Update on Japanese Knotweed in Overstrand

Date published: 1st September 2025

In March, North Norfolk District Council closed the central section of the sea wall in Overstrand following a cliff slip.

The cliff material contained an invasive plant species called Japanese Knotweed, which covers an extensive area of Overstrand’s unstable cliffs and the slope.

Knotweed, a non-native invasive plant species introduced into the UK in the mid-nineteenth century, must be removed by a licensed contractor and disposed of safely to prevent it from spreading. While it is not a threat to public or animal health, it poses a threat to the environment by inhibiting the growth of other plant species.

There is a legal requirement to prevent it from spreading on your land, and removal and disposal must be undertaken by a licensed contractor.

Ordinarily, the Council would simply clear the sea wall (commonly referred to as Overstrand Promenade) of the slip material, to allow for safe passage by pedestrians, but the existence of the plant makes this a much more complicated, and expensive exercise, and one that may have to be frequently repeated.

The Council investigated extensively during the sea wall’s closure, and has obtained expert advice about the issues, devising what it considers to be best course of action.

North Norfolk District Council’s Cabinet will decide upon the proposals on Monday 8 September. 

Proposals for the accessible parts of the seawall include spraying the areas with a herbicide before the plant dies back in the winter, allowing it to be cleared.

For the unreachable parts of the unstable cliff, alternative methods of spraying the knotweed are to be investigated

Cllr Harry Blathwayt, Portfolio holder for Coast, said:  

“Our priority is to maintain a safe environment and we are taking all the steps necessary to ensure this complex issue is dealt with appropriately.

We hope people who use the area will bear with us as we tackle this invasive species and restore safe access to the promenade.” 

Access to and from the beach will remain available via the two sets of steps and the promenade will be reopened after the work has taken place.