What happens if you don’t empty your cesspit or septic tank?

In some rural areas of the UK, there is no mains sewage connection. Where this is the case, households rely on on-site sewage systems for waste management, which consist of either a cesspit or a septic tank. Read on to find out what happens if you do not empty your cesspit or septic tank.

The difference between a cesspit and a septic tank

Before examining the risks, it’s worth clarifying the difference between a cesspit and a septic tank. A cesspit is a sealed underground tank that holds waste, without treating it. Once full, the cesspit must be emptied by a licensed waste carrier. By comparison, a septic tank, consists of two chambers. Liquids are separated from solid waste and are allowed to drain away into a soakaway system. Like cesspits, septic tanks need to be emptied and serviced regularly to function correctly and efficiently. 

What happens if you don’t empty a cesspit?

A cesspit doesn’t treat waste, so it fills up relatively quickly. This is what happens if it is not emptied:

Overflow and flooding - once full, your cesspit will overflow and the only place the waste can go will be into your garden, driveway or into the local environment. This flooding will consist of foul-smelling and hazardous liquid.

Health risks – the overflow for the cesspit will be raw sewage which contains bacteria and pathogens. These pose a serious health risk to humans and animals who could be exposed without knowing if playing outside.

Environmental pollution – if the sewage overflow from a cesspit is allowed to enter a waterway, environmental regulations will be broken, and wildlife endangered. 

Fines and legal trouble - discharging untreated sewage is illegal. If your cesspit leaks, you will face fines or action from the Environment Agency.

What happens if you don’t empty a septic tank?

Septic tanks are slightly more forgiving than cesspits because they separate and partially treat waste However, they do still need regular desludging—usually every 12 months. This is what happens if you do not do this:

Blocked soakaway systems – if the solid waste is allowed to build up in excess of the capacity of the septic tank, it will block up the drainage field or soakaway, preventing proper wastewater dispersal.

Backups and smells - wastewater will back up into your toilets, sinks, and drains, and there will be strong, foul smells inside and outside your home.

The septic tank will fail - over time, if the tank is not de-sludged, it will become damaged or stop working completely. When this happens, you will need a new septic tank, with a replacement system costing thousands of pounds.

Contamination – a damaged system will harmful bacteria and pollutants into the ground, potentially affecting groundwater and any nearby wells.

How often should you empty a cesspit or septic tank?

•    Cesspits will need to be emptied every 4 to 8 weeks depending on their size and the household usage.

•    Septic tanks will generally need desludging annually but this can vary.

If you're unsure, a professional inspection can help, but keep an eye out for warning signs which include slow drains, gurgling pipes, or soggy ground around the tank.

Cesspit emptying and septic tank cleaning from Fortis Hire

In the UK, only registered waste carriers can empty cesspits and septic tanks. The Environment Agency issues licences to authorised waste carriers and at Fortis Hire, we hold an upper tier licence, offering cesspit emptying and septic tank cleaning as part of our portable toilet cleaning service. This gives you the peace of mind that your sewage systems will be emptied, cleaned and maintained to the highest standards, with all waste being removed and disposed of in line with current Government guidelines. 

Emptying a cesspit or septic tank may seem like an inconvenience, but the alternative is disruptive and expensive. For a regular service, or just a one-off clean, get in touch today. Call the team on 01525 643850 or send some details to sales@fortishire.co.uk for a no obligation quote.