Trade Effluent

If you want to learn more about trade effluent and how you can apply for trade effluent consent, you've come to the right place.


Yorkshire Water can help your business monitor and manage your impact on the environment.

In this section, we're focusing on trade effluent, what it is and what it means to your business. If you want to learn more about trade effluent and how you can apply for trade effluent consent, you've come to the right place.

Find out below how our trade effluent services can help you.

What is trade effluent?

Trade effluent is the liquid waste from a business or industrial process that passes to public sewer.

The liquid waste from various industries and processes is classed as trade effluent and includes liquid waste from car washes, laundrettes, metal finishing, textiles through to large chemical works, food and beverage manufacture etc.

Control of trade effluents applies to companies of all sizes and consents may be required for discharges of only a few litres per day and also to discharges that are made infrequently.

The definition of a trade effluent does not include toilets, sinks, personal cooking, and uncontaminated surface water drainage.

Wastewater discharges from hotels, pubs, restaurants, takeaways and caravan parks are not currently classed as trade effluent. However premises found to be discharging materials such as fats, oils, greases and food waste to sewer that cause blockages or affect the  operation of water company assets, can be controlled under another part of the Water Industry Act.

Read our code practice document


What is a trade effluent consent and why do I need one?

A trade effluent consent is a legal document that sits with the property and is required if you wish to discharge trade effluent to the public sewer. It is in effect a licence giving permission to discharge to public sewer.

It contains however a number of conditions related to the volume, flow rate and nature of the effluent that are set to protect the environment and water company assets – the sewerage network, the sewage treatment processes and personnel (employees and general public), for example. Differing conditions and range of substances to be controlled may be set taking into account the industry type of the effluent and the receiving sewer and sewage treatment works.

There may also be conditions that require the discharger  to provide apparatus  that will measure and record trade effluent flows, pH and temperature etc. An automatic sampling machine may also be necessary.

Short term discharges such as contaminated groundwater from building projects or ground remediation, flushing of heating or cooling systems in commercial properties, etc. would be  subject to temporary trade effluent consent arrangements.

We need to know if you plan to discharge anything other than domestic waste into the public sewer. It is your responsibility to obtain consent prior to commencing any trade effluent discharge.

As consents are attached to a premise, they can be transferred to a new occupier, provided that the type of business is unchanged and the trade effluent discharge remains the same.

It is important to tell us immediately if you no longer require a trade effluent consent. Charges will only be cancelled from the date you sign and return a termination request to us. This is because we will continue to reserve capacity for your business, regardless of whether you are discharging effluent.


Applying for a trade effluent consent

If you are planning to discharge trade effluent to public sewer or you have an existing discharge that you think requires a consent please contact your appointed retailer to discuss further. They can offer advice on applying for a Consent or making a change to your existing Consent and may apply on your behalf. 

If you do not know who your retailer is you can look on your previous water bill for this information or check the Open Water website.
From April 2017 all Trade Effluent applications or requests to change existing Trade Effluent discharges must be made using a national standard document, known as G/02 Form. Your appointed retailer should be able to assist you with this.

We require details of the process giving rise to the trade effluent discharge, your water usage and estimates of daily trade effluent volumes. In addition to completing the G/02 form you will also be required to provide a clear and comprehensive plan of the site drainage system showing the route taken by the trade effluent to the public sewer.

See an example plan

A designated sample point also needs to be identified and marked on the plan, where samples of the trade effluent can be obtained this is a legal requirement of a consent.

This point should be downstream of any treatment the trade effluent may receive but before it mixes with any other site drainage such as surface water or domestic effluent. The sample point should afford easy and safe access for sampling at all times.

There are charges associated with the application for, and subsequent issue of, a trade effluent consent and these are shown in our current charges scheme booklet.

It may not be possible, unfortunately, to meet with your requirements and consent may be refused. The reason that a Consent cannot be granted or changed will be discussed with you and or your Retailer and possible alternatives may be offered. Reasons for refusal may include lack of treatment capacity at the receiving sewage works, for instance.


