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Trade effluent can damage our sewers, sewage treatment processes and the water courses that we discharge to. It can also affect the health and safety of anyone working in or around our sewerage network. We need to ensure that our infrastructure and treatment processes work effectively, so that your treated wastewater can be returned safely back into the environment.

What is Trade Effluent?

The Water Industry Act 1991 defines trade effluent as "any liquid, either with or without particles of matter in suspension in the liquid, which is wholly or partly produced in the course of any trade or industry carried on at a trade premises."

Anything that isn't domestic sewage (toilet, bath or hand wash waste) or uncontaminated surface water and roof drainage (rainwater) is classified as trade effluent. It’s essential that we're made fully aware of any trade effluent produced at commercial or business premises, so that we’re able to treat it safely. This includes any wastewater derived from a production process or from washing down or cooling activities.

Wastewater discharges from hotels, pubs, restaurants, takeaways and caravan parks are not classed as trade effluent. They are, however, regulated under Section 111 of the Water Industry Act 1991. Premises found to be discharging fats, oils, greases and food scraps into the sewer, which then cause blockages or compromise the safe operation of our assets, can be prosecuted.

Next steps to apply for a consent ...

IWNL operate as a wholesaler, so if you require a trade effluent consent within our licence area this must be obtained from IWNL, not the incumbent water company.

Please note that you will need to speak to your appointed Retailer if you have any questions about the application form, you will also need to submit the completed form through your Retailer. Please note that any forms without Retailer details will be returned.

All Trade Effluent applications or requests to change existing Trade Effluent discharges must be made using a standard document, depending on your circumstances this will either be a G/02 or G/03 form. Please see below for the difference between the two application forms, along with links to our application forms and guidance notes.

In addition to the completed G/02 or G/03 form, we also require a comprehensive plan of your site drainage system showing the route taken by the trade effluent discharge to the public sewer.

Once we've received your completed form, we will either grant or refuse consent within two months.

Form G/02 should be used when:

  • Applying for a new Trade Effluent consent (for discharges greater than 6 months duration).
  • Requesting a variation to an existing Trade Effluent consent.
  • Request for the discontinuation / re-activation of a Trade Effluent Consent.
  • Requesting that an existing consent be terminated.

A copy of our G/02 Form can be downloaded here.

For G/03 should be used when:

  • Temporary discharge <6 months.
  • If the discharge is greater than 6 months, a permanent consent must be applied for using a G/03 form. The discharge must be to a public foul sewer at a specified point.

A copy of our G/03 Form can be downloaded here.

A copy of our Guidance note can be downloaded here.

What this allows and what to notify us about...

The consent to discharge trade effluent will be issued in the name of your business, at the address of your trade premises, and only permits discharge of the effluent specified.

All of the conditions and limits stated in your consent to discharge are legally binding. Please make sure that you read your consent document carefully and store it in a safe place.

The consent contains various limits, trade effluent discharges containing any substance not previously declared on the Trade Effluent Notice are illegal.

You must therefore give us notice, in writing, of the following:

  • Any proposed changes to the nature or constituents of the trade effluent.
  • Any proposed changes to the rate of discharge or daily volume discharged.
  • A proposed change of ownership of the trade premises - consents are not transferrable from one company to another. If you sell the company, merge with another, or in any way change the legal status of the company, the new company must apply for a new consent.
  • Any proposed change to the name of the company or partnership.

Monitoring your flow to our network...

Trade Effluent consents normally requires equipment to be installed that will measure the flow. If you're discharging this effluent into the sewer system, you are responsible for installing and maintaining that equipment.

Our Trade Effluent records...

We are required to keep a register of trade effluent consents and associated documents, to which the public must be given access. The register is currently held at our offices in Cardiff, CF10 4BP.