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.

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.

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

Application Guidance Notes

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

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