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How Does a Septic Tank Work

Interested to find out how a septic tank works? In this article we will explore the most important things to know about septic tanks, and show you the benefits of using a septic tank.

In every home, all household plumbing has to go somewhere. All the waste we produce must be filtered before going back into the water cycle. Urban areas often use a city sewer system. The waste from every home and business in an area goes into one collective sewer main. This wastewater then travels to a treatment plant for filtering.

Rural areas don’t have this convenience due to the larger distance between homes. A sewer system would be too expensive to install, so private septic systems are installed to filter the wastewater. These private septic systems consist of a septic tank and a drainage field also known as a leach field.

How A Conventional Septic System Works

A conventional septic system consists of two main components—the septic tank and the leach field. The septic system is completely passive and can filter waste naturally. Gravity helps the waste separate and travel to its targeted destination while bacteria filters the water. The septic system takes all the sewage that leaves your home and makes it safe to enter the environment again. Not only does this sewage need somewhere to go to hide its horrible odor, the harmful bacteria and chemicals have to be filtered out before it gets to other sources of water. These pollutants can affect the environment and wildlife is the first to suffer from the effects of polluted water in lakes or streams.

Conventional septic systems don’t require any mechanical parts to work. The engineered septic system can be upgraded, however, to work more efficiently. Pumps can be added to improve the filtering process. Some landscapes are also not ideal for a conventional system. This might require you to include more steps in the process than you would get with a basic septic system design.

All the waste from the bathroom, kitchen drains, and washing machines leave the home in one drainage pipe. This pipe leads directly into the septic tank.

How Does a Septic Tank Work - NexGen Septics

The Septic Tank

A septic tank is a large concrete or steel tank that can hold 1,000 gallons of water. Wastewater enters the tank through one end and leaves on the other. There are three layers in a septic tank system. The bottom layer is called the sludge layer where solid wastes collects. Bacteria in the tank breaks down the solid waste material that sinks to the bottom. The top is called the scum layer, and this consists of lightweight waste such as grease or fat. The middle layer is the wastewater also called the effluent. The wastewater in this layer still needs further filtering before it’s ready to enter the groundwater. When new wastewater enters the septic tank, the overflow of effluent enters the drainage pipe to travel to the drainage field.

How Does a Septic Tank Work - NexGen Septics

The Leach Field

The drainage field, or leach field, is the final step in the septic system. This consists of perforated pipes in trenches filled with gravel or sand. Each pipe is four inches in diameter. They are inserted into trenches that are four to six feet deep and two feet wide. Gravel or sand surrounds the pipe and is topped off with soil. The water that is distributed into the pipes slowly enters the ground through the drain field. Here more bacteria filter the water before it enters the groundwater safety free of pollutants. Water should be absorbed by the soil at the right rate.

It’s easy to locate the drainage field on your property. Just look for the greenest area. The grass around the drainage field takes advantage of the water released from the pipes. It’s important to know where this area is so that you can watch out for any signs of septic system failure.

Septic Tank Maintenance

While a septic system can filter sewage unattended, there are still things the homeowner needs to do to keep it running smoothly. Problems with the septic system can lead to sewage backing up into the house or overflowing into your lawn. Clogs, cracks or backups are problems that will only get worse the longer you ignore them. Properly maintaining septic systems can allow them to last for many years without needing to have any major installation done. There are many ways to keep your septic system functioning.

Things To Avoid To Keep Your Septic Tank Functioning

An important thing to remember is that all the waste that leaves your home through the plumbing will end up in your septic tank. This means anything flushed down the toilet or garbage disposal ends up there. Don’t flush anything into the septic system that shouldn’t be there. This can include diapers, feminine products, kitty litter or chemicals. Also, be careful of products that claim they are “disposable”. Not all products are safe to enter the septic system. Even some toilet paper products aren’t designed to break down in the septic tank which can cause clogs or build up.

The drainage field needs to be properly maintained as well. Driving over the leach field can cause damage to the pipes. The soil and gravel surrounding the pipes can compress under the weight of a vehicle.

Avoid roots damaging the septic system by keeping trees with long roots far away from the area. Roots can get into the drain field, pipes and septic tank. This can cause clogs or even cracks that will disrupt the system.

Signs Of Septic System Failure

There are many signs that your septic system is having problems. One could be slow draining in sinks or bathtubs. Toilets can also have trouble flushing. These are both signs that the septic tank is not dispelling the wastewater in the tank quickly enough to take in the new wastewater. You might even notice a foul odor coming from drains in your home which can lead to sewage backing up into the house.

If you notice your lawn getting lusher and greener around the leach field, this might not actually be a good thing! This can show signs of problems with the outlet pipes. There could be a blockage or even a break that is spilling excess water into the soil.

Noticing any of these problems is the first sign that you need to call your local septic tank expert to repair any damage to your system.

Finding A Septic Tank Expert

How Does a Septic Tank Work - NexGen Septics

Septic systems can’t last forever. Eventually, maintenance by a professional needs to be done to keep the septic tank working correctly. Call a contractor at any sign of problems with the septic system, but they also should be doing routine maintenance to your septic tank. Every three to five years, you need to have a contractor perform a septic tank pumping. The solid waste in your tank will build up over time and there won’t be enough room in the tank for anymore waste. Having your septic tank pumped routinely will be a way to ensure a long healthy life for your septic system.

Not only can you call a septic expert for problems with your septic system, you can also install a new system. This might sound like a daunting task, but upgrading your septic system is a great investment into your home. There are alternative septic tanks that will speed up the filtering process that will allow for a smaller septic tank.