Bacteria in your Septic Tank Armadale generate gases as they break down wastewater contaminants. These gases must be released to prevent a build-up of pressure that could stop or reverse the flow of sewage.

Heavier solid matter sinks to the bottom of your septic tank and forms sludge; lighter material floats to the top and forms scum. Anaerobic organisms break down organic waste and the resulting effluent returns to soil and groundwater.
Domestic sewage from toilets and wastewater from showers, tubs, sinks, dishwashers, and washing machines runs into the drain pipe that leads to the septic tank. Heavier solid matter (like feces and toilet paper) sinks to the bottom of the tank to form sludge, while lighter waste (like fats, oils, and greases) floats to the top to create scum. The liquid in between, known as effluent, is partially digested by anaerobic bacteria. The septic tank must be large enough to hold the total volume of sewage that flows into it.
The inlet pipe is fitted with a baffle to slow the flow of water entering the septic tank, preventing hydraulic overload. The inlet baffle also helps prevent odorous gases from escaping into the home or building. The baffle and tees are made of acid-resistant concrete, cast iron, or plastic. Six-inch diameter inspection pipes extend above the baffles and tees for checking on sludge levels and clogs.
If septic tank inlet and outlet lines become blocked by sludge, the system is overloaded. The septic tank must be pumped. Overloaded septic tanks can also damage the absorption field, resulting in sewage seepage into the ground surface or contaminating groundwater.
A septic tank should be inspected at least once a year to ensure that the sludge and scum layers are not rising above the effluent level. If the sludge layer is more than 1/3 of the tank’s capacity, or the scum layer is above the inlet level, the septic tank is overflowing and needs to be pumped.
Septic tank experts disagree on whether baffles are necessary. Critics point out that the natural settling and rising processes within the septic tank are sufficient to separate solids, sludge, and effluent. They further argue that adding baffles can actually interfere with the natural process and cause clogs and abrasions in the inlet pipe and tees. The tees and baffles should be secured to the tank with an appropriate seal, typically silicone caulk.
Outlet
Wastewater from your toilet (called blackwater) and the wastewater from showers, bathtubs, sinks, washing machines and dishwashers (called greywater) drain into a main drainage pipe that leads to the septic tank. The septic tank is designed to hold these domestic sewage wastes for at least a day to allow bacteria inside the septic tank to decompose some of the organic materials in the sewage. Heavy solids, such as dirt and digested waste, sink to the bottom of the septic tank to form sludge. Lighter matter, such as fats, oils and greases float to the top of the septic tank to form a layer of scum. The septic tank’s lid is sealed with a rubber gasket to prevent the ingress of air.
Bacteria in the septic tank use anaerobic decomposition or digestion to break down the organic waste material in the wastewater. In this process, the organic matter is decomposed without oxygen in the septic tank to produce carbon dioxide and methane as byproducts. This process also kills any disease organisms in the sewage. The liquid effluent that results from the bacterial digestion is then discharged into your absorption field.
Your septic tank has an inlet baffle and an outlet baffle to prevent the mixing of sludge with the pristine effluent that leaves the septic tank. The inlet baffle directs the wastewater into a longer path across your septic tank to give the solids more time to separate out into sludge and scum. It also prevents solids from entering the drain field or back into your home.
The outlet baffle serves a similar function to the inlet baffle by slowing down the rate at which the wastewater exits the septic tank. This gives the bacteria in your septic tank more time to break down the remaining solids and sludge.
The watertight outlet piping of your septic tank is connected to the distribution box and perforated pipes in your absorption field. These pipes should be at a slight slope, with a 1/4-inch drop in 10 feet of distance, to ensure that wastewater seeps evenly into the ground and into soil that is clean enough to return to surface and groundwater sources.
Venting
Located underground, your septic tank is the first step of your home’s wastewater treatment system. Domestic sewage from your toilets (called blackwater) and wastewater from your sinks, bathtubs, showers, washing machines, dishwashers and other appliances that you use in the home (called greywater) runs through the main drainage pipe that leads to your septic tank. Heavier solid materials settle down to the bottom of your septic tank forming sludge, while lighter matter like fats, oils and grease floats to the top and forms scum. Over time, bacteria break down the organic wastewater pollutants in your septic tank and the resulting liquid wastewater (effluent) exits into the absorption field.
Your septic tank needs ventilation so that air can move freely through the system, helping to decompose waste and avoiding unpleasant odors. Without adequate ventilation, the microbes in your septic system can become anaerobic (devoid of oxygen) and fail to break down waste efficiently. This can lead to gas buildup and odors, as well as blocked drains.
A septic tank vent pipe is found near the leach field in your yard. It is usually shaped like a periscope or candy cane, and it is easily identified by its white cap. A septic vent pipe is essential to your septic tank because it allows excess pressure in the tank and absorption field to escape. This prevents damage and prevents sewage from entering your home’s plumbing.
The septic tank vent also helps keep the sludge level in your septic tank from getting too high. This ensures that your septic system is efficient, which means less waste is left behind in your drainage field, and fewer nutrients enter the groundwater supply and ecosystem.
Unless you’ve been living on your property for a long time, it can be difficult to know where the septic tank is located. However, it’s important to know its location so that you can avoid digging into it, and to keep an eye out for the lid, which should be buried no deeper than four feet below ground. There are ways to locate your septic tank, including by using a septic system map that’s often provided by the county or your septic service provider, and by consulting information from previous owners.
Maintenance
If your home is not connected to a municipal sewer system (or septic tank), your wastewater must be treated on-site. The main parts of a septic system include a line that transports your wastewater to the tank, the septic tank itself, the drainage field, and more. By understanding how each part of a septic system works, you can better protect your family and the surrounding environment.
Domestic sewage from toilets and wastewater from showers, sinks, washing machines, and dishwashers run through a main drain line that slopes downward toward your septic tank. The wastewater is carried by gravity into the septic tank, where it is held until solids and liquid waste separate. Heavier solid matter – like human waste and cooking scraps – sinks to the bottom of your septic tank, where it forms sludge. Lighter waste materials – such as fats, oils, and greases – float to the top of your septic tank, where it becomes scum. The sludge and scum are separated from the liquid wastewater, which exits your septic tank as partially purified effluent.
Your septic system has a drain field that carries the liquid wastewater into soil and grass for absorption and filtration. This process provides another level of treatment and contaminant removal, making the water safe for groundwater and nearby drinking water wells. Regular septic tank pumping and care for the absorption field help your septic system operate efficiently.
A septic tank is an underground, watertight container made of concrete, polyethylene, or fibreglass that receives and holds household wastewater until it can be disposed of in the drain field. A septic tank is the first step in your septic system and is important for homes in rural areas without access to municipal sewer lines.
The best way to protect your septic system is to prevent it from becoming overloaded with debris. Avoid flushing non-biodegradable waste, and schedule annual tank checks to keep your septic system functioning properly. Keeping your septic system healthy also helps reduce the risk of costly repairs and ensures that sewage is not polluting nearby waterways or drinking water wells. The old adage, “An ounce of prevention is worth a pound of cure,” perfectly encapsulates the importance of proper septic system maintenance.