Bell & Anor v Northumbrian Water Ltd

A statutory sewerage undertaker may owe a common-law duty in nuisance where the complaint concerns operational failures, such as inadequate maintenance or repair, rather than strategic decisions falling within the statutory regulatory scheme. Any nuisance must be fault-based. The use of independent contractors does not by itself relieve the undertaker from responsibility for an existing nuisance which it has failed to abate. In a claim concerning subsidence, the claimant must establish causation on the balance of probabilities. The court applied the ordinary but for test and held that the alleged leakage had not caused or materially contributed to the slope instability.

The claimants owned and occupied a property beside a steep, unstable bank descending to Ogle Letch. A sewer owned and operated by the defendant ran near the property and had suffered defects and leakage. The claimants alleged that sewage or subsurface water had travelled through the sewer or its trench, saturated the bank and caused landslip which removed support from their land.

The defendant relied on limitation, the statutory enforcement scheme under the Water Industry Act 1991, absence of fault, independent contractors and lack of causation. The hearing was confined to liability and causation. The central issues were whether the claim was justiciable in nuisance and whether the sewer or trench had caused or materially contributed to the instability.

1. Justiciability and statutory scheme. The principle in Marcic v Thames Water Utilities Ltd did not prevent a nuisance claim concerning an operational failure to maintain or repair sewerage infrastructure. Following Dobson v Thames Utilities Ltd, the distinction between operational matters and strategic matters was one of fact and degree. Failure to maintain or adequately repair the pipe was operational and capable of founding a claim. A major diversion project might be strategic, but the issue did not affect the result.
2. Nature of liability. The claim had to be fault-based. The defendant could not avoid responsibility merely because contractors had been used. The alleged nuisance was said to have existed independently of the contractors, who had at most failed to abate it. The continuing nuisance principle in Sedleigh Denfield v O’Callaghan supported that conclusion. The intervening fact that the directly affected bank was not owned by the claimants did not, on the submissions before the court, prevent a claim for withdrawal of support.
3. Causation. The court preferred Dr Jones’s evidence to that of Dr Reeves. The evidence established substantial alternative sources of water, including drainage channels, highway drainage, surface water, a high water table and rainfall. The court rejected the alleged permeable trench pathway as insufficiently established and found that any leakage from the sewer was negligible by comparison. Even if material contribution were the applicable test, it had not been proved. Applying the approach in Chetwynd v Tunmore, the claimants had not shown that, but for the defective pipe, trench or fluid, the instability would not have occurred.
4. Disposition. Causation was not established and the claim therefore failed. The judge added, obiter, that he would probably have found no fault: the defendant had reacted timeously to complaints and reasonably instructed competent contractors.