Appeal against Severn Trent Water Limited about a variation of a trade effluent consent


Case number


Case summary

This appeal was about a proposed variation by Severn Trent Water to an existing trade effluent consent it had in place with a commercial user. A variation to a trade effluent consent is essentially where a company varies the terms and conditions associated with an existing trade effluent consent.

In this case Severn Trent Water sought to vary a particular condition in an existing consent relating to the pH level the discharges from the Complainant’s site must have. This change was to bring the consent into line with the standard policy Severn Trent Water currently applies in relation to the pH levels of discharges in the consents it issues. The proposed variation Severn Trent Water wished to make would have tightened the requirements in the consent, raising the minimum pH level all discharges must achieve.

Summary of Ofwat’s final decision

Following our investigation of the complainant’s appeal, we determined that in light of the legal framework of the Act and the evidence we gathered from the parties to the dispute, that Severn Trent Water’s proposed variation to the trade effluent consent between itself and the Complainant was not appropriate and should not stand. This was in large part because Severn Trent Water could not evidence site-specific reasons for requiring the change to this long-standing consent, for example to demonstrate that the existing conditions were causing harm, and because the proposed variation would likely have material financial impacts for the Complainant. Therefore, the previous consent held by the Complainant remains in place.

Wider lessons for companies and customers

In accordance with section 126 of the Water Industry Act 1991 (the Act), owners or occupiers of any trade premises may appeal to Ofwat against a direction which varies trade effluent consent conditions, but only where it is within two months of receiving the notice of the direction to vary the consent’s conditions or, if at a later time, with Ofwat’s written permission.

On receipt of an appeal, we have the power to annul the direction given by the sewerage company and substitute it for any other direction, whether more or less favourable to the appellant.

In this case Severn Trent Water sought to vary a specific condition within a long-standing trade effluent consent, primarily in order to bring the condition into line with Severn Trent Water’s current standard policy. Severn Trent Water sought to justify this in general terms, explaining the rationale behind its wider policy and its view that this policy approach enables it to process and monitor trade effluent consents more easily.

Severn Trent Water was not, however, able to evidence that its concerns regarding pH levels in discharges in general were relevant or indeed harmful in the specific circumstances of Complainant’s site, in particular given the significant period of time the existing consent condition had been in place and recently monitoring activities undertaken. Changing the consent’s condition would likely entail a material expense for the Complainant to then be able to comply with the tighter requirement. Our determination found that it was not appropriate for Severn Trent Water to apply its general policy approach in this specific case, and that it should have taken greater account of the specific and actual circumstances of the site to establish whether a change was justified.

Relevant powers

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

Relevant Ofwat guidance

Ofwat – Trade Effluent Appeal Guidance

Relevant documents

Final determination – Appeal against Severn Trent Water Limited about a variation of a trade effluent consent

Date opened

9 June 2022

Date closed

10 August 2023


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