What is The Difference Between a Septic Tank and Cesspit?

What is the difference between a septic tank and cesspit?

A common question we get asked, is “what is the difference between a cesspit and septic tank?”

Whilst both a cesspit and a septic tank perform the same task, which is dealing with wastewater, there are some differences between how they function. This post will explain some of the differences and some of the common issues so you can make a more informed decision on whether a septic tank or cesspit system is more suitable for your requirements.

What is a septic tank?

A septic tank is an underground sedimentation tank used to treat wastewater from properties that are not connected to the main sewer system and are often constructed from fibreglass, concrete or polyethylene plastic.

They contain multiple chambers to collect and process wastewater. The wastewater enters a first chamber where the solids are able to settle and decompose. While the remaining liquid flows into a second chamber and through to the soakaway.

Septic tank systems use a treatment process, allowing the treated wastewater to drain away into a stream or soakaway and should only require emptying when the solids levels have built up within the tank, typically every two years or so.

Although a septic tank doesn’t require as much maintenance as a cesspit, it is advisable to have your tank periodically services to ensure it is in full working order.

Once thing worth noting is that a septic tank relies of bacteria to decompose waste. This natural process can be disrupted by flushing chemicals such as bleach and other cleaning products, so we’d recommend only using problems that are deemed safe for use with septic tank systems.

What is a cesspit?

A cesspit (or cesspool) on the other hand is effectively an underground storage tank for your wastewater and requires much more regular emptying as they don’t “process” the wastewater like a septic tank does. They simply collect waste liquids and solid and require much more maintenance compared to a septic tank.

Cesspits are often used for temporary sewage systems, such as on construction sites or in locations where they’ll be used infrequently, so they won’t need to be emptied as regularly.

Cesspits are more suited to commercial applications than residential, due to the more regular maintenance schedule a cesspit requires. For example, you would commonly find a cesspit at a campsite due to the chemical toilet waste which would disrupt the bacteria in a septic tank system.

What is the difference between a septic tank and cesspit?

Which is better, a cesspit or septic tank?

Generally speaking, if you live in a home without a main connection to the local sewer system, a septic tank if the preferred option. However, if your soil fails soakaway tests and don’t have a surface drain where the sewage can be deposited to, a cesspit would be your best option.

What are the common issues with cesspits and septic tanks?

As cesspits and septic tanks are buried underground, they can often get overlooked but both do require regular maintenance to ensure they are functioning correctly.

If you have a cesspit or septic tank installed on your property and have noticed that your toilet is starting to gurgle, or perhaps your bath or sinks aren’t draining as quickly as they once were, or have noticed a pungent smell outside, this could indicate that you have a problem.

The first thing to check is whether your septic tank or cesspit needs emptying. As we mentioned before, a cesspit will require much more regular emptying than a septic tank, in most cases this would be performed monthly, so if you’ve forgotten to get your septic tank emptied for a while, this is most likely the cause of the issue.

A septic tank by comparison doesn’t require emptying as frequently. Whilst we’d recommend getting your septic tank emptied regularly, as long as the bacteria is doing its job and your septic tank is functioning correctly, you may be able to get away with a longer period between empties. Again, if it’s been a year or two since the last time you had your septic tank emptied, this could be the cause of most of your problems.

If you know for a fact your cesspit or septic tank has been emptied recently, another cause of problems, is incorrectly placing things down your drains that shouldn’t be there. Such as nappies, wet wipes, used cooking oil etc. If you’ve flushed something that you shouldn’t have, then you could have a blockage which will need to be dealt with by an experienced drain clearance company.

Another issue that you can encounter is leaking. A leaking cesspit or septic tank cause lead to rather pungent smells and the contamination of your garden or property.

Leakages can be caused by a number of issues. It could be because the tank was installed incorrectly, tree roots penetrating the tank, or simply general age-related issues. Whilst a cesspit or septic tank will often give many years of use, nothing lasts forever and will eventually need replacing.

Final Thoughts

If you need assistance diagnosing an issue with your septic tank or cesspit, or simply need to book an appointment to have your tank pumped, here at Flo-Well we have a wealth of experience and have a fleet of drainage tankers standing by to help with your septic tank emptying and cesspit emptying needs. Please contact our team of friendly drainage professionals for assistance.