Land Drainage Act 1991

The Land Drainage Act 1991 governs the management of inland watercourses outside the main rivers system in England and Wales, including consenting of works that affect ordinary watercourses, internal drainage board powers and the duties of riparian owners. The Act is enforced by lead local flood authorities, including London boroughs through their drainage and flood teams, and where applicable internal drainage boards. While urban Greater London has relatively few ordinary watercourses, the Act becomes relevant when developments affect culverted streams, surface water ditches and SuDS outfalls discharging to a watercourse. Practical implications for homeowners include the need for an ordinary watercourse consent before installing or modifying a structure such as a culvert, headwall or pipe outfall. The formal reference is the Land Drainage Act 1991 (c.59) as amended by the Flood and Water Management Act 2010.