Cork County Council will carry out a detailed structural assessment on Doctor’s Bridge in Castlelyons this month, to assess the extent of Japanese knotweed in the area.

The invasive species has the potential to damage the structure as it continues to grow, as the roots can become embedded in it foundations.

Cllr June Murphy brought a motion to Fermoy Municipal Authority’s September meeting last week, calling on the council to remove the knotweed under the bridge. In response, senior engineer Brendan O’Gorman said that due to the extensive spread of the plant on public roads, Cork County Council is currently mapping all reported areas effected by Japanese knotweed.


As the particular motion referred to the bridge, he said, a detailed structural assessment would be carried out. “Knotweed, by its design, can go through a concrete foundation. So that just tells you how vigorous it is. Obviously a bridge is no different to a common structure, so you have to be mindful of the foundations on that bridge. It may be deemed to give a higher priority to this bridge than you would on the side of the road, for example.”

Mr O’Gorman added that Japanese knotweed is going to be a big national issue and that the National Biodiversity Data Centre is working with the EPA, who in turn are liaising with the Department of Housing, Community and Local Government to find ways to improve the situation on the ground.

“Japanese knotweed, by its nature, is being conveyed by water sources so every bridge has the potential to be at risk and then that creates a whole cost issue for Cork County Council and for every local authority in Ireland,” he added.