Watercourse management

If you are planning to undertake works within a watercourse within the UK, you need permission to do so by law. It is essential that anyone who intends to carry out works in, over, under or near a watercourse, contacts the relevant flood risk management authority to obtain the necessary consent before starting the work. In relation to works on an ordinary watercourse, the legal provisions are as follows:

Section 23(1) of the Land Drainage Act 1991 states"No person shall:

(a)   erect any mill dam, weir or other like obstruction to the flow of any ordinary watercourse or raise or otherwise alter any such obstruction, or

(b)   erect a culvert in an ordinary watercourse, or

(c)    alter a culvert in a manner that would be likely to affect the flow of an ordinary watercourse,

without the consent in writing of the drainage board concerned.”

Ordinary watercourses include every river, drain, stream, ditch, dyke, cuts, sluices, culverts, sewer (other than public sewer) and passage through which water flows that do not form part of main rivers. The Environment Agency remains responsible for regulating activities affecting the coast and main rivers. It is not required for water to flow at all times for it to be considered as a watercourse.

For ordinary watercourses in Cambridgeshire, outside an Internal Drainage Board (IDB) area, the relevant authority is Cambridgeshire County Council (CCC). The consent granted by CCC for working on a watercourse is known as "Land Drainage Consent”. Some ordinary watercourses are under the jurisdiction of an IDB, and the IDB will be the consenting body for these watercourses. Changes to structures (e.g. dams, weirs, culverts or other such obstructions) that are already in place will also need consent from CCC or the IDB.

When considering if proposed works to an ordinary watercourse will require consent, you should consider whether the proposed structure would affect the flow of the watercourse when the channel is full. If the answer to this is yes, then consent from CCC or the IDB will be required. Consent will be required irrespective of whether works are permanent or temporary. Please note that the maximum length of time that can be consented for a temporary structure is 12 months.

The reason for the consenting process is to ensure that any proposed works do not endanger life or property by increasing the risk of flooding nor cause harm to the water environment and nature conservation. CCC will consider each application to work on a watercourse on its own merits, but it is CCC policy to keep watercourses as open channels without obstructions to flow wherever is reasonably possible. We will not permit culverting of a watercourse where there is no genuine need, or where the inclusion of a culvert would lead to an increase in flood risk in the area. In all cases, where it is appropriate to do so, applicants must provide adequate mitigation measures.

You are advised to contact the council to check whether your works will be deemed to affect an ordinary watercourse - floodandwater@cambridgeshire.gov.uk

In relation to works to culverts, our Culvert Policy should be followed.

Size: 33KBFile format: pdf

Pre-application advice

Ordinary watercourse consenting pre-application charging schedule.

Pre-application enquiry type Access culverts less than 6m for a single householder (cost per structure including VAT at 20%) All other structures, including, but not limited to access culverts (cost per structure including VAT at 20%)
Written advice in response to a written enquiry n/a £60
Meeting and written advice with officer at the council office. General discussion of requirement, provision of info and sign-posting of further information sources; support and advice available  n/a £90
Meeting on site with an officer followed by written advice £60 £120
Additional work £60 per hour plus travel expenses (£0.45 per mile)

We strongly encourage pre-application discussions and potentially site visits to discuss the appropriateness of your proposed plans and to ensure that everything you need to submit is provided when the application is made.

Making an application for ordinary watercourse works

Please read the application guidance document and apply online using the form below.

Ordinary Watercourse Consent Application Form Guidance - June 2019180KBpdf
Size: 180KBFile format: pdf

Who is responsible for drains and sewers?

Homeowners or occupiers are responsible for the drains up to their property boundary. Water and sewerage companies are responsible for:

  • all public sewers
  • private sewers and lateral drains that connect to the public sewer

Water and sewerage companies are not responsible for private sewers that:

  • are connected to a private pumping station and treatment works
  • carry water directly to a watercourse, like a river, or into the ground (eg a soak away).

Landowner riparian responsibility

If you own land adjoining, above or with a watercourse running through it, you have certain rights and responsibilities. In legal terms you are a “riparian owner”.

