Japanese Knotweed: Not just a weed – but a legally actionable nuisance

On Tuesday 3 July 2018 the Court of Appeal upheld a Welsh County Court decision that individuals whose property had been encroached upon by ‘pernicious’ Japanese knotweed were entitled to financial compensation.

In this instance the neighbour at fault was Network Rail whose failure to deal with Japanese Knotweed originating on land behind properties owned by Mr Williams and Mr Waistell resulted in the plant spreading into the gardens of the two adjacent bungalows.

The bungalow owners had first alerted Network Rail to the encroachment in 2013. Japanese knotweed, which grows quickly and strongly and spreads through its underground roots or rhizomes, can undermine the structural integrity of buildings and is expensive to treat.

The Court of Appeal heard that the plant has been present on Network Rail’s land at the affected site for 50 years.

The Court of Appeal ruled that the homeowners were entitled to damages because the plant’s rhizomes had extended beneath both of their properties.

Announcing the decision in London on Tuesday, Sir Terence Etherton, the master of the rolls, said: “Japanese knotweed, and its roots and rhizomes, does not merely carry the risk of future physical damage to buildings, structures and installations on the land. Its presence imposes an immediate burden on landowners who face an increased difficulty in their ability to develop, and in the cost of developing, their land, should they wish to do so, because of the difficulties and expense of eradicating Japanese knotweed from affected land.

“In this way, Japanese knotweed can fairly be described as a natural hazard which affects landowners’ ability fully to use and enjoy their property and, in doing so, interferes with the land’s amenity value.”

Zahra Nanji from Leigh Day said: "This is an important ruling and means that potentially thousands of property owners across the UK will now have an actionable claim for compensation against neighbours who fail to deal with Japanese Knotweed originating on their land.

"Network Rail is only one example of a company which owns property right across the UK and which has neglected to act responsibly in order to tackle the very significant problems associated with Japanese Knotweed. We would encourage all of those affected by Japanese Knotweed to seek legal advice in order to investigate and enforce their potential claims".