Network Rail has lost an appeal against a decision that it should compensate two homeowners whose properties were affected by Japanese knotweed on its land.
The judgement is likely to affect other landowners, including transport infrastructure operators.
The Court of Appeal ordered the rail infrastructure operator to pay compensation to Stephen Williams and Robin Waistell on the grounds that the underground roots (‘rhizomes’) of knotweed on its land had encroached under their properties.
The original decision found that Network Rail’s treatment of the knotweed was inadequate and unreasonable and in breach of its duty as a landowner.
A Network Rail spokesperson said: 'As many gardeners know, Japanese knotweed is invasive and requires several years of treatment to remove. Once identified, Japanese knotweed growing on our land is entered into a treatment programme. We will continue with this established regime, which complies with legislation and helps us run a safe, reliable railway.
'Network Rail is aware of today’s ruling by the Court of Appeal and is considering its implications.'
Three Court of Appeal judges, headed by Sir Terence Etherton, Master of the Rolls, ruled that the two homeowners could not claim compensation for a drop in the value of their homes, as the original decision had found, but because the encroachment of the rhizomes had ‘diminished the claimants’ ability to enjoy the amenity and utility of their respective properties’.
Sir Terence 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.
He added that 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’.
The judgement pointed out that Japanese knotweed is a hardy bamboo-like plant that grows quickly and strongly and can block drains; disrupt drain runs; grow between slabs of concrete drives; disrupt brick paving; undermine garden walls; and overwhelm poorly built outbuildings and conservatories.
It is also a pernicious weed that is very difficult to eradicate from the land on which it grows.