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  • Private sewage treatment system registration variation guidance
  • Private sewage treatment system registration variation guidance

Private sewage treatment system registration variation guidance

If there is a change relating to a registered sewage discharge, you may need to apply to SEPA for a variation of the registration.


If you want to add an additional property to the registration, contact waterpermitting@sepa.org.uk to discuss this with us

You do not need to apply for a variation to a registration if

  • extra rooms or a toilet are being added to a domestic property;
  • the population equivalent (p.e.) is being reduced; or
  • the type of sewage treatment is improving e.g. a septic tank is being replaced by a package treatment plant (PTP), and the registration
  • does not state what type of treatment is required; or
  • does state the type or standard of sewage treatment, but the registration does not need to be amended to reflect this change.

For example, a septic tank is being replaced by a package treatment plant (PTP). A registration has been granted for this “discharge of sewage effluent treated by a septic tank or to a standard that is better than that provided by a septic tank”. This registration does not require an amendment as a package treatment plant (PTP) treats effluent to a standard that is better than a septic tank.

You need to apply for a variation to a registration, but there is no fee, if:

  • the name or address of a property specified in the registration is changing; or
  • the type of sewage treatment system is improving and the registration needs to be amended to reflect this change.

For example, a registration has been granted for the “discharge of sewage effluent treated by a septic tank”. The septic tank is being replaced by a package treatment plant (PTP). The registration requires an amendment as sewage effluent will now be treated by a package treatment plant (PTP) and not a septic tank.

You need to apply for a variation to a registration, and pay an application fee of £129.50 (correct from 1st April 2024 until 31st March 2025), if the registration needs to be changed due to:

  • the discharge outfall location moving;
  • a change to where the sewage effluent is discharging to; (for example, soakaway to watercourse or vice versa)
  • an increase in the population equivalent (p.e.) of a non-domestic property;
  • a reduction in the type or standard of sewage treatment.
    To apply to vary a registration, complete this form and submit with the application fee, if required.
    SEPA will consider the application and determine whether to grant the variation.

Licence required

If you propose to increase the size of your discharge, so that it will be from more than 10 domestic properties or more than 50 p.e., you will need to apply for a licence. Contact waterpermitting@sepa.org.uk
If you wish to make a change in relation to a licence, contact waterpermitting@sepa.org.uk to discuss with us.