Boots UK Ltd v Severn Trent Water Ltd

A liquid formed by mixing trade effluent with surface water before discharge into a public sewer falls within the statutory definition of “trade effluent” in Water Industry Act 1991, section 141(1). A sewerage undertaker may also use a charging scheme to deem the metered volume to be the relevant volume for charging purposes, even if the liquid includes material outside that definition. The scheme may lawfully provide limited machinery for replacing the metered volume where the meter is not accurately recording. A consent and charging scheme under the statutory regime do not ordinarily create a contractual relationship. Summary judgment is appropriate where the legal issue can be decided without disputed factual context, but limitation, discrimination and evidential issues may require trial.

Severn Trent applied for summary judgment against Boots concerning charges for liquid discharged from Boots’ manufacturing premises. Boots alleged that surface water had passed through its trade effluent meter, resulting in duplicate charging for surface water drainage and trade effluent. It brought restitutionary, unjust enrichment and contract claims, together with an undue discrimination claim, and challenged the limitation position and the evidential basis of claims before 1 October 1996.

The application required construction of section 141(1) of the Water Industry Act 1991 and Severn Trent’s charging schemes. The central questions were whether mixed liquid constituted trade effluent and whether the charging schemes deemed the metered volume to be the chargeable volume.

The application for summary judgment succeeded because issues 1 and 2 were decided in Severn Trent’s favour.

1. Statutory definition. The words “wholly or partly produced” in section 141(1) concern the composition of the liquid. A mixed liquid comprising trade effluent and surface water is partly produced in the course of trade or industry. The absence of an express exclusion for surface water did not require a different result. The legislative history, statutory purpose, context and consequences supported that construction. Yorkshire Dyeing and Proofing Co Ltd v Middleton Borough Council supported treating a mixture of trade effluent and water as trade effluent. The liquid was therefore trade effluent when mixed before discharge.
2. Charging scheme. Part D, paragraph 5(vi) of the 2005 scheme deemed the metered volume to be the relevant volume for charging purposes. The reference to “trade effluent” identified one possible metering data point; it did not require Severn Trent to separate or adjust the metered volume. Paragraph 5(vii) supplied the machinery for replacing the meter reading where Severn Trent ceased to be satisfied that the meter was accurately recording. Until then, the metered volume governed the charge.
3. Section 136. The deeming provision did not contract out of section 136. That section concerned the evidential presumption of meter accuracy, whereas the scheme lawfully selected a deemed volume for calculating charges under the wide powers in sections 142 and 143.
4. Alternative issues. The statutory consent and charging scheme did not create an actionable contract from 2005 onwards. The contract claims for 1996–2000 and from 26 August 2005 were suitable for summary judgment, subject to the identified contractual-counterparty issue. The claims based on undue discrimination, limitation and the pre-1996 evidential deficiencies were not fanciful and would not have been summarily determined.

First-instance decision. No appellate history was stated in the judgment.