Trade effluent charges

From April 2017 your trade effluent bill has been calculated based on information provided by Yorkshire Water Services (wholesaler) and your retailer to an independent market service provider, this is currently Market Operator Services Limited (MOSL).

Your billing services is being provided by your retailer and not by Yorkshire Water.

Find more information about MOSL

The trade effluent charge is calculated taking into account the strength and volume of the trade effluent discharge. Not all trade effluents are therefore charged at the same rate although we do have regional charging strengths for vehicle washes and launderettes.

Generally a range of samples are taken and the average strength of these samples is used to calculate a unit charge for trade effluent i.e. a price per cubic metre of trade effluent.  A formula known as the Mogden Formula is used to calculate this.

The formula comprises of four parts and they relate to charges for:
- the carriage of the trade effluent to the sewage treatment works via the public sewer
- preliminary treatment of sewage at the waste water treatment works (screening & grit removal)
- biological treatment of the sewage
- sewage sludge disposal & treatment

Yorkshire Water Services also charges separately for other trade effluent activities and this is detailed in our current trade effluent charges scheme booklet.

There is a minimum charge applicable to trade effluent accounts and this is detailed in our current wholesale charges scheme booklet.

Retailer guide on trade effluent charges

Trade Effluent Meter & Sampling Equipment Policy


Consent compliance

The trade effluent consent is a legal document and compliance with the conditions is a legal requirement, under criminal law.

You will be provided  with analysis reports for every sample taken from your premises so you will be able to keep a record of consent compliance. Reports that show consent failures will generally be accompanied by a letter and your trade effluent adviser will be available to discuss the matter in more detail should it be required.

We have a trade effluent enforcement policy that details our approach to non-conformance. We aim for a firm but fair approach that offers proportionality and consistency (but not absolute uniformity as a number of factors need to be considered before any decision can be made).

Factors to be considered include past performance, significance and impact of failure etc.

Read our enforcement policy.


Temporary and regional multi-site trade effluent consents

Yorkshire Water has now introduced, in addition to the existing temporary consent documents (for periods of up to six months), a Regional multi-site consent agreement. This is for replicated activities throughout the Yorkshire Water region carried out by a single contractor at different third-party sites. An example of where this would be used would be for water system flushes. Currently companies who carry out this activity need to apply via a retailer for each job they carry out.

The introduction of the Regional multi-site consent will mean that the contractor needs to make just one application via their chosen retailer for all the work they plan to carry out. This would be via a G03 form (SWIMPOOL process G2B.R) with the multi-site option chosen. Although the G03 is for agreements of up to six months the Regional multi-site agreement that is issued will not be time limited. There will be one temporary agreement fee for the multi-site agreement.

Once an agreement is held the contractor will be obliged, under the terms of the agreement, to inform Yorkshire Water at least 10 working days prior to the work going ahead. This will allow YW to assess the suitability of the discharge into the sewerage network and sewage works in which the premises are located.

Contractors will need to complete a form associated with the agreement and submit it directly to the YW Trade Effluent team using this email address.


Work cannot proceed until the relevant permission has been granted by YW, and like any application, permission is not guaranteed for an individual site.

This process has been introduced to help contractors and retailers gain permissions in a straightforward way and reduce unnecessary contacts between contractors, retailers and wholesalers.


Trade effluent public register

Members of the public can make an appointment to view the public register of trade effluent consents at our head office site in Bradford. Please contact us by email on to arrange an appointment.

Policy Documents

Code of practice

You can view this document in your browser or download it.

Enforcement policy

You can view this document in your browser or download it.

Trade effluent meter and sampling equipment policy

You can view this document in your browser or download it.

Retailer guide

You can view this document in your browser or download it.

Disposing of your liquid waste with us

You can dispose of your effluents with us to make sure you're getting a great rate, accurate charging and legal compliance.