When you need an environmental permit to discharge liquid effluent or waste water to surface water or the ground, and how to apply.
You may need an environmental permit if you discharge liquid effluent or waste water:
- into surface waters, for example, rivers, streams, estuaries, lakes, canals or coastal waters – known as ‘water discharge activities’
- into or on the ground, such as spreading waste sheep dip, or discharging treated sewage effluent to ground through an infiltration system – known as ‘groundwater activities’
Waste water includes:
- poisonous, noxious or polluting matter
- polluting substances
- waste matter
- trade or sewage effluent
If your water discharge or groundwater discharge is part of a waste operation, installation or mining waste operation, you can make the discharge part of your installation permit or waste or mining waste permit.
You’re breaking the law if you operate without a permit when you should have one.
Check if the waste water is domestic sewage or trade effluent
As part of your permit application, or to know whether your activity qualifies for an exemption, you must classify your waste water. Read more about when your waste water is classed as domestic sewage.
When you do not need a permit
You do not need a permit:
- to discharge uncontaminated water, such as clean rainwater from roofs (as explained in groundwater protection position statement G12) or from small areas of hardstanding to surface water
- to discharge uncontaminated water collected from public roads and small parking areas (that’s been through a properly maintained oil separator) to surface water
- for certain low risk groundwater activities, known as groundwater activity exclusions
- for a closed-loop heat exchanger
You do not need a permit to discharge to an enclosed lake or pond. This means a lake or pond in which all of the following apply:
- it contains water throughout the year, other than in extreme weather conditions
- it does not have an outfall that connects it to a watercourse, or has an outfall that only discharges in extreme weather conditions
- it is sealed or lined to prevent water draining into the ground or soaking into the surrounding soil
You must use appropriate pollution prevention measures to make sure your discharge does not cause pollution.
For discharges of uncontaminated water (such as rainwater) from excavations, you do not currently need an environmental permit if you meet the requirements of the temporary dewatering from excavations to surface water regulatory position statement.
The Environment Agency’s approach to groundwater protection is explained in its groundwater protection position statements.
Exempt water discharge and groundwater activities
You will not need an environmental permit for the following activities if you meet certain conditions. Check if you’re exempted from requiring an environmental permit:
- to discharge domestic sewage if you meet the general binding rules for discharges to a surface water or the general binding rules for discharges to ground
- for discharging substances as part of a groundwater tracer test or remediation scheme
- for cutting vegetation in or near inland freshwaters
Check the guidance for open-loop heat pump systems to find out if you:
- need a standard rules permit or bespoke permit for these systems
- can operate them under an exemption or regulatory position statement
Discharges in sewered areas
You should discharge your waste water to the public foul sewer whenever it’s reasonable to do so. You do not need an environmental permit to do this.
To find out if there is a public foul sewer near your property, contact your local water company. You may also need to ask your neighbours if their properties are connected to the public foul sewer, as water companies’ maps may not show all their sewers near you.
You must check with your sewerage undertaker (usually your local water company) before you:
- make a new connection to the public sewer
- discharge anything other than domestic sewage
Permits in sewered areas
The Environment Agency will not give you a permit for a private sewage treatment system if it’s reasonable for you to connect to the public sewer.
Their assessment of what is reasonable takes into account:
- the comparative costs of connecting to public sewer and installing a private sewage treatment system
- any physical barriers that would prevent you connecting to the public sewer
- any environmental benefits that would arise from installing a private sewage treatment system such as the reuse of treated effluent
They also consider how close you are to a public foul sewer. It’s likely that they will consider it reasonable for you to connect to a public foul sewer in the following scenarios.
For a single domestic property
If any boundary of the premises that your system serves is within 30 metres of the public foul sewer.
If you’re building a development of more than one property
If the distance from the boundary (of the premises that your system serves) to the nearest public foul sewer is less than the number of houses multiplied by 30 metres.
Example If there are 3 properties then it’s if the distance is less than 90 metres (3 × 30 metres).
In some cases, the Environment Agency may ask you to consider connecting to the public foul sewer if it’s further away.
If some or all of your discharge is from anything other than domestic properties
If there are any public foul sewers within the distance from the boundary of the premises that your system serves, calculated using the following method.
Divide the maximum volume in cubic metres that you want to discharge from those other premises by 0.75 (1 cubic metre is 1000 litres). Multiply the result by 30 metres. This will give you a result in metres.
Example A discharge of 1.2 cubic metres divided by 0.75 gives 1.6, which multiplied by 30 gives a result of 48 metres. So, in this example, it’s if there is a public foul sewer within 48 meters.
If you cannot connect to a public foul sewer
If there is a good reason why you cannot connect to the public foul sewer (for example, if there is a river or a railway line in the way) then you must apply for a permit. You must provide evidence to justify this when you apply – this is explained in the guidance for part B6 of the application form.
The Environment Agency will decide whether to allow you to use a private sewerage system or whether you should connect to the public foul sewer instead.
