Treatment Plants

What is a Domestic Treatment Plant?

For dwellings without access to mains drainage, and where a septic tank may not be suitable, a domestic treatment plant can provide reliable, efficient and environmentally-safe sewage disposal.

Once the sewage has been treated the resulting water can be released into a soakaway area or alternatively be sufficiently clean to run off into a watercourse.

They are particularly suited to:

  • Individual domestic properties
  • Small developments (less than 25 properties)
  • Commercial or industrial premises
  • The upgrade of existing septic tanks

Domestic treatment plants are normally buried underground, where they are encased in concrete. The hole is then backfilled, after which only the plant’s lid remains visible.


  • No mechanical or electrical components within the plant
  • Typically they are low maintenance with low or minimal running costs.
  • Low level visibility with a lockable child-proof pedestrian duty cover – safe for children and pets.
  • Controlled ventilation – minimises risk of odour nuisance.

General Binding Rules – What you need to know

The General Binding Rules are legally binding requirements that apply to anyone who owns or operates a domestic septic tank or small sewage treatment plant.

  • Your treatment plant must meet various minimum standards and conditions as set by the Environment Agency. If in doubt, give us a call and we can advise.
  • You need to check once a month for signs of pollution, such as sewage smells and signs that your sewage isn’t draining properly.
  • Remember to keep a record of any work you’ve had done on your system including when it was emptied, maintained or repaired.
  • You should also record details about any accidents or complaints relating to your system.
  • Older treatment systems that discharge directly to surface water, should have been replaced or upgraded by 1 January 2020.

Find out more about the General Binding Rules here >

Klargester Treatment Plant
Illustration of a Gravity Outlet Treatment Plant