Land drainage

See also:

About land drainage

Under most circumstances, landowners are legally responsible for any surface water drainage features on, or adjacent to, their land. Such features can be natural watercourses, such as rivers and streams, or man-made features, such as ditches, drains, culverts (piped watercourses) and sluices etc. Any landowners with any such features on, or adjacent to, their land are legally defined as 'Riparian Landowners' under the Land Drainage Act 1991 (as amended); a definition that brings certain rights and responsibilities.

Landowners should also be aware that; under the Water Resources Act 1991, the Environment Agency also has a responsibility to maintain water flow and carry out flood defence works along any watercourses that have been specifically classified as a 'Main Rivers' or a 'Critical Ordinary Watercourses'.

Additionally, West Sussex County Council and the Highways Agency have responsibilities relating to the drainage of surface water from the public highway.

Back to top

Watercourse responsibilities

There are a number of different categories of watercourse and the category can affect where maintenance responsibilities lie:

Main River

Main Rivers are watercourses that have been specifically classified by the Environment Agency for their strategic drainage importance.

Responsibilities lie with the riparian landowner(s) and enforcement is undertaken by the Environment Agency.

Ordinary watercourse

These are watercourses that have not been specifically classified as Main Rivers by the Environment Agency. Ordinary watercourses may be open ditches or culverted (piped) watercourses. For more information, please:

Highway gullies and drains

These are the drains on adopted roads that remove the excess surface water from the highway only. Responsibilities lie with either West Sussex County Council or Highways England, depending upon the designation of the road.

Sustainable drainage systems

These are surface water drainage systems designed and installed to drain surface water from a developed area. Responsibilities can lie with; the developer, landowner or a management company.


Public sewers and lateral drains are the responsibility of Southern Water.

Private sewers are sewers/cesspits etc. that only serve one property and are within the property boundary. These are the responsibility of the property owner.

For further information on sewer responsibility please see our drains and sewers page.

Back to top

Our powers

Adur & Worthing Councils has no statutory duty with regards to land drainage, except where we are the landowner. We do however have 'permissive powers' to help ensure that:

  • Watercourses are properly maintained, across the district
  • Riparian Landowners abide by the law and undertake their riparian responsibilities

The councils' 'permissive powers' are only generally used when landowners have demonstrated an unwillingness to fulfil their riparian responsibility to appropriately maintain their watercourse.

Back to top

Altering, infilling or culverting an ordinary watercourse

Under the Land Drainage Act 1991 (as amended) watercourses within Adur and Worthing must not be created, altered, infilled, or culverted or 'discharged into' without the prior written consent of Adur & Worthing Councils.

You can apply for consent to undertake any of these actions, by completing and submitting a consent application:

If you are a riparian landowner you have a responsibility to maintain the free-flow of your watercourses at all times. Altering, infilling or culverting a watercourse will impact the free flow of water, and may leave you liable should flooding occur as a result of your actions. Creating a new watercourse could create new problems to other landowners, specifically if you are directing water somewhere new.

Back to top

Reporting blocked, infilled or a poorly maintained watercourse

Open ditches can be described as 'poorly maintained' if:

  • the bed and banks of the watercourse are so heavily vegetated that they are preventing the free-flow of water
  • the silt level in the watercourse has built up so much that insufficient capacity remains for water

Additionally, trees, rubbish, or other debris that has fallen into a watercourse can cause an obstruction to the free-flow of water and will therefore require removal. Culverted (piped) watercourses are more prone to blockages than open ditches. Culvert blockages can be either within the culvert, or at the culvert entrance. Culverts must be regularly checked and cleared by the landowner or the relevant authority.

If you have any concerns regarding the condition of a watercourse please contact:

Back to top

Landowner, householder or business flooding responsibilities

Whether you are a landowner, householder or business, you may have responsibilities for managing your own flood risk.

For more details, please see the West Sussex County Council website for details including riparian (stream or river bank or banks of a natural course of water) ownership issues:

Back to top

Page last updated: 07 November 2019