Permits, air and water EWSNI
Trade effluent consents, water discharge permits and abstraction licences
Anything other than domestic sewage and clean rainwater that leaves your site as liquid needs permission. Trade effluent to the public sewer needs a consent from your water and sewerage company; discharges to rivers, estuaries, the sea or the ground need an environmental permit (or EASR authorisation in Scotland, or a consent in Northern Ireland); and taking more than 20 cubic metres of water a day from a river, well or borehole in England or Wales needs an abstraction licence.
At a glance
- Who must comply
- Any business discharging process water, wash water, cooling water, vehicle wash, food or chemical effluent, or contaminated site drainage; anyone abstracting water for business use.
- Thresholds
- No minimum for trade effluent to sewer. Abstraction: licence above 20 m³ a day in England and Wales; Scotland and Northern Ireland use their own EASR and licensing tiers.
- Next key date
- No fixed deadline: consents and permits are needed before the first discharge or abstraction, and water company trade effluent charges change each 1 April.
- Regulator
- Your water and sewerage company (sewer); Environment Agency, NRW, SEPA or NIEA (rivers, sea, groundwater and abstraction).
- Maximum penalty
- Discharging to sewer without consent: fine on conviction under the Water Industry Act 1991. Polluting controlled waters without a permit: unlimited fine, up to 5 years' imprisonment and uncapped civil penalties in England.
- Where to do it
- Trade effluent application to your sewerage undertaker; environmental permit or abstraction licence application to the regulator.
This probably applies to you if
- You run a food or drink plant, laundry, car or vehicle wash, printer, metal finisher, brewery, dairy, abattoir or chemical process with a drain
- Your site drainage could carry oil, silt, chemicals or detergents into a surface water drain, ditch or watercourse
- You discharge cooling water or treated effluent to a river, estuary or the sea
- You discharge to a soakaway or the ground, including from a private sewage treatment plant
- You abstract water from a river, lake, spring, well or borehole for process, irrigation, cooling or supply
Three routes, three permissions
| Where the liquid goes | Permission needed | Who issues it |
|---|---|---|
| Public foul sewer (trade effluent) | Trade effluent consent or agreement | Sewerage undertaker (for example Thames Water, Severn Trent, Dŵr Cymru, Scottish Water, NI Water) |
| River, stream, lake, estuary, sea, or surface water drain leading to one | Water discharge activity permit (England and Wales), EASR authorisation (Scotland), discharge consent (Northern Ireland) | Environment Agency, NRW, SEPA, NIEA |
| The ground, soakaway or infiltration system | Groundwater activity permit (England and Wales), EASR authorisation (Scotland), consent (Northern Ireland) | Environment Agency, NRW, SEPA, NIEA |
| Water taken from the environment | Abstraction licence (England and Wales), EASR authorisation (Scotland), abstraction licence (Northern Ireland) | Environment Agency, NRW, SEPA, NIEA |
Domestic sewage from toilets and kitchens goes to the sewer without consent. Uncontaminated roof rainwater can go to surface water drains. Everything else from a trade premises is trade effluent or a discharge and needs permission before it starts.
Trade effluent to the sewer
Under section 118 of the Water Industry Act 1991 (section 26 of the Sewerage (Scotland) Act 1968 and the Water and Sewerage Services (Northern Ireland) Order 2006) it is an offence to discharge trade effluent to a public sewer without the undertaker's consent. You apply with details of the process, volume, flow rate, composition and any pre-treatment. The consent sets limits on volume, pH, temperature, suspended solids, chemical oxygen demand, fats, oils, metals and prohibited substances, and gives the company the right to sample.
Charges follow the Mogden formula, which prices each cubic metre according to its volume, strength (chemical oxygen demand) and solids, so pre-treatment that reduces strength lowers the bill. Rates change every 1 April and are published in each company's charges scheme.
Watch out: fat, oil and grease traps, silt interceptors and pH correction are usually conditions of consent for food, hospitality and vehicle businesses. A blocked sewer traced back to your outlet brings both a breach of consent and clean-up costs.
Discharges to rivers, sea and groundwater
In England and Wales, a discharge to surface water or groundwater is a regulated activity under the Environmental Permitting Regulations 2016 unless an exemption or exclusion applies. Small, low-risk discharges (for example treated domestic sewage below 5 m³ a day to surface water, or 2 m³ a day to ground, outside sensitive areas) can be registered as exempt; most trade discharges need a standard rules or bespoke permit with limits, monitoring and sampling conditions, plus an annual subsistence charge. See our environmental permits guide for the application process and charges.
