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Pollution control

Pollution control authorisations

We are now able to accept pre-application proposals, new applications, variations, transfers and surrenders covering abstractionsimpoundments and hydro schemes.

We would strongly encourage pre-application enquiries prior to submitting applications.

What should you do now?

Email application forms along with supporting information to

Email pre-application proposal and supporting information to

Submit enquiries about General Binding Rules, existing authorised sites and maintenance via our online form: Contact us

Pollution control

Any activity likely to cause pollution to the water environment must be carefully controlled and managed to prevent damage.

Pollution control is managed by the Water Environment (Controlled Activities) (Scotland) Regulations 2011 – more commonly known as the Controlled Activity Regulations (CAR) – and their further amendments. Our introduction to the regulations summarises the main features of the regulations.

The aim of pollution control

The aim of pollution control is to protect the water environment from any potential harm caused by discharges of pollutants.

There are a variety of ways in which discharges of pollutants – including waste products, chemicals, oil and sewage – can be introduced into the water environment.

Typically, discharges will be made directly to water. However, the regime also includes disposals to land, such as waste sheep dip and pesticides, which have the potential to cause groundwater pollution.

Point source discharge means a release of effluent or other matter to the water environment or land, via a pipe or outlet.

This includes:

  • sewage and trade effluent;
  • surface water discharges from urban areas;
  • abandoned mine discharges.

Diffuse pollution is the release of potential pollutants from a range of activities that individually may have no effect on the water environment, but at the scale of a catchment can have a significant impact. It arises from land use and management, and includes livestock grazing, cultivation of land, run-off from urban areas and forestry activities.

It is a requirement for new developments with surface water drainage discharging to the water environment that such discharges will pass through sustainable urban drainage systems (SUDS).

In the majority of instances, the discharge from SUDS will be authorised under general binding rules (GBRs), however large sites may require a licence to discharge. In addition to CAR, regulatory controls on the storage of oil also exist. The Water Environment (Oil Storage) (Scotland) Regulations, more commonly known as the Oil Storage Regulations (OSR), came into force in 2006. The storage of oil is a controlled activity, authorised by compliance with the OSR.

Do the regulations apply to me?

If your activity involves any of the following, you will require some form of authorisation from us:

  • Sewage and organic effluents
  • Fish farms
  • Inorganic effluents
  • Thermal effluents
  • Surface water drainage
  • Waste sheep dip and waste pesticides
  • Storage and application of fertilisers
  • Keeping of livestock
  • Cultivation of land
  • Discharge of surface water run-off
  • Construction and maintenance of roads and tracks
  • Application of pesticide
  • Operation of sheep dipping facilities

The level of authorisation required is dependent on the effect that the activity will have on the water environment:

  • General binding rules (GBRs) – activities that are considered of low risk to the environment are covered by a GBR. You will not have to contact us or incur any charges, although you will have to follow a set of rules.
  • Registration – activities that pose a low individual risk, but may collectively affect the environment, will need a registration, require you to apply to us and incur a fee. You will not, however, incur an annual subsistence charge.
  • Licence – activities that pose a moderate to high risk to the environment will either be a simple licence or – for activities that need a more complicated environmental assessment – a complex licence. A licence depends on the identification of a ‘responsible person’, who must ensure compliance with the conditions of the licence. In both cases, an application charge will apply and the activity may also be subject to an annual subsistence charge.

We do not regulate point source discharges from vessels in coastal or transitional waters – these are controlled by the Maritime and Coastguard Agency as set out in the Merchant Shipping Act 1995.

What do I need to do?

Find out if your activity requires authorisation

Read the relevant chapter in our CAR practical guide to discover whether or not your activity is subject to regulation:

  • If your activity falls under a general binding rule (GBR), you will not have to do anything.
  • If your activity meets the criteria as described in our practical guide, you can apply for a registration online.
  • If your activity meets the criteria as described in our practical guide, you must apply for a licence either electronically or by post. Our CAR licence applicant guidance provides guidance and information on the licence application process.

Determine the cost of your application

Our charging scheme guidance will advise on the estimated cost the application and whether a subsistence (annual) fee applies.

A full list of all activities that do not require a charge can be found in Annex II of our charging scheme guidance.

Complete your application form before returning it to us by email by post or online (registration only).

We have 30 days to assess an application for registration and four months for a licence.

During this time, we can ask for more information from the applicant, request that they advertise their proposals publicly or make provision for public consultation and feedback. If this is necessary, the response time period can be paused.

Apply for a registration or licence online or by post

You can apply online if you want to register an existing septic tank or other private sewage treatment system.


Alternatively, you can complete a registration form for your specific activity and email pre-application enquiries to or applications along with supporting information to

Making a change to an existing registration

Please complete our form detailing a variation to an existing CAR registration and return it to us either by email or by post to the SEPA Registry address detailed on the form.


You will need to send an application either by email or by post if you require either a simple or a complex licence.

The CAR licence applicant guidance provides all available guidance and information on the application process.

You need to complete two application forms:

  • A universal application form which asks for general information about your activity or activities – our guidance will provide you with help and advice on completing the form.
  • A specific application form which provides us with more detailed information about your activity or activities – our guidance will provide you with help and advice on completing the form.

Making a change to an existing licence

Data returns for Sewage Treatment Works and Sewer Networks

Please visit our Environmental data pages for more information and details on how we are managing data returns at this time. 

Licences for discharges from only the larger sewage treatment works require the operator to submit annual flow data returns, normally by 31 January.

Flow monitoring at STWs and on the sewer network consists of two types – measurement of flows and recording of storm overflow events. The recording and reporting of flows and overflow events provides an important source of information for SEPA.

Further information on the details that require to be submitted can be found in your discharge licence.

Flow data returns should be provided by email in Excel format to us using the online contact form, as specified in section 2.3 of the document CAS-G-004 (Flow Recording and Flow Reporting at STWs and on the Sewer Network). Annexes 1, 2 (if applicable) and 3 of this document provide examples of the data return format. Template data returns forms are available below:

If you have any questions regarding any aspect of compliance with your licence conditions, please contact us.

Compliance with regulations

Operators are expected to uphold the conditions of their registration or licence and we have powers to withdraw your authorisation if you fail to meet its conditions.

Even after an authorisation has been granted, we can, if necessary, move activities between registration and licences, or from GBR to registration to licences in order to protect the water environment.

If you do not agree with the conditions and requirements imposed by a CAR authorisation or notice, you can make an appeal directly to the Scottish Government. The submission of an appeal does not suspend the operations of all authorisations or notices and its conditions.

Help, advice and more information

If you require any further help or advice at any stage during the application process, please contact us.