank is aerated to promote the growth of aerobic bacteria that digest suspended solids and other wastewater contaminants. Once the tank fills, the wastewater is pumped into the drain field, where it is further treated by soil layers.
During the septic tank process, the liquid waste (effluent) is separated into three distinct zones. The top layer contains oils and grease that float on the surface of the liquid. This is commonly referred to as the scum layer. The middle layer is the wastewater itself, and the bottom layer is the sludge. The sludge layer is the most dense portion of the waste and is comprised of materials that are harder to break down, such as spent cell walls, mineral precipitants, detergents powders, some soil from bodies and clothes, partially digested food products and other solid waste.
An inlet baffle is located at an elevation below the scum layer and above the sludge layer. This is to enhance the deposition of the dense solids and reduce the velocity at which the fluid enters the pumping station. The exit baffle prevents the separated solids from leaving the tank. This is important because these solids can easily clog the septic tank and absorption field.
The septic system must be pumped regularly to remove the accumulated solids from the septic tank and ensure that the clear wastewater is dispersed through the soil absorption field. This prevents the clogging of the absorption field and keeps the wastewater flowing freely without causing a backup in the home plumbing system. In some cases, the septic tank may need to be emptied more frequently if the wastewater load exceeds the capacity of the tank.