Landowner Riparian Responsibility The maintenance of watercourses plays a key role in managing water levels and reducing the risk of flooding. Ordinary watercourses include every river, drain, stream, ditch, dyke, cuts, sluices, culverts, sewer (other than public sewer) and passages through which water flows that do not form part of main rivers. It is not required for water to flow at all times for it to be considered as a watercourse. If there is a watercourse on or near your property boundary, you may be a 'riparian owner'. Information about riparian ownership can be viewed here. We have also made a ‘Riparian Owner’ factsheet which outlines your rights and responsibilities as a riparian owner.