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Septic tanks and private sewage treatment systems

If you're not connected the the public sewer, you probably use a private sewage treatment system, such as a septic tank or package treatment plant. This might only deal with the sewage and wastewater from your property, or it could be from several properties.

This type of system discharges to land or water and could cause pollution. By law, it must be registered.

If you're not sure if your treatment system is already registered, you can ask us to check. If it is already registered and you register again, we can't offer a refund.

Registering a small sewage discharge

You can apply to register a small sewage discharge if:

  • the discharge is from up to 10 domestic properties; or
  • the discharge is from non-domestic properties that serve a population equivalent (p.e.) of up to 50.

If your discharge is larger than this, you will need to apply for a licence. Please read how to apply for a licence to discharge sewage effluent.

All registered activities are subject to conditions. This is to prevent pollution.

When you register a small sewage discharge, you must meet the conditions of your registration. This includes properly maintaining your private sewage treatment system. To find out more about the conditions that apply to small sewage discharge registrations, please read our registration guidance.

You must pay a registration fee when you apply for a registration. The registration fee for a small sewage discharge is £185.

How to apply

You can apply to register an existing small sewage discharge or apply to register a new one.

Registering an existing small sewage discharge

An existing small sewage discharge is a discharge from a treatment system that is more than two years old.

You can apply to register online if your discharge is from nine properties or less.

If your existing discharge is from 10 properties, you can't apply online. You should apply for a registration by completing an application form and emailing it to our Registry Team.

If your existing discharge is from more than 10 properties, you will need to apply for a licence. Contact us by emailing the Water Permitting Team to discuss.

An untreated discharge is a discharge that doesn't go through any type of treatment before discharge to land or water. If your existing discharge is untreated, you should contact us by emailing the Water Permitting Team.

Registering a new small sewage discharge

A new small sewage discharge is a discharge from a treatment system that is less than two years old or is not yet in use (for example, if you're still in the planning stage of building a house or business).

New sewage discharges must be connected to the public sewer system where possible. If you have a new sewage discharge, you should contact Scottish Water for more information about connecting to the public sewer.

If you can't connect to the public sewer, you will need to apply to SEPA to register your discharge.

You can apply to register online if your discharge is:

  • from up to 10 domestic properties; or
  • from a combination of domestic and non-domestic properties that serve a population equivalent (p.e.) of up to 50.

Our online application service will help you decide what type of treatment system you need.

Read our registration guidance before starting any application.

If your discharge is grey water or liquid from a composting toilet, you can't apply online. Read composting toilets and grey water for more information.

If you are unable to register using our online service

It's quicker and easier to register your sewage discharge online. If you can't register using our online service, you can still apply by completing an application form and emailing it to our Registry Team.

If our service told you that your registration could not be completed online, read our registration guidance for information about what to do next.