Original case - Williams v Network Rail
In May 2017 we advised on the outcome of this case in which the County Court ruled that the presence of Japanese knotweed on an adjoining property to the claimants' properties was an actionable nuisance and in which the recorder ordered payment of remediation costs plus compensation for any residual fall in the properties' value because of lender caution.
The Court of Appeal on 3 July 2018 upheld the County Court decision but on different grounds. Sir Terence Etherton, the Master of the Rolls, said that the County Court decision was wrong as you cannot extend the nuisance of tort to a claim for pure economic loss (in tort you can only claim for physical not economic loss). However, he said that Japanese knotweed and its underground roots are a natural hazard and can affect a property owner's ability to fully use and enjoy the land and therefore found that the encroachment of Japanese knotweed onto the claimants' land was "a classic example of interference with the amenity of land" and upheld the County Court decision for that reason.
What is the significance of this decision?
Japanese knotweed continues to be a deep rooted problem both on your property and on adjoining property.
If it is on your property you should make every effort to treat it as it can affect the marketability and fundability of your property (many banks won't lend if it is present). If you fail to disclose on sale a purchaser could have a claim in damages or even in extreme circumstances rescind the contract due to reliance upon a misrepresentation.
If it encroaches onto adjoining land you could face a claim for nuisance or even an injunction to treat as was awarded in the case of Smith v Line where experts found that Japanese knotweed had encroached from Line's land to Smith's land and the judge granted a mandatory junction requiring Ms Line to enter into a contract with a reputable contractor to treat the Japanese knotweed on her land and ordered her to pay the claimant's costs.
If you are purchasing a property it is imperative that you or your surveyor carry out a careful inspection of the Property as there is no dataset available for the presence of invasive plants.