Site drainage counts. Surface water drains usually lead straight to a watercourse, so oil, silt, concrete washout, detergents or spillages entering them are a discharge without a permit and a pollution offence. Regulators expect interceptors, bunding, spill kits and a drainage plan.
In Scotland, discharges have been authorised under EASR since 1 November 2025 as general binding rules, registrations or permits depending on risk; former CAR licences converted automatically. In Northern Ireland, discharges to waterways and groundwater need a consent from NIEA under the Water (Northern Ireland) Order 1999.
Abstraction licences
| Nation | Threshold | Regime |
|---|---|---|
| England and Wales | More than 20 cubic metres a day | Abstraction licence under the Water Resources Act 1991 (full, transfer or temporary); environmental permitting integration is being phased in |
| Scotland | Tiered under EASR: general binding rules for the smallest abstractions, registration and permit for larger volumes | SEPA |
| Northern Ireland | Licence required for abstractions above the thresholds in the Water Abstraction and Impoundment (Licensing) Regulations (Northern Ireland) 2006 | NIEA |
Licences set annual and daily limits, conditions to protect flows and other users, and require returns of the volumes taken. Charges are based on the licensed volume, source and season. Abstraction licences in England and Wales are time-limited and must be renewed before expiry.
How to get the right permission, step by step
Map every outlet and intake
Draw the drainage plan: foul sewer, surface water, soakaways, interceptors and any abstraction points. Dye-test if you are unsure where drains go.
Characterise the effluent
Volume, flow pattern, pH, temperature, COD, suspended solids, fats, oils, metals and any hazardous substances, from sampling if necessary.
Apply to the right body
Trade effluent consent to the water company; discharge permit or EASR authorisation to the regulator; abstraction licence where you take more than the threshold.
Install the controls the consent requires
Grease traps, interceptors, balancing tanks, pH correction, sampling chambers and flow meters.
Monitor, sample and keep records
Meet the consent's sampling and reporting conditions, keep results and respond quickly to exceedances.
Penalties and pollution incidents
Discharging trade effluent to a sewer without consent, or breaching consent conditions, is an offence under the Water Industry Act with fines on conviction, and water companies can recover damage and clean-up costs. Causing or permitting a discharge to controlled waters without a permit is an offence under the Environmental Permitting Regulations carrying an unlimited fine and up to five years' imprisonment, and since December 2023 the Environment Agency can impose variable monetary penalties with no upper limit. Report any spill to the 24-hour pollution hotline on 0800 80 70 60; early reporting is taken into account in enforcement.
How it differs across the UK
- E England
Trade effluent consents from the sewerage undertaker under the Water Industry Act 1991; discharge and groundwater permits from the Environment Agency under the 2016 Regulations; abstraction licences above 20 m³ a day under the Water Resources Act 1991.
- W Wales
The same legal framework as England, with Dŵr Cymru Welsh Water (or Hafren Dyfrdwy) issuing trade effluent consents and Natural Resources Wales issuing permits and abstraction licences.
- S Scotland
Trade effluent consents from Scottish Water under the Sewerage (Scotland) Act 1968; discharges and abstractions authorised by SEPA under EASR since 1 November 2025, using general binding rules, registrations and permits.
- NI Northern Ireland
Trade effluent consents from NI Water under the Water and Sewerage Services (Northern Ireland) Order 2006; discharge consents under the Water (Northern Ireland) Order 1999 and abstraction licences under the 2006 Regulations, both from NIEA.
Key dates
-
Water company trade effluent charges and Environment Agency water charges change for 2027/28
Dates marked “Proposed” are announced or consulted on but not yet law. See the full deadlines calendar.
