Septic tanks and sewage treatment plants: what you need to do

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Apply for a permit

Only apply for a permit after you have checked:

  • your sewage system is not already connected to the mains sewer (the ‘public foul sewer’)
  • it is not ‘reasonable’ to connect to the public foul sewer
  • your sewage treatment system does not meet the ‘general binding rules’
  • you cannot change your system to meet the general binding rules

The Environment Agency will not give you a permit if they think it is reasonable for you to connect to the public foul sewer or if you could meet the general binding rules by making changes to your system.

You’re breaking the law if you operate without a permit when you need to have one.

Read the guidance on ‘Discharges to surface water and groundwater’ to find out when you do not need a permit.

If you discharge sewage to ground

There are different forms depending on whether you’re in a groundwater protection zone (SPZ1) or not.

Outside an SPZ1

If your sewage is both:

  • classed as domestic
  • a discharge of between 2 and 15 cubic metres per day

You need to fill in part B6.5 of the environmental permit form.

If your sewage is either:

  • not classed as domestic
  • a discharge of over 15 cubic metres per day

Read the guidance on ‘Discharges to surface water and groundwater’ to find out how to apply for a bespoke permit.

Inside an SPZ1

All sewage discharges within an SPZ1 require a permit.

If you discharge less than 2 cubic metres per day, there are different forms for systems that were installed:

If you discharge more than 2 cubic metres per day, there are different forms depending on how much you discharge. If you:

If you discharge sewage to a surface water

If your sewage is both:

  • classed as domestic
  • a discharge between 5 and 20 cubic metres per day

Read the guidance on ‘Discharges to surface water and groundwater’ to check if you can apply for a standard rules permit.

If your sewage is either:

  • not classed as domestic
  • not eligible for a standard rules permit

You’ll need another kind of permit. There are different forms depending on how much you discharge. If you:

Before you start

You need:

If you have a commercial property then work out your discharge using British Water’s Flows and Loads guidance document from the British Water website.

Application fee

The fee you pay depends on whether your site is:

  • a domestic household - includes self-catering and holiday let properties, unless you pay business rates on these
  • a charity - either a registered charity or has a HM Revenue and Customs (HMRC) charity number
  • another type of organisation such as a campsite, pub, shop or holiday let that pays business rates

If your site is a domestic household or charity

The application fee to discharge up to and including 5,000 litres (5 cubic metres) per day either to ground or to surface water is £125.

If your site is another type of organisation

You’ll pay a different fee depending on whether you’re discharging to ground or to surface water.

Size of discharge per day Fee for discharging to ground
Up to and including 5,000 litres (5 cubic metres) £2,647
Over 5,000 litres (5 cubic metres) and up to and including 15,000 litres (15 cubic metres) £4,269
Over 15,000 litres (15 cubic metres) £10,062
Size of discharge per day Fee for discharging to surface water
Up to and including 5,000 litres (5 cubic metres) £2,434
Over 5,000 litres (5 cubic metres) and up to and including 20,000 litres (20 cubic metres) - for a standard rules permit £1,229
Over 5,000 litres (5 cubic metres) and up to and including 50,000 litres (50 cubic metres) £6,463

Habitats assessment fee

If you’re applying for a permit in certain protected sites, the Environment Agency might need to carry out a habitats assessment.

Protected sites include:

  • a European Site within the meaning of the Conservation of Habitats and Species Regulations 2017
  • a site referred to in the National Planning Policy Framework 2023 as requiring the same assessment as a European Site
  • a site of special scientific interest within the meaning of the Wildlife and Countryside Act 1981
  • a marine conservation zone within the meaning of the Marine and Coastal Access Act 2009

The habitats assessment fee is £2,035.

You do not need to pay the fee if both of the following apply:

  • your site is a domestic household or charity
  • your site discharges no more than 5,000 litres (5 cubic metres) of domestic sewage per day

Find out how to pay the fee.

Annual fee

There’s an annual subsistence fee for sites that are not domestic households or charities.

Size of discharge per day Fee
Up and including 5,000 litres (5 cubic metres) £247
Over 5,000 litres (5 cubic metres) and up to and including 20,000 litres (20 cubic metres) - with operator self monitoring £813
Over 5,000 litres (5 cubic metres) and up to and including 20,000 litres (20 cubic metres) - without operator self monitoring £888
Over 20,000 litres (20 cubic metres) and up to and including 50,000 litres (50 cubic metres) - with operator self monitoring £1,253
Over 20,000 litres (20 cubic metres) and up to and including 50,000 litres (50 cubic metres) - without operator self monitoring £1,592

How long it takes

The Environment Agency will check your application and let you know if you need to send more information.

Once your application is confirmed as complete you should expect it to take at least 4 months to get a decision. The Environment Agency will tell you if your application will take longer.

If your application is refused

If your application is refused, you’ll be told why and how you can appeal.

Complying with your permit

See the guidance on how to comply with your permit, including maintenance, record keeping and pollution reporting requirements.

Get help with your application

If you are sure you need a permit you can ask the Environment Agency for advice before you apply.

View a printable version of the whole guide

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