Agriculture & Farming Environmental compliance

Get a water discharge permit

How to get an environmental permit for discharging liquid effluent or waste water to surface water or groundwater. Covers standard rules and bespoke permits, groundwater protection, monitoring requirements, and the difference between environmental permits and trade effluent consent.

UK-wide
Guide summary

You need an environmental permit from the Environment Agency if your business discharges liquid waste or effluent into surface water (like rivers or the sea) or groundwater. This includes trade effluent, sewage, or contaminated run-off. Applying without a permit is illegal and can result in fines or imprisonment. Check if you need a standard rules permit or a bespoke one.

  • Get an environmental permit for liquid waste discharges
  • Applies to trade effluent, sewage, and contaminated run-off
  • Discharging without a permit is a criminal offence
  • Fines can be unlimited, up to 5 years’ imprisonment
  • Use standard rules permit if your activity is lower risk
  • Apply for a bespoke permit if your discharge is complex
  • Check water body classification before applying
  • Monitor and report on Priority Substances in your discharge
  • Use the Catchment Data Explorer to check water status
  • Trade effluent to public sewers needs consent, not a permit
On this page
UK-wide

Related guides in Environmental Permits

If your business discharges liquid effluent, waste water, or contaminated run-off into rivers, streams, estuaries, the sea, or onto or into the ground, you need an environmental permit from the Environment Agency. This includes trade effluent discharged directly to the environment (not to a public sewer), sewage from private treatment plants, contaminated surface water, and cooling water.

Discharging without a permit is a criminal offence that can result in up to 5 years' imprisonment and an unlimited fine on indictment. The Environment Agency has a range of enforcement options including civil sanctions, enforcement undertakings, and prosecution.

Important distinction: If you discharge trade effluent into a public sewer, you need trade effluent consent from your water company, not an environmental permit from the Environment Agency. See the separate guide on trade effluent consent.

How the Water Framework Directive shapes your permit conditions

Every water discharge permit and groundwater activity permit must be decided in line with the Water Framework Directive. Two WFD mechanisms directly shape the conditions on your permit:

No-deterioration test

The Environment Agency or Natural Resources Wales must apply the no-deterioration test: your discharge must not cause any ecological or chemical status element of the receiving water body (or downstream water bodies) to drop a class. If it would, the permit is refused or conditioned with tighter emission limits. Check the current classification of the receiving water body on the Catchment Data Explorer (England) or Water Watch Wales before preparing your application — a water body already at Good status has little headroom.

Priority and Priority Hazardous Substances

The Environmental Quality Standards Directive sets a list of Priority Substances (including metals such as cadmium, nickel, lead, and mercury; persistent organic pollutants such as PAHs; and certain pesticides) with numeric Environmental Quality Standards. If your discharge contains any of these, your permit will set emission limit values aligned with the relevant EQS, plus monitoring and reporting obligations. A smaller group of Priority Hazardous Substances is subject to a cessation or phase-out obligation — you must demonstrate a substitution or elimination plan.

Practical preparation

  • Identify the receiving water body and its current classification before deciding on treatment technology.
  • Screen your effluent against the Priority Substances list (Annex 10 of the WFD as transposed) and EQSD Annex 1.
  • Commission a mixing zone assessment where numeric EQSs are likely to be tight.
  • Expect tighter conditions if the receiving water is a Drinking Water Protected Area, shellfish water, or bathing water.

Standard rules or bespoke permit

The Environment Agency offers two types of water discharge permit:

Standard rules permits

If your discharge is lower risk and fits within a published set of fixed conditions, you can apply for a standard rules permit. These are quicker (approximately 4 weeks) and cheaper to obtain. Standard rules permits are available for activities such as:

  • small sewage treatment plants discharging up to 5 cubic metres per day to surface water, or up to 2 cubic metres per day to ground
  • certain low-risk industrial discharges
  • vehicle wash water discharges that meet specified conditions

You cannot use a standard rules permit if your discharge is near a protected site (such as a Site of Special Scientific Interest) or if it does not meet every condition in the standard rules set.

Bespoke permits

If your discharge is more complex, higher risk, or does not fit standard rules, you need a bespoke permit. The Environment Agency will set tailored conditions based on a risk assessment of your specific discharge. Processing takes up to 4 months, and longer if public consultation is required. A habitats assessment surcharge applies if your site is near a protected habitat.

Groundwater protection

Discharges to groundwater (water below the surface in the saturation zone) are subject to additional controls. The regulations require the prevention of hazardous substances entering groundwater and the limitation of non-hazardous pollutants to prevent pollution.

How to apply

  1. 1

    1. Check whether you need a permit

    Use the GOV.UK guidance to confirm your discharge activity requires a permit. Some very small discharges may be exempt or excluded. If you discharge to a public sewer, you need trade effluent consent from your water company instead.

  2. 2

    2. Determine standard rules or bespoke

    Check whether your activity fits within a standard rules set. If it does, you can use the simpler and cheaper standard rules application. If not, you must apply for a bespoke permit.

  3. 3

    3. Consider pre-application advice

    The Environment Agency offers enhanced pre-application advice for a fee. This is recommended for bespoke applications to identify issues early and reduce the risk of your application being returned or refused.

  4. 4

    4. Prepare your application

    For standard rules, complete forms Part A and B4. For bespoke permits, complete Part A and B6 and include a site plan, drainage plan, risk assessment, and details of proposed monitoring. Include a discharge characterisation showing what substances are present.

  5. 5

    5. Submit your application and fee

    Send completed forms and payment to the Environment Agency Permitting and Support Centre. Check the tables of charges for current fees. Incomplete applications will be returned.

  6. 6

    6. Comply with permit conditions

    Your permit will specify discharge limits, monitoring requirements, and record-keeping obligations. You must submit monitoring data to the Environment Agency as required and pay annual subsistence charges.

Monitoring and compliance

Most permits require you to:

  • regularly sample and analyse your discharge for specified parameters (such as pH, suspended solids, BOD, ammonia, specific chemicals)
  • measure and record discharge volumes
  • maintain a monitoring log available for inspection
  • submit monitoring returns to the Environment Agency at specified intervals
  • notify the Environment Agency immediately of any permit breach or pollution incident

The Environment Agency inspects permitted sites and checks compliance with conditions. Non-compliance can result in enforcement action, including suspension or revocation of your permit.

Common discharge situations

Construction sites

Dewatering excavations, managing silt-laden runoff, and disposing of concrete washwater typically require a discharge permit. Plan for this early in your project timeline.

Small sewage discharges

If your premises is not connected to a public sewer and uses a private sewage treatment plant, you need a standard rules permit or an exemption for discharges of treated domestic sewage up to 5 cubic metres per day to surface water, or up to 2 cubic metres per day to ground.

Cooling water

Industrial cooling water returned to a watercourse at elevated temperature requires a bespoke permit. Thermal pollution can harm aquatic life, so the Environment Agency sets specific temperature limits.

What to do next

After obtaining your water discharge permit, consider whether you also need:

  • trade effluent consent from your water company if any of your discharges go to a public sewer
  • a water abstraction licence if you take water from natural sources before discharging it
  • a flood risk activity permit if your discharge outfall is on or near a main river or flood defence
  • to register your septic tank or treatment plant if it serves domestic premises

Official guidance on GOV.UK