Our Maintenance Activities

The Board maintains 25km of watercourses and 1 pumping station.

Click here to view our maintenance maps.

Most of the watercourses we maintain are entirely engineered and are not natural waterbodies, they have been cut into the land over centuries for the sole purpose of improving drainage and reducing flood risk. During the summer months many of these watercourses dry out.

The things we maintain are called ‘Board Maintained Assets’ and we aim to carry out some form of inspection or maintenance on them all at least once a year.

We can decide not to carry out maintenance on some parts of the system that link Board Maintained Assets where they have been culverted (piped) without a suitable maintenance agreement in place, or where a development has been allowed to go ahead which prevents maintenance access.

Watercourse Maintenance Activities

– Cutting grass on watercourse banks (Flail Mowing)

– Moving weed from the channel of the watercourse (Weed Control)

– Removing silt from watercourse channels (De-silting)

– Restoring watercourses to design profile (Regrading)

– Piling and other repair works (Stabilisation)

– Controlling bushes interfering with watercourses (Forestry Works)

Pumping Station Maintenance Activities

– Monitoring, control, and data acquisition

– Regular servicing and inspection

– Screen clearance

– Repair and replacement of moving parts

– Building maintenance

Other Asset Maintenance Activities

– Culverts and pipelines repair and maintenance

– Bridge repair and maintenance

– River outfall structure repair and maintenance

– Engineered flood embankments repair and maintenance

Who is responsible for maintaining watercourses?

Ultimately and in all cases riparian owners are responsible for watercourse maintenance. A Riparian Owner is one who owns land or property through which a river, stream, ditch, and watercourse passes, whether piped or not. The origin of the word ‘riparian’ is borrowed from the Latin ‘Riparius’ meaning “related to the river-bank”.

Regardless of boundaries set out in official documents the ‘Ad medium filum’ rule is a rebuttable presumption that where a watercourse forms the boundary to a property, the ownership and responsibility for the watercourse is that of the adjacent land owner’s up to the watercourse’s centre-line.  Importantly, because the land under most public highways is not owned by the Highway Authority the same rule applies to this land, this means that most roadside watercourses are the responsibility of the adjacent owner, not the Highway Authority.

The Riparian Owner has a statutory responsibility to allow the free passage of water by maintaining the banks and bed of watercourses passing through their land. These rules are clearly set out in the Land Drainage Act 1991 (Sections 23 to 25) and local land drainage bylaws.

Board maintained watercourses.

As the Land Drainage Authority, the Board can use its powers to decide to maintain some watercourses for the wider public good at the public expense by raising funds through land drainage rates and council tax. These watercourses are usually larger or arterial watercourses where there is likely to be more flow, but the Board may maintain smaller watercourses for other reasons.

The Board do not own a watercourse unless they own the land under that watercourse which would make them the Riparian Owner. Rarely the Board may ‘vest’ a watercourse by taking ownership of land on which it is situated, however it is important to understand that IDBs do not adopt watercourses. IDBs are not a utility, they are a public authority who provide land drainage and flood risk management functions at the public expense.

In law the Board’s maintenance powers and responsibilities are permissive, this means the Board do have statutory powers to undertake works if they decide, but do not have a statutory requirement to maintain any watercourse where they do not own the land.

Definitive maintenance map

The Board now publish a definitive maintenance map. This map shows watercourses that the Board have decided to maintain on a regular basis. The Board’s staff and contractors will try to undertake some level of maintenance or inspection on all the watercourses every year, however this may not always be possible due to access issues, inclement weather, or funding.

The Board can decide to change the definitive maintenance map at its meetings, because a watercourse was once maintained by the Board this does not imply a precedent for continued maintenance.

Where possible we will publish our planned maintenance regime on this map. We aim to publish this in the early summer before the maintenance season begins. A link to the definitive maintenance map can be found here.


From time to time the Board undertakes work to build new assets or carry out works to improve existing assets. Typically works may involve building new pumping stations but could also involve major works to improve or cut new watercourses. Sometimes the Board will work with partner authorities on larger flood defence schemes.

This type of investment is generally referred to as ‘capital works’. These works can be funded by the Board through land drainage rates and council tax or by capital grant.

The Board is a [Flood] Risk Management Authority or ‘RMA‘. Public RMAs, which include IDBs, the Environment Agency and Local Authorities can apply for National Flood Defence Grant-in-Aid from the Department for the Environment, Food and Rural Affairs (Defra). From time to time, as a public authority the Board will also apply for funding from other government departments. The Board can also ask for funding for ‘local levy’, this is a fund raised through Council Tax by local authorities and managed on behalf of local taxpayers by the Regional Flood and Coastal Committee.

The Board may agree that a developer can pay a contribution to improve or upkeep the local land drainage system which is required to facilitate the development.