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 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 TEConsents@castlewater.co.uk.

Trade Effluent Discharge Application

For premises in England

For premises in Scotland

Application Guidance Notes

For premises in England

For premises in Scotland

Trade effluent experts

Trade effluent requirements can be complex. Castle Water’s dedicated, expert trade effluent services team has the experience and technology required to understand it like no one else – and we make the effluent treatment process simple.

Why are consents required for trade effluent?

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.

Accurate billing

Castle Water is recognised as a market leader in trade effluent billing. Our unique, state-of-the-art trade effluent invoicing system produces billing with the highest degree of accuracy.

Multi-site/large water users

If you are a large water user or you have multiple business sites, you may be producing a significant amount of trade effluent. We can help you to manage this.

Our specialised account managers can provide you with a wide range of support in legislation and charges to processes and requirements.

What charges apply to trade effluent customers?

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
  • Reception and Convoy
  • Biological Treatment
  • Solids Treatment
  • Ammonia Treatment

Primary treatment and reception and convoy are independent of the amount of contamination, and the other charges are proportional to the concentration of contaminents. 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.

FAQs and Glossary

Further information on trade effluent can be found in our FAQs & Glossary

Why am I sent new trade effluent invoices each month, for prior months?

Many customers want to know that their charges are auditable and can be traced back to these Wholesale charges. Unfortunately, if the Wholesaler enters sampling data in the Central Market Operating System after the month in which it is due to be recorded, this gives rise to a change in charges.

I think my business should have a Trade Effluent consent, what steps should I take?

Trade Effluent is any liquid waste discharged into the sewers from a business or industrial process. Trade Effluent is regulated to ensure the sewerage network can adequately handle and treat the waste.

To regulate Trade Effluent, businesses are provided with a license or discharge consent. Samples of the trade effluent discharge are taken regularly to ensure customers are complying with the terms of their consent.  The types of businesses that normally require consent include car washes, launderettes, and dry cleaners, transport depots, breweries, dairies, and commercial swimming pools.

What is Trade Effluent?

The best way to describe trade effluent is to begin with the definition of domestic effluent.

Domestic wastewater is anything disposed of in the sewerage system from toilets, sinks, washing machines and dishwashers. Anything that is not classified as domestic waste, or that is discharged in large volumes or is contaminated.

What is a SPID?

Every business premises has a unique Supply Point Identifier to identify the water and/or sewerage supplies at the property. The Supply Point Identifier number is also known as a SPID number.

Your SPID number is very important as part of your business water charges. It encompasses all of the chargeable data items related to your business premises including full meter details and return to sewer allowance.

Consent and compliance

Trade effluent consent is a vital part of wider legislation which protects the environment. Castle Water will support you with any compliance challenges to help you meet regulatory obligations, minimise environmental impact and reduce the risk of unexpected costs.

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. As well as advising you on these discussions, we help to negotiate consent applications – and challenge wholesalers – on a range of issues.