Whose Responsibility?
Riparian landowners are responsible for protecting their own banks, and have a legal right to do so. However anyone carrying out works on a river is responsible for any damage they may cause to third party interests. This is why advice and consultation is so important. Even where channel maintenance is carried out by the Environment Agency (Main Rivers) or by a Drainage Board, the channel and banks do not usually belong to them. Their powers are permissive and the work they undertake will be targeted at the common good rather than individuals.

Authorisations
Usually it is illegal to carry out any erosion control work without certain administrative preliminaries. On main rivers a formal consent must be obtained from the Environment Agency before work starts. They have expert staff who are usually pleased to advise on the engineering and ecological aspects of proposals. They publish a number of excellent booklets on the subject. Similar permission is required for works on Drainage Board watercourses. Contact the Clerk to the Board.

However the work is to be done, planning permission may still be needed. Any proposal involving the import of material from offsite may count as tipping and require a Waste Control Licence. If your site lies within an SSSI or other wildlife designation, other formalities will be needed.