Septic tanks and sewage treatment plants: what you need to do
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 鈥榩ublic foul sewer鈥�)
- it is not 鈥榬easonable鈥� to connect to the public foul sewer
- your sewage treatment system does not meet the 鈥榞eneral binding rules鈥�
- 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鈥檙e breaking the law if you operate without a permit when you need to have one.
Read the guidance on 鈥楧ischarges to surface water and groundwater鈥� to find out when you do not need a permit.
If you discharge sewage to ground
There are different forms depending on whether you鈥檙e 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 鈥楧ischarges to surface water and groundwater鈥� 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:
- before 1 January 2015 - fill in part B6.6 of the environmental permit form
- on or after 1 January 2015 - fill in part B6.5 of the environmental permit form
If you discharge more than 2 cubic metres per day, there are different forms depending on how much you discharge. If you:
- discharge between 2 and 15 cubic metres per day - fill in part B6.5 of the environmental permit form
- discharge over 15 cubic metres per day - read the guidance on 鈥楧ischarges to surface water and groundwater鈥� to find out how to apply for a bespoke permit
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 鈥楧ischarges to surface water and groundwater鈥� 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鈥檒l need another kind of permit. There are different forms depending on how much you discharge. If you:
- discharge up to 20 cubic metres - fill in part B6.5 of the environmental permit form
- discharge over 20 cubic metres - read the guidance on 鈥楧ischarges to surface water and groundwater鈥� to find out how to apply for a bespoke permit
Before you start
You need:
- to for your septic tank or treatment plant and the point where it discharges
- to calculate the largest amount you鈥檙e likely to discharge - use the sewage discharges calculator for domestic properties
If you have a commercial property then work out your discharge using British Water鈥檚 Flows and Loads guidance document from the .
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 拢125.
If your site is another type of organisation
You鈥檒l pay a different fee depending on whether you鈥檙e 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) | 拢2,647 |
| Over 5,000 litres (5 cubic metres) and up to and including 15,000 litres (15 cubic metres) | 拢4,269 |
| Over 15,000 litres (15 cubic metres) | 拢10,062 |
| Size of discharge per day | Fee for discharging to surface water |
|---|---|
| Up to and including 5,000 litres (5 cubic metres) | 拢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 | 拢1,229 |
| Over 5,000 litres (5 cubic metres) and up to and including 50,000 litres (50 cubic metres) | 拢6,463 |
Habitats assessment fee
If you鈥檙e 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 拢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
Annual fee
There鈥檚 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) | 拢247 |
| Over 5,000 litres (5 cubic metres) and up to and including 20,000 litres (20 cubic metres) - with operator self monitoring | 拢813 |
| Over 5,000 litres (5 cubic metres) and up to and including 20,000 litres (20 cubic metres) - without operator self monitoring | 拢888 |
| Over 20,000 litres (20 cubic metres) and up to and including 50,000 litres (50 cubic metres) - with operator self monitoring | 拢1,253 |
| Over 20,000 litres (20 cubic metres) and up to and including 50,000 litres (50 cubic metres) - without operator self monitoring | 拢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鈥檒l 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.