Riverside property owners – know your rights and responsibilities

If you own land or property alongside a river or other watercourse, including a culvert, this guide is for you. It explains your rights and responsibilities as a riverside property owner

Defining watercourses

A watercourse is any natural or artificial channel that water flows through such as  a river, including where it flows through a culvert, brook, or mill stream. If you own property alongside a watercourse, you are a 'riparian owner'.

Your responsibilities

Some of your responsibilities include:

  • maintaining river beds and banks
  • allowing the flow of water to pass without obstruction
  • controlling invasive alien species such as Japanese knotweed

For further information read, A guide to your rights and responsibilities of riverside ownership in Wales.

Who manages risks to riverside properties?

Natural Resources Wales has powers and responsibilities to manage flood risk from main rivers and the sea, and works with others to maintain and improve main rivers throughout Wales. Our work often affects property owners and people who live near rivers.

Internal Drainage Boards (IDB’s) and unitary local authorities have powers in managing flood risk from ordinary watercourses, surface water and groundwater.


The tidal reaches of many rivers, where the sea flows in and out of the mouth of the river, include public rights of navigation. Harbour authorities may have some control in these reaches. Natural Resources Wales has control over navigation for some waterways only, and will not become involved in disputes, or give legal advice, about navigating any other waterways.

Lead Local Flood Authority role

The unitary local authorities in Wales have powers to manage local flood risk as Lead Local Flood Authorities, according to the Flood and Water Management Act 2010.

Who to contact for help

If you have a query about legislation, the role of risk management authorities, or your rights and responsibilities as a riverside property owner, please call us on 0300 065 3000 or email us at enquiries@naturalresourceswales.gov.uk.