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Industry leading
trade effluent services

Whatever the size of your business, we take the hassle out of trade effluent  

Expert trade
effluent team

Our expertise and market leading technology combine to make the process simple for you.

water audit

Consent and regulatory support

Full-service support for correct consents and licenses and the application process.



Consistently reliable, hassle-free bills from our market-leading billing platform.


Data to support sustainability targets

Support and data reporting to help sustainability and environmental targets.

Getting trade effluent right is crucial

Trade effluent consent is a vital part of wider legislation which protects the environment. It’s illegal to discharge trade effluent without consent and doing so carries the risk of prosecution and fines. 

If you think you're being overcharged for your business water, or under-served in your trade effluent needs email or call 01250 718718 to speak to one of our experts.

Put a heavyweight in your corner

When it comes to high volumes of water, wastewater and trade effluent, you need a team on your side that can cut through the noise, provide no-nonsense expert advice and guidance, and fight in your corner through any supply disruptions or Wholesaler disputes.

Trade effluent requirements can be complex and confusing, and businesses can quickly find themselves in hot water. Discharging trade effluent without consent is illegal and may lead to prosecution and fines. 

Castle Water has the resource and expertise you need, and we make the process simple for you. Email or call 01250 718718 to speak to one of our experts.

You can trust our experts

Unlike other retailers, we have a dedicated trade effluent team ready to support you. We have the experience and technology required to understand trade effluent like no one else – and we make the process simple for your business.

Email or call 01250 718718 to speak to one of our experts.

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Consents and negotiation

Typically, larger industrial customers must negotiate with their wastewater Wholesaler to arrange bespoke consent limits. We have the knowledge and influence to ensure that your interests are properly considered. We’ll advise you on these discussions, help to negotiate consent applications, and support you to challenge Wholesalers on a range of issues.

Consistenly reliable bills

Our market-leading billing platform produces consistently reliable invoices with the highest degree of accuracy, and our customer portal makes it easy to submit monthly meter readings online, so your bills stay up-to-date and reflect actual consumption. Log in to see view letters and bills, produce statements, search transactions, and check usage. You can also go paperless for fast, reliable and eco-friendly.

Suez Logo

SUEZ Switch Over 200 Sites To Castle Water For Optimised Services And Solutions

Optimum services and solutions

The objective: To consolidate their portfolio with one retailer that can provide optimum services and solutions, and fix billing problems caused by previous market errors. 

Castle Water prioritised a data cleanse of SUEZ’s entire portfolio to rectify the inherited market errors and ensure accurate billing. To cater to SUEZ’s multi-site needs, Castle Water implemented its consolidated billing solution to simplify billing and improve cost management. 

The result: SUEZ now has confidence in its water, wastewater, and trade effluent charges.

Julie Swanepoel, Procurement Officer at SUEZ, said: “Castle Water continue to provide exceptional service and support. Consolidating all our sites with Castle Water has generated real efficiencies and cost savings, and they deliver vital support in the management of our business water across the UK. Their additional water services and water efficiency measures offer added value and environmental benefits and highlight our aligned sustainability values.”

Email or call 01250 718718 to speak to one of our experts

Castle Water raises more Trading Disputes than any other retailer

We're the only retailer taking all possible steps to resolve customer problems resulting from wholesaler data errors, and no other retailer is doing so.

Unlike other retailers, Castle Water has the expertise and resource required to raise and go through the process for a Trading Dispute.

Businesses producing significant amounts of trade effluent must consider their water retailer’s ability to provide as much expertise and support as possible.

Trade effluent for industrial and multi-site customers

What is trade effluent

Trade effluent is any liquid waste (effluent) discharged into the sewers from a business or industrial process. This includes any wastewater produced from washing or cooling activities, as well as process production waste determined to be appropriate for disposal via the sewer network.

Trade effluent does not include waste that is classed as regular sewerage – waste water from kitchens, bathrooms and toilets; therefore, most hotels, restaurants, cafes, pubs, and hairdressers would not require a trade effluent consent.

Typical business types that do require a consent include car washes, launderettes and dry cleaners, transport depots, breweries, dairies and commercial swimming pools. Trade effluent and Greywater recycling customers can be large or small businesses.

A trade effluent consent does not permit discharge of potentially hazardous chemicals to the sewer – businesses must ensure waste of this nature is disposed of responsibly via a specialist waste contractor.

The links below provide the forms and guidance notes to complete an application for consent. Forms can be completed and sent by email to

Apply for trade effluent consent:

If your business needs trade effluent consent, the easiest way to apply is by logging in to the customer portal.  

Apply for trade effluent via downloadable form

Glossary of Terms

Frequently asked questions

Unlike domestic sewerage, trade effluent is highly variable in terms of volume and contamination strength. It is therefore necessary to regulate this wastewater to ensure the sewerage network can adequately handle and treat the waste. This is to protect the health and safety of staff and to protect the environment.

To regulate trade effluent, businesses are provided with a licence, or discharge consent. The licence defines the nature of the allowable discharge and establishes any restrictions. Samples of the trade effluent discharge are taken regularly to ensure the customer is complying with the terms of their consent.

It is a criminal offence to discharge trade effluent waste without a consent.

Unlike sewerage, trade effluent charges relate to the contamination strength. Further information on these rates can be found in our Scheme of Charges. Many customers will find their trade effluent rate to be lower than their sewerage rate.

In addition, there are fixed fees for consent applications, and any additional waste sampling requested by the customer.

Explanation of the trade effluent rate

The volumetric rate (£ / m3) is calculated according to the Mogden formula. This says that the overall charge is the sum of rate components corresponding to different parts of the effluent treatment process. These are:

Primary treatment and reception and convoy are independent of the amount of contamination, and the other charges are proportional to the concentration of contaminants. Trade effluent goes through the same treatment processes as sewerage, and subsequently the sewerage rate includes these same charge components, but on a non-variable basis.

Yes. Short term consents can be issued for activities such as construction; charges for effluent discharge will be issued in advance.

Most waste volumes are determined from the metered potable water. Allowances may be subtracted to account for water not returning to the sewer, as well as allowing for sewerage waste.

Some customers may choose to install a waste meter to measure the volume directly. Without metered volumes the wholesaler will provide an estimated annual volume based on the business activities.

If regular meter readings are not being submitted, customers may be billed on a scheduled basis.

Invoicing will be based on estimates determined by the last actual meter readings.

Submitting regular meter readings allows us to invoice more accurately. Trade effluent invoices are issued in arrears, so we require regular meter readings for all meters to invoice on a read-to-read basis. Meter readings can be submitted to

Tariffs are split into several different ‘bands’ corresponding to the annual chargeable volume that the tariff applies to. The wholesaler determines which tariff applies for each water services component.

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