A septic tank collects waste from your toilets, showers, sinks, and garbage disposal. The waste enters the septic tank, and bacterial activity breaks down most of it.
Heavy solids sink to the bottom, forming a layer called sludge. Oils and grease float to the top and form a layer of scum. Liquid wastewater exits the septic tank through perforated pipes and enters an absorption or drain field. Contact Septic Tank Armadale now!
When people buy a home in a rural area, one of the first things they think about is all that extra space. However, another thing they might need to think about is all the work that comes with a septic system. That’s because septic systems don’t just provide space; they also treat wastewater.
All the wastewater from your home runs through a single drainage pipe to the underground septic tank. There it’s held long enough so that the solids sink to the bottom of the tank and oil and grease floats to the top. The clear liquid left is called wastewater or effluent. The sludge layer on the bottom is what needs to be pumped out regularly as part of your septic system maintenance.
Bacteria in the septic tank create gases as they break down these wastewater contaminants. These gases must be released to prevent a build-up of pressure that could stop or reverse the flow of wastewater. A vent on the septic tank lid releases these gases. It often has a mushroom shape and can be fitted with a charcoal filter to reduce odors.
Once the wastewater has left the septic tank, it seeps into a drain field or leach field. This is a series of perforated pipes in the soil that filters wastewater as it seeps down through rocks, dirt and sand to groundwater.
When homeowners don’t maintain their septic systems, they can cause problems like leaks in the drainage pipes or even sewage back up into their homes. They can also damage the drain field, which requires a lot of money to replace. The most common maintenance tasks include cleaning the inlet and outlet baffles, replacing the septic tank liners and replacing the drain field or leach field.
The best way to prevent septic system maintenance problems is to watch what goes down the drain. Non-biodegradable items like cigarette butts, cotton swabs and sanitary products can cause clogs and prevent wastewater from exiting the tank. It’s also a good idea to only flush toilet paper and other products that are septic safe.
Sludge
A septic tank treats and disperses wastewater from household plumbing. Its inlet and outlet pipes connect to a drain field that disperses the pre-processed wastewater back into the soil. Depending on the size of the septic system and its use, a septic tank can store waste for up to three to eight years before it requires pumping. The sludge layer contains the heavier masses of organic, natural waste that remain undigested. This inorganic sludge can be very thick and will clog the drainage field if allowed to build-up.
A healthy septic tank has no more than 30% of its volume taken up by the sludge layer. The tank should be checked on a regular basis to ensure it doesn’t reach this point. Homeowners can use do-it-yourself tools to measure the sludge level or simply ask their septic service provider when they should plan for the next tank pump-out.
When the bacteria in a septic tank work through the sludge layer, they release methane and noxious gases. This is because sludge lacks oxygen and the bacteria can only digest so much of it before they run out of gas-producing power. The sludge layer also prevents water from exiting the tank through the inlet pipe if it is too thick.
Keeping the sludge layer in the septic tank at a minimum will help reduce the amount of time between tank pumping. However, it is important to understand that the septic system will eventually need to be pumped out regardless of how low the sludge levels are.
It is also essential to avoid flushing non-biodegradable substances down the toilet such as cigarette butts, cotton buds/swabs and menstrual hygiene products. These items can cause septic tanks to fill rapidly and clog the septic drainage system, so they should be taken out of the home and disposed of properly.
There are a number of products on the market that claim to extend periods between septic tank pumping, but most of them contain chemicals that throw the primordial ecosystem of a septic tank out of balance and can disrupt the bacteria’s ability to digest waste. Instead, use a biologically based digestion treatment like Muck Munchers to keep the inorganic waste in your septic tank to a minimum and get it to drain and process more efficiently.
Scum
As the wastewater in a septic tank settles, the density differences between the different components of sewage allow layers to form. A scum layer forms on top, which consists of fats, oils and greases that float. A bulk liquid layer forms in the middle, and a thick sludge layer settles on the bottom of the tank. Each of these layers is distinct, and the septic system is designed to keep them separated from each other.
The scum layer in a septic tank can be as much as 40% of the total volume. It is very clear, greenish-grey or even brown in color, and it generally has a bubbly consistency. It is common for toilet paper and other small solids to float on top of this layer, too.
When the septic tank is functioning correctly, the scum layer is thick enough that it keeps most of the waste materials from entering the drain field, where they would be further treated by microorganisms in the soil. The septic tank also contains a large amount of water that occupies the space between the sludge and scum layers. The septic tank is often designed with an effluent baffle to ensure that the scum layer stays in the septic tank and doesn’t enter the drain field.
A septic tank should be pumped regularly to avoid the buildup of an excessive scum layer. This layer can block the outlet and clog the drain field, which is dangerous for the health and safety of the home’s inhabitants. The frequency of septic tank pumping depends on the size of the septic tank and how much waste it holds, but it should be pumped at least every two to three years with normal use.
If a septic tank doesn’t have a scum layer, it is an indication that it isn’t operating correctly. It may require a thorough inspection of the septic system to determine why it isn’t producing the necessary separation layers. This might involve looking at a tank’s internal dimensions, assessing if the microbial community is healthy, and examining whether chemical additions are impacting bacterial activity.
Effluent
Some companies make and sell biological additives that they claim restore the bacteria balance in a septic tank. However, these are unnecessary because the natural bacteria that reside in human feces already do this job very well.
A septic tank is an underground, water-tight container that holds wastewater for extended periods of time. It provides a quiescent body of water that allows solid waste to separate from the liquid through a process called both settling and flotation. Substances that are heavier than water (grit, unconsumed food particles, oils and grease) sink to the bottom of the tank forming sludge. The lighter substances (human waste, toilet paper) rise to the top and form a scum layer. The clarified liquid between the scum and sludge is known as effluent, also referred to as wastewater. The effluent then exits the tank through the outlet into an absorption area, commonly referred to as a drain field.
In order to maintain a high quality of effluent, septic tanks must be pumped regularly. This prevents the accumulation of solids that will clog the pipes and gravel in the drainfield. When solids contaminate the effluent, it becomes a health hazard to people and pets and can cause unpleasant odors and bacterial growth in the drainfield.
Flowing from the septic tank into the drainfield, the liquid wastewater passes through a series of perforated pipes and gravel beds where it is treated by soil. The soil absorbs and neutralizes disease-causing pathogens, nitrogen, and phosphorus.
Septic tanks are more effective than other septic system designs, such as seepage pits, mounds and cesspools. The septic tank is buried beneath the ground and connected to all plumbing connections in your home through an inlet and outlet tee.
Inlet and outlet tees extend below the scum layer to the surface, which causes hydraulic pressure to force wastewater up through them into your absorption field whenever you flush a toilet. The tees also ensure that the scum layer remains in the tank with the sludge layer so that solids do not pass into the absorption field. This helps to reduce the amount of maintenance required for the septic tank and absorption field, and it helps to protect the longevity of the septic system.