Road collapses into ditch

The whole of Marsh Lane us essentially in a complete state of disrepair with various potholes. The road has collapsed at various points. Most significantly, the top of the road has collapsed into the ditch which needs to function to prevent flooding. Issues with the ditch have caused flooding in Clanfield as recently as last year. The ditch is currently in a far worse state than it was then. The landowner responsible for clearing the ditch states he is unable to do so as it is blocked with a collapsed road and the responsibility to rectify this lies elsewhere. This issue has persisted for a considerable period of time and needs urgent repair.