Appeal against Southern Water about its refusal to issue a trade effluent consent


Case number


Summary of case

This appeal was about Southern Water Services Limited’s (“Southern Water”) refusal of a trade effluent consent application. The application was made by a business customer to enable it to discharge trade effluent from its trade premises into a public sewer. A trade effluent consent enables a water and sewerage company to set the terms and conditions by which a third party can dispose of its trade effluent into the company’s sewers.

Southern Water had refused the application for consent. This was because the relevant wastewater treatment works did not have sufficient headroom within the limits of the current environmental permit for the works, to receive the additional flows from the business customer. Southern Water had already started the process of applying to the Environment Agency for a permit variation to increase the limits within its environmental permit.

Following our consideration of the appeal, we issued a draft decision to the parties to the dispute. Our draft decision proposed to uphold Southern Water’s refusal of the trade effluent consent, given the ongoing process to vary the wastewater treatment works’ environmental permit and since the works was unable to accept additional flows for treatment until this process had completed. However, we made it clear that we expected Southern Water to:

  1. do all it could to facilitate the Environment Agency’s consideration of the variation to the permit at the earliest possible opportunity; and
  2. continue to engage meaningfully and proactively with the business customer to find a workable solution in the interim, particularly in light of Southern Water’s general duty under section 94 of the Water Industry Act 1991 to provide a sewerage system, including having regard to their existing and likely future obligations to allow for the discharge of trade effluent into public sewers.


Following the issuing of our draft decision, Southern Water and the Appellant re-entered discussions.

Southern Water has agreed to grant a trade effluent consent to the customer by a set date (driven by the customer’s business needs). This is dependent on Southern Water’s environmental permit variation application having been resolved by that date. If the variation has not been resolved by the required date, and therefore Southern Water remains unable to grant a trade effluent consent to the customer, it has agreed to tanker the customer’s trade effluent to another treatment works in the interim. In doing this Southern Water will ensure that the business customer incurs no additional cost in trade effluent charges than the customer would have otherwise faced. Based on the above, the customer decided to withdraw its trade effluent appeal.

Update – August 2022

Southern Water has confirmed that it has issued a trade effluent consent to the Appellant. Rather than tanker the Appellant’s trade effluent, as originally planned and set out above, it will now instead tanker the equivalent volume from elsewhere in the relevant catchment area, to an alternative wastewater treatment works. This will ensure that the wastewater treatment works mentioned above – which does not have sufficient headroom within the limits of its current environmental permit – does not receive any additional flows above those it already receives.

Wider lessons for companies

This appeal has highlighted important issues for all water and sewerage companies to be aware of when considering requests for trade effluent consents. In particular, companies should:

  • be aware of and meet their duty under section 94 of the Water Industry Act 1991 with respect to providing a sewerage network, including having regard to their existing and likely future obligations to allow for the discharge of trade effluent into public sewers, and to the need to provide for the disposal of trade effluent in accordance with section 94(1) and (2) of the Act;
  • engage with trade effluent customers, promptly and in a constructive manner to understand their current and potential future needs;
  • proactively consider and plan to ensure their assets and environmental permits are fit for purpose, including addressing, in a timely way, any potential issues that might prevent them from granting future trade effluent consents; and
  • take reasonable steps to understand and plan for future demands on their sewerage networks through engagement with relevant stakeholders.

Relevant powers

The relevant sections of the Water Industry Act 1991 associated with trade effluent

Relevant Ofwat guidance

Ofwat – Trade Effluent Appeal Guidance

Appeal received

23 October 2020

Appeal opened

15 April 2021

Appeal closed

13 April 2022

Closure page updated

1 August 2022