What Is a Septic Tank and How Does It Work?

Here at Need a Tanker, we offer our customers a wide range of services related to collecting and disposing of all kinds of liquid waste. One of the most common things that we’re asked to do is empty or service a septic tank. Most people will have heard of a septic tank, but not everyone will necessarily know what one is or how one works.

Emptying a household septic tank on a street. Unrecognizable Caucasian male manual worker cleaning sludge and mud from a sewage system.

So, as the first article on our new blog, the team at Need a Tanker is going to be answering these questions. Let’s start with the basics:

What Is a Septic Tank?

For most people, when it rains and the rain goes down their drainpipes, when they flush the loo or wash any kind of wastewater down the sink, they don’t have to think about what happens next. That’s because it all heads into the drains and on into the sewerage system, where it gets treated well away from where we live.

Many houses, however, for one reason or another – often because they’re remote from other properties – aren’t connected to the main sewer system. If that’s the case, they need something else to capture all that liquid waste, because if it just gets emptied into the environment, it could do untold damage to wildlife and plant life in the area.

This is where a septic tank comes in. Properties that aren’t connected to the main sewers will usually have an underground tank that captures all that liquid waste and separates it out to leave clean water that can be emptied out into the local environment, and solids that need to be collected and disposed of safely.

A septic tank is usually made of fibreglass or plastic. Some older properties may have a concrete cesspit, which does a very similar job but, unlike a septic tank, does not treat the wastewater in any way.

How does a septic tank work?

A septic tank will be buried underground, but will need to be easily accessible. It is usually made up of at least two compartments, with an inlet pipe at one end and an outlet pipe at the other.

Wastewater from the property in question is fed into the tank’s first compartment through the inlet pipe. There, any solids settle at the bottom of the tank, while scum, such as grease and oil, floats to the surface. The cleaner water left in the middle feeds into the second tank, where a similar process takes place.

By this time, the water that is left is clean enough to be emptied through the outlet pipe and into a soakaway or drainage field. There, bacteria can break down any remaining impurities so that it won’t cause any damage.

Meanwhile, bacteria in the tank eats away at the remaining sewage reducing it to almost nothing, and meaning that there should be plenty of room for the next wave. Nevertheless, what is left inside the septic tank still builds up over time, and therefore does need to be emptied every now and then. Just how often will depend on the size of the tank and how many people live at the property in question, but generally it will be once every three to five years.

To make sure your septic tank is working properly and not putting your local environment at risk of being poisoned – not to mention meaning you won’t be liable for substantial fines for allowing that to happen – you need to make sure you use a reliable and professional team of experts to keep an eye on it. Here at Need a Tanker, we provide extensive services for those with a septic tank, including regular emptying, servicing and cleaning.