Problems with public water supply therefore generally are dealt with in the framework of the Water Industry Act 1991 and regulations).
Overall standards are mostly governed by European legislation incorporated in UK legislation. Bottled water is covered by European legislation also, though it is not always understood that standards are higher for tap water than for bottled water.
When water mains blow up, again, water undertakers are statutorily responsible for damage occurring without proof of negligence. Establishing legal liability for poisoning through water supply has been much more difficult, as witnesses in civil proceedings from Camelford and Northern Ireland. People who are hypersensitive to water quality issues may have difficulty in pursuing claims.
Private water supplies, however, mostly concern common law; there have been plenty of decided cases. Local authorities have statutory duties of testing, and there are significant penalties when pollution of private supplies is caused. In addition, the water undertaker can be called in by the local authority when supplies fail, and the local authority can also serve notices in relation to private water supplies to remedy problems.