Wastewater from toilets, bathtubs, and sinks flows through drain pipes into the septic tank. Heavy solids settle at the bottom to partially decompose and become sludge. Lighter grease and soaps float to the top and become scum. Effluent water exits from the tank to a soil absorption field. Click Here to learn more.
The soil in the absorption area naturally purifies the wastewater before it enters groundwater. A septic tank must be pumped regularly to keep it working properly.
For many people, drainage systems are invisible. They make wastewater disappear whenever we flush toilets or wash our hands, but few think about the mechanisms that make this happen. While sewer systems are more common because they’re funded and maintained by local governments, septic systems are growing in popularity as an affordable and environmentally sound alternative that gives homeowners full control over their drainage system.
A septic tank is a temporary holding tank for household waste where a small amount of treatment occurs. It consists of a precast concrete box about 5 feet tall and 9 feet long located underground. Wastewater flows into the septic tank from bathroom, kitchen, and laundry drains. The liquid waste that goes into the septic tank is called effluent, and it’s partially treated by bacteria in the tank.
A partition wall and an inlet and outlet baffle divide the septic tank into compartments. The inlet baffle helps keep sludge and solids from leaving the tank, while the outlet baffle draws liquid waste out of the tank for discharge to the leach or drain field. This ensures that solids don’t clog the absorption fields, which can lead to sewage flooding into homes or backyard ponds.
Once the effluent enters the drain field, it flows into the soil where bacteria further treat the wastewater. The bacterial action breaks down and digests contaminants before they’re washed into groundwater, where the bacteria continue to purify water.
If you’re a homeowner with a septic system, be sure to only flush items that are safe for your tank, like toilet paper and human waste. Other items, like paints and chemicals, may contaminate the environment or clog your pipes. These clogs aren’t just bad for the environment; they can also cause leaky drainpipes and sewage backups in toilets and sinks.
Household products that should not be poured down drains, including feminine hygiene products, cleaning and dishwashing products, baby wipes, dental floss, and pet litter can quickly clog a septic tank. Likewise, bleach should not be flushed, as it kills the microorganisms in a septic tank that break down sludge.
Drainage
A septic system is an efficient way to treat wastewater in homes without access to a municipal sewer network. The tanks and drain fields purify the water as it passes through, preventing contamination of soil and freshwater sources. The system’s design must follow strict regulations to ensure safe operation and protect the environment. A licensed septic tank design professional can assist with planning and building a system to meet the home’s specific needs.
A typical septic tank holds waste from toilets, sinks, tubs and washing machines. It has a large central opening and lid to allow the wastewater to enter and exit. A partition wall separates compartments within the tank. Heavy solids sink to the bottom of the tank where bacteria break them down to form sludge. The lighter solids, fats and grease float to the top where bacteria partially decompose them into effluent. An exit baffle prevents solids from flowing out with the liquid waste.
The septic tank also has a distribution box that evenly distributes the wastewater to pipes in the absorption field, called a drain field or leach field. The distribution box keeps the entire absorption field from flooding with too much wastewater at one time and clogging up the drain lines.
As the wastewater leaves the septic tank, it flows through a series of trenches that are dug in the soil and gravel to treat the wastewater further. The drainage field must be located away from houses and other buildings to prevent the sewage from seeping into or polluting surrounding land. A properly working septic tank and drain field can add value to a property and improve the quality of life for people who live in the home.
The septic tank should be sized for the number of people living in the house and their level of water use. Overfilling the septic tank can cause wastewater to overflow into the drain field, contaminating the soil and groundwater. Keeping the tank full of waste can also lead to backups in toilets and bathtubs. The septic tank must be pumped regularly by a professional to avoid overflowing.
Maintenance
As the septic tank fills with waste, heavy solids sink to the bottom and scum rises to the top. Bacteria break down the solids in the tank. The liquid wastewater (effluent) drains into the drain field through pipes, where it is absorbed by soil layers. As it flows through the soil, the bacteria further purify the water.
A properly designed septic system can handle the waste from three to eight years before needing service. The tank should be inspected every year, starting with the third year after it is in use, to determine how much sludge has accumulated. If 35% or more of the tank is taken up by sludge, it must be pumped out.
Having a septic system can save money on utility bills because it eliminates the need for a public sewer system. It can also protect groundwater from contamination by preventing sewage from leaching into the ground. However, it’s important to have the septic system regularly inspected and maintained to prevent leaks and other problems that can cause water pollution and contaminate well-water supplies.
Septic tanks have been used in the United States since the early 1860s. They can be expensive to replace or repair, so they should be inspected and maintained on a regular basis. A septic tank that is not adequately maintained can contaminate the environment and create health hazards for humans and animals.
Maintaining a septic system includes keeping the area surrounding it clear of plants and structures that could be damaged by leaking or broken tank components. It is also necessary to periodically remove sludge from the tank, which can be expensive.
Another maintenance task is ensuring that the septic tank is buried underground at a proper depth to ensure it does not fail due to being overloaded with sewage or being subjected to excessive ground water. It’s also important to have a proper lid and riser cover that can be easily removed for pumping, inspection and maintenance.
In addition, homeowners should have a map or clearly mark the location of the septic tank and other system components to avoid damaging them when doing yard work or home repairs. Also, they should not park vehicles or drive equipment over the system or build structures that would cover the tank or absorption field.
Safety
A septic tank should always be properly sealed with a lid that is secure. This is very important because many people, especially kids, fall into the septic tank through a broken lid or an opening that is not sealed correctly. These accidents are usually very serious because they can result in suffocation, drowning or serious injuries.
It is also essential to know where your septic tank is located and avoid unnecessary movement around the area. This is because a septic tank and the septic system’s connected pipes for effluent release can be damaged by excessive weight. The resulting damage may cause the indiscriminate release of wastewater throughout the property, which can contain harmful microorganisms.
Another danger of a septic tank is its emission of hydrogen sulfide gas. This gas is produced as the waste breaks down in the septic tank, and prolonged exposure can have serious health consequences. A low level of exposure can cause irritated eyes, a cough or sore throat, shortness of breath and fluid accumulation in the lungs. If the levels of hydrogen sulfide are high enough, it can lead to dizziness, confusion, loss of consciousness and death.
Keeping the septic tank and absorption field well-maintained is essential to prevent contamination of the surrounding soil and groundwater. To do this, you should keep septic tanks, inlets and outlet tees clear of obstructions. Moreover, you should never plant grass or any other plants with deep roots over the tank, inlet or drain field. The roots can grow into the pipes and clog them. You should also prevent the flow of water and sewage to the septic tank from nearby structures such as pools, ponds or storage buildings.
Finally, you should schedule regular inspections of your septic tank and the absorption field by qualified professionals. This will allow you to catch any problems before they become more expensive and dangerous. It will also ensure that the septic tank is pumping and absorbing as effectively as possible.