Use Code SEWAGE5 for 5% Off Spare Parts Orders Over £250

Septic Tanks

Septic tanks are designed to connect to a drainage field (soakaway), which is a series of slotted pipework constructed underground.

Sewage enters the tank and the solids settle to the bottom. The liquid rises to the top, making contact with oxygen which starts to break down the organic matter biologically. The liquid still contains sewage, but in small enough particles to be carried into the soakaway, which then drains into the soil for further anaerobic treatment.
Browse our extensive range of septic tanks below, and if you have any questions, check out the Septic Tanks section on our Direct Drainage Knowledge Base.
If you need any more information, give our team a call on 01388 537050 or email sales@direct-drainage.co.uk
Customers are responsible for arranging offloading, HIAB options are available for certain products upon request. Please let us know when ordering of any restrictions regarding delivery. Please note we can only deliver septic tanks to the mainland UK.
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What is a Sewage Treatment System?

A sewage treatment system for private properties processes wastewater from homes and businesses that are not connected to mains drainage. It removes solids, organic matter, and harmful bacteria through physical, chemical, and biological treatments, ensuring that the treated effluent meets environmental standards. Typically housed in a sewage treatment plant, these systems allow safe discharge into natural water sources, helping to prevent water pollution and comply with regulations for off-mains drainage solutions.

How do Sewage Treatment Systems work?

Sewage treatment systems use a combination of mechanical and biological processes to remove contaminants, solid waste, organic matter, pathogens, grease, and oil from sewage water and industrial wastewater. Once treated, the resulting effluent meets the required quality standards for safe discharge into natural watercourses. Common treatment methods include rotating biological contactors (RBC), aeration, sedimentation, and filtration.


There are many treatment system designs, but we only supply BS EN-certified systems that comply with industry regulations and come from trusted manufacturers known for reliable performance and excellent customer service.

How to Choose the Right Wastewater Treatment Tank for Your Needs

Selecting the right wastewater treatment tank depends on factors like local regulations, property size, soil conditions, household water usage, and the type of treatment system needed. If you are unsure what system you need give us a call on 01388 537050.