Penalties and enforcement
| Breach | Penalty | Applies in | |
|---|---|---|---|
| Discharging trade effluent to a public sewer without consent, or in breach of consent conditions | Fine on conviction (up to the statutory maximum summarily; unlimited on indictment) plus recovery of damage and costs | EW | Source |
| Causing or permitting a water discharge or groundwater activity without an environmental permit | Unlimited fine and up to 5 years' imprisonment on conviction; variable monetary penalty with no upper limit | EW | Source |
| Abstracting water without a licence or in breach of licence conditions | Fine on conviction under the Water Resources Act 1991 | EW | Source |
| Carrying on a water activity without an EASR authorisation | Fine up to £40,000 and/or 12 months on summary conviction; unlimited fine and/or 5 years on indictment | S | Source |
Compliance checklist
Where to do it: official services
-
Discharges to surface water and groundwater: environmental permits
Register or apply
When you need a permit or exemption for a discharge and how to apply. Environment Agency via GOV.UK E
-
Apply for a water abstraction or impounding licence
Register or apply
Licence types, the 20 cubic metre threshold and the application process. Environment Agency via GOV.UK E
-
Find your water company
Tool or calculator
Identify the sewerage undertaker whose trade effluent team you apply to. Ofwat EW
-
Water activities under EASR (Scotland)
Register or apply
General binding rules, registrations and permits for discharges and abstractions in Scotland. SEPA S
-
Regulating water discharges (Northern Ireland)
Register or apply
How to apply to NIEA for a consent to discharge to waterways or groundwater. NIEA (DAERA) NI
The law behind this
- Water Industry Act 1991, section 118 (consents for trade effluent) EW
- Water Resources Act 1991, Part II (abstraction and impounding) EW
- Environmental Permitting (England and Wales) Regulations 2016, Schedules 21 and 22 (water discharge and groundwater activities) EW
- Sewerage (Scotland) Act 1968, section 26 S
- Water (Northern Ireland) Order 1999 NI
Questions people ask
Do I need a trade effluent consent for a car wash or kitchen?
Yes. Vehicle wash water, commercial kitchen wash water and similar liquids are trade effluent and need consent from your sewerage undertaker before they go to the foul sewer, however small the volume. The consent will usually require a silt interceptor or grease trap and set limits on oil and solids. Discharging without consent is an offence under the Water Industry Act 1991.
How are trade effluent charges calculated?
Most companies use the Mogden formula, which charges per cubic metre based on reception and conveyance costs plus the strength of your effluent (chemical oxygen demand and suspended solids relative to the company's average sewage). Reducing volume and strength through pre-treatment lowers the bill. Rates are published in each company's charges scheme and change on 1 April.
Can I discharge cooling water to a river?
Only with an environmental permit (England and Wales), an EASR authorisation (Scotland) or a discharge consent (Northern Ireland). Clean cooling water discharges often qualify for a standard rules permit, but temperature, biocides and volume are controlled. Discharging without permission is a pollution offence even if the water appears clean.
When do I need an abstraction licence?
In England and Wales, when you take more than 20 cubic metres a day from a river, stream, canal, lake, spring, well or borehole; temporary and transfer licences cover short-term and non-consumptive uses. Scotland uses EASR tiers from general binding rules upwards, and Northern Ireland licenses abstractions above thresholds set in its 2006 Regulations. All regimes require you to record and report volumes.
What should I do if there is a spill into a drain?
Contain it with spill kits or drain covers, stop the source, and call the 24-hour pollution hotline on 0800 80 70 60 straight away, then inform your water company if it reached the sewer. Keep a record of what happened and what you did. Prompt reporting and good spill prevention are weighed heavily in any enforcement decision.
Terms used in this guide
- Trade effluent
- Any liquid produced in the course of a trade or industry at a premises, other than domestic sewage and uncontaminated surface water.
- Mogden formula
- The formula sewerage undertakers use to charge for trade effluent according to volume, strength (chemical oxygen demand) and suspended solids.
- Water discharge activity
- A discharge of poisonous, noxious or polluting matter, waste, trade or sewage effluent to inland or coastal waters, regulated by environmental permit in England and Wales.
- Groundwater activity
- A discharge of pollutants to ground that may reach groundwater, requiring a permit or exemption.
- Abstraction licence
- Permission to take water from a surface or underground source above 20 cubic metres a day in England and Wales.
Sources
- Discharges to surface water and groundwater: environmental permits, GOV.UK
- Water management: apply for a water abstraction or impoundment licence, GOV.UK
- Water Industry Act 1991, section 118
- Water Resources Act 1991, section 24
- Water activities under EASR, SEPA
- A new era for environmental permitting in Scotland, CMS (October 2025)
- Regulating water discharges, DAERA
- Environment Agency may use unlimited financial penalties, Law Library of Congress
Reviewed 14 October 2026. If you spot something out of date, email info@thamesenvironment.com.