What you must do
If you pollute water, you are very likely to be committing an offence.
Discharge consent and authorisation
Only drain clean, uncontaminated water to the surface water drainage system.
You must get permission from your water company and sewage company or authority before connecting to the public drainage system. If you are a tenant you may need your landlord’s permission to connect to a private surface water drain.
Water UK: Water and sewerage operators
You must get prior written authorisation from your environmental regulator if you intend to discharge anything other than clean, uncontaminated surface water to surface waters or ground waters. You must comply with any conditions in the authorisation. This authorisation could be in the form of:
- a discharge consent
- a groundwater authorisation
- an environmental permit (England and Wales)
- a pollution prevention and control (PPC) permit (Northern Ireland)
- an integrated pollution control (IPC) authorisation or pollution prevention and control (PPC) permit (Scotland)
- an authorisation under the Controlled Activity Regulations (CAR) in Scotland.
You must comply with all of the conditions of your authorisation. If you don’t comply with the conditions you may be prosecuted and fined.
In Scotland, certain discharges to surface waters are automatically authorised by General Binding Rules (GBR) providing these rules are complied with. In such cases, you do not need to apply for authorisation from SEPA.
Water pollution
Discharges to public sewer
You must get permission from your water company or water authority before connecting to their drainage system.
You are allowed to connect sewage from domestic facilities, ie toilets and basins, to a public foul sewer (pipe which collects foul water only) or to a public combined sewer (pipe which collects both foul and surface water drainage). However, if the drainage facilities include a separate surface water sewer (pipe which collects surface water drainage only), you must never discharge sewage into it.
Water UK: Water and sewerage operators
Before you release trade effluent into a public foul sewer you must have a trade effluent consent or enter into a trade effluent agreement with your water company or water authority. Once you have a consent, you must comply with its conditions.
Trade effluent - discharges to sewers
In England and Wales, Source Protection Zones (SPZs) have been set up to protect groundwater that is extracted from boreholes or springs for public water supply.
Environment Agency: Groundwater source protection zones
In Northern Ireland and Scotland, Source Protection Zones have not been defined. To find out if you are in an area where groundwater is particularly vulnerable, contact your environmental regulator.
Contact your environmental regulator
If you have a septic tank or package treatment plant you should read Pollution Prevention Guideline (PPG) 4.
PPG 4 Treatment and disposal of sewage where no foul sewer is available (Adobe PDF - 244KB)
Good practice
The best environmental option will normally be to discharge trade effluent and sewage to the public foul sewer.
Make sure you have an up-to-date and accurate drainage plan of your site. This will help you identify the locations of all the drains and sewers and where they lead.
Colour code your drainage system by painting manhole covers, gullies and grills using a recognised colour coding system, for example blue for surface water drains and red for foul water drains. This will help you to identify which system you are discharging to and also the destination of any spill.
Store all chemicals in an area where spills can be contained. This should be within an impermeable bund. A bund is secondary containment area that holds liquids if the main containers leak or break.
If you have one oil storage container in a bund, the bund must be able to hold of 110% of its volume.
If you have more than one container in a bund, the bund must be able to hold whichever of the following is greater:
- 25% of the total volume of the containers
- 110% of the largest container’s volume.
Supervise deliveries of materials and fuels to your site. Clearly label tanks with their contents and storage capacity and provide a method for measuring the amount in the tank. This will reduce the risk of overfilling and spills.
Prepare a pollution incident response procedure for dealing with spills and use it in conjunction with your drainage plan. Train your staff so that they are aware of the procedure. Report all pollution incidents immediately to the incident hotline on 0800 80 70 60 to make sure that any pollution is tackled as soon as possible.
PPG 21 Pollution incident response planning (Adobe PDF – 318KB)
Make sure that you have absorbent materials and other containment equipment, eg a ‘spill kit’, suitable for the type and quantity of fuel, oil and chemicals you store and use on site. Make sure that the equipment is easily accessible and placed close to where it might be needed. Make sure that you replace materials after use.
