Network Rail Infrastructure Ltd v Williams [2018] EWCA Civ 1514

  • Court of Appeal clarifies that, where Japanese knotweed is encroaching on their land, landowners do not have to wait until physical damage to their properties occurs before bringing an actionable claim in private nuisance.
  • The judgment brings clarity to the law of private nuisance; the implications extend far beyond Japanese knotweed to other forms of nuisance, such as other forms of invasive plant, dust, fumes and noise.


Over the past few years there has been increasing awareness about the threat posed by Japanese knotweed and new measures have been introduced to combat its spread.

The Anti-social Behaviour Crime and Policy Act 2014 grants local authorities and the police the power to issue community protection notices which require a person to control or prevent the growth of Japanese knotweed (or other plants capable of causing harm to communities). Under the Infrastructure Act 2015, the Secretary of State, the Environment Agency, Natural England, and the Forestry Commissioners have powers to issue species control agreements and species control orders against invasive non-native species of plants or animals, including Japanese knotweed. It is a criminal offence to fail to comply with a community protection notice or a species control order.

Network Rail

The judgment in Network Rail is concerned with action taken by private individuals (the respondents) faced with Japanese knotweed encroaching on their land. Their claim in private nuisance had been successful in the County Court. Network Rail appealed to the Court of Appeal.

Sir Terence Egerton, Master of the Rolls, gave the judgment on behalf of the Court.

Before recording the facts of the case, Sir Terence Egerton MR considered the nature of Japanese knotweed. He said that it is a strong and fast-growing bamboo-like perennial plant that spreads through its roots or underground stems called rhizomes. He observed that, once established, it can be difficult to eradicate and noted the advice given by the Environment Agency that knotweed should be burnt, a non-persistent herbicide applied, and the site soil and the burnt remains then buried in particular way under expert supervision. Finally, he stated that the presence of Japanese knotweed in the vicinity of a property can be sufficient to affect the property’s value.

The respondents’ adjoining properties abutted an access path (bordered by a post and wire fence) and an embankment that were owned by Network Rail. On the embankment there was a large stand of Japanese knotweed, which the parties accepted had been there for at least 50 years.

In the County Court, the recorder had accepted that the Japanese knotweed had encroached onto the respondents’ land, but refused the respondents’ claim in private nuisance on this ground as there had been no physical damage to their properties. However, he held that Network Rail had failed in its obligation as a reasonable landowner to eliminate and prevent interference with the quiet enjoyment of the respondents’ of their properties. He further held that the continuing presence of the knotweed and the reduction in value to the respondents’ properties represented a continuing nuisance, and awarded damages.

Sir Terence Egerton MR considered the present principles of the tort of nuisance:

  • First, private nuisance is a violation of real property rights (i.e. interference with the legal rights of the owner of land or interference with the amenity of the land);
  • Secondly, although nuisance is often broken down into categories (encroachment, interference and physical injury), these are simply examples of a violation of property rights;
  • Thirdly, physical damage is not necessary for an interference to be actionable as damages may be awarded for the loss of the land’s intangible amenity value;
  • Fourthly, nuisance may be caused by inaction or omission as well as by some positive activity. An occupier would be liable if they failed to use reasonable means to bring a nuisance to an end where there is actual or presumed knowledge of it and ample time to do so. They would also be liable if they if they failed to take reasonable action to remove a hazard on their land of which they were aware and where there was a foreseeable risk that it would damage a neighbour’s land and did go on to damage it.
  • Fifthly, the broad unifying principle in respect of the law on nuisance is reasonableness between neighbours (whether real or figurative).

In considering the judgment of the recorder in the county court, Sir Terence Egerton MR said that the purpose of the tort of nuisance was not to protect the value of property as an investment or a financial asset, but to protect the landowner (or a person entitled to exclusive possession) in their use and enjoyment of the land. He further stated that the judgment of the recorder extends the tort of nuisance to a claim for pure economic loss; this was not an incremental development of the law, as the recorder had suggested, but a radical reformulation of the purpose and scope of the tort.

Turning to consider the respondents’ main grounds of appeal, Sir Terence Egerton MR said that he did not agree with the recorder’s analysis and decision in relation to the encroachment of the rhizomes of the Japanese knotweed onto the respondents’ land. He stated that the presence of Japanese knotwood, indeed the mere presence of its rhizomes, imposes an immediate burden on a land owner in that it makes it more difficult and more expensive for the landowner to develop the land, should they wish to do so. The knotweed and its rhizomes, he said, represent a “natural hazard”, they affect the landowner’s ability fully to use and enjoy their land, and they interfere with its amenity value.

Sir Terence Egerton MR concluded that the findings of fact made by the recorder concerning Network Rail’s knowledge of the presence knotweed on its land and its failure reasonably to prevent the interference with the respondents’ enjoyment of their properties were sufficient to give rise to a cause of action in nuisance.

As to the appropriate remedy, he stated that he could see no reason why a claimant should not be able to obtain a final mandatory injunction in appropriate circumstances, such as those in the case before him, where the amenity value of the land is diminished by the presence of roots, even though there is yet to be any physical damage.

Finally, Sir Terence Egerton MR refused Network Rail’s “rather obscure” ground of appeal that the issue of damages should be remitted to establish whether or not its expert would adjust his view of the market value of the respondents’ properties having regard to the full extent of the Japanese knotweed that had existed for many years. He said that it was for Network Rail to ensure that its expert was properly instructed and that the cost of remitting the issue would be disproportionate to the amount of damages involved.

Practical points

This case will greatly encourage landowners concerned about the growth of Japanese knotweed near their land. Those with Japanese knotweed growing on their land should seek professional advice on how to eradicate it if there is any risk of a future claim by a neighbouring landowner

However, the implications of this judgment extend far beyond Japanese knotweed. It is now clear that any interference (e.g. by an invasive plant, dust, fumes or noise) can give rise to an actionable claim, even if it is yet to cause physical damage to a landowner’s property, as long as the amenity value of the land has been diminished.

The clarity that this case provides will not only make it easier for claimants to bring claims, but it also will make it easier for complaints to be resolved at a pre-action stage.