A lot of the law on flooding has been developed by the courts. This is known as common law. At first, the courts felt that flooding was a natural event and that no one could be blamed for it.
Historically, flooding was regarded as a common enemy and everyone had the right to defend their property from flooding, even if their actions affected someone else's property (by causing their neighbours to be flooded instead, for example). The courts have now placed a greater duty of care upon landowners to use their land in such a way that it would not cause flooding to another’s property.
Under tort law, the branch of common law which deals with civil wrongs, you are entitled to legal remedy where a wrongful act has caused physical injury and damage to property. Most flooding cases fall under the tort of nuisance. Nuisance law deals with unlawful interference with a person’s use or enjoyment of land, or of some right over land or in connection with it. Before a flooding claim can succeed under nuisance law, the court will normally consider the following:
- Was the land used reasonably (sensibly)?
- Was there a clear likely risk that the use of the land would cause actual damage and harm to others?
- What steps did the party at fault take to prevent or reduce any damage?
Certain types of flooding such as sewage flooding would ordinarily be actionable under the common law of nuisance. However, a claim against a sewage undertaker will only succeed if it is brought under a statutory scheme provided by Parliament (see section on statutory law). An example is the scheme provided by the Water Resource Act 1991. See the case Marcic v Thames Water Utilities Ltd.
The remedies available under nuisance law are:
- Award of damages (financial compensation)
- Injunctions (an order to stop the nuisance from continuing)
Some important cases
Gerrard v Crowe  All ER Rep 266: judgment deals with the right of a person who owns land by a watercourse (a 'riparian owner') to take reasonable flood defence action.
Leakey v National Trust  1 All ER 17: establishes a general duty on occupiers of land where there are natural hazards to do all that is reasonable to prevent or minimise the risk of foreseeable damage to other people's property.
Home Brewery v Davis  1 All ER 637: judgment deals with the right of a landowner to drain surface water naturally onto lower land.