Septic Tank, Cesspit or Treatment Plant: Which Do You Have?
How to tell the difference between the three main private drainage systems — and why it matters when arranging emptying.
The quickest way to get the right operator and quote is to identify what type of private drainage system serves your property. If you are unsure, the comparison form allows you to say so.
Septic tank
A septic tank separates solids from wastewater. The liquid normally passes onward for further treatment, commonly through a drainage field. It still needs periodic desludging to stop solids affecting the rest of the system.
Cesspit or cesspool
A cesspit is a sealed storage tank. It does not discharge liquid to a drainage field, so it fills and must be emptied much more frequently. A missed empty can become urgent quickly.
Sewage treatment plant
A treatment plant uses a mechanical or biological process to treat wastewater before discharge. It needs routine servicing and desludging, but a warning light, smell or poor drainage may point to an issue that emptying alone will not fix.
Clues around the property
- Installation paperwork, service records or a previous invoice may name the system.
- A control panel or alarm is a strong sign of a treatment plant.
- Frequent tanker visits often indicate a cesspit.
- A drainage field or soakaway may indicate a septic tank or treatment plant.
If you are still not sure
Do not guess. Choose “Not sure”, describe the cover, alarm or visible equipment, and add any details from the property paperwork. A suitable operator can ask the right follow-up questions.