If you rent the land you should agree with the owner who should manage these rights and responsibilities. Smaller watercourses, ditches and drains, known as "ordinary watercourses" play a crucial role in managing flood risk to people and property in Cambridgeshire. That is why it is important to ensure that they are well maintained and kept free from debris, obstructions and do not become overgrown.

Cambridgeshire County Council, under the Flood and Water Management Act (2010), is a Lead Local Flood Authority, and responsible for regulating ordinary watercourses outside of Internal Drainage Board’s rateable areas

Rights and responsibilities of a riparian owner

A watercourse is defined as any channel through which water flows. It may range from a reasonable-sized ditch with a constant flow to nothing more than a depression which carries water infrequently. Within the meaning of the Act “watercourses” may also be piped. Whilst watercourses may take runoff from the highway, the originating flow will normally be from a land drainage source.

Watercourses are classified as either:

Main Rivers:

Managed by the Environment Agency. The responsibility for their maintenance and repair lies with the “Riparian Owner(s)”, although the EA also have powers to maintain and improve them. Further information on your responsibilities regarding Main Rivers is available on the GOV.UK website.

Ordinary Watercourses:

The responsibility for their maintenance and repair lies with the “Riparian Owner(s)”

Awarded Watercourses:

The responsibility for the maintenance lies with the Local District or City Councils (or another relevant authority).

The expression “riparian rights” refers to those common law powers and duties relating to the use of water associated with the ownership of the bank or bed of a watercourse. The deeds to a property may indicate who the riparian owner is but this is not always the case. The law therefore presumes, in the absence of contrary evidence, that land adjoining a watercourse includes the watercourse. If there is nothing specific in the property deeds and unless there is something to establish contrary intention, the riparian owner is responsible for the watercourse. A ditch alongside a road is normally owned by the adjacent landowner.

Roadside Ordinary Watercourses:

There are 2 categories of roadside ditch:

  • A ditch on either the field side or road side of fences and hedges taking land drainage as well as highway drainage, which under common law is the responsibility of the adjacent Riparian
  • A ditch constructed by the Highway Authority, or wholly within the freehold land owned by them, solely used for draining the highway, which is the responsibility of the Highway

Under the Highways Act 1980 the Highway Authority has a prescriptive right to drain the highway to any adjoining roadside ditches. Rural roads rely to a great extent on ditches to remove water and their effectiveness is vital to keeping them in good condition. Common Law imposes a duty on the owner of land adjoining a highway to maintain these ditches that provide natural drainage for both the land and highway. In the vast majority of cases the responsibility for ditch maintenance rests with the adjacent landowner.

Different watercourses are regulated by different Risk Management Authorities (RMAs).

The Environment Agency is the RMA for watercourses designated as ‘Main River’. If you are planning to carry out work on, over, under or near a main river, you will need to discuss your plans with them.

Internal Drainage Boards (IDBs) are the RMA for ordinary watercourses within their rateable areas. If you are planning to carry out work near or within an ordinary watercourse in an IDB area, you will need to discuss your plans with them before you start work.

If you are planning any work near or within an ordinary watercourse but outside of an IDB rateable area you need to speak with the Flood Risk and Biodiversity Team within Cambridgeshire County Council to discuss your plans. The County Council has taken on the role for consent-ing and enforcement of works to ordinary watercourses in non IDB areas since 6th April 2012.


If your land boundary is next to a watercourse it is assumed you own the land up to the centre of the watercourse, unless it is owned by someone else. If a watercourse runs alongside your garden wall or hedge you should check your property deeds to see if your wall or hedge marks the boundary. If the watercourse marks the boundary it is assumed you own the land up to the centre of the watercourse.

If you own land with a watercourse running through or underneath it, it is assumed you own the stretch of watercourse that runs through your land.

Occasionally a watercourse especially an artificial one, will be the responsibility of a third party. This should be noted in your deeds.

Water should flow onto or under your land in its natural quantity and quality. This means that water should not be taken out of a watercourse if it could lead to a lack of water for those downstream. It also means that a person cannot carry out activities that could cause pollution to a watercourse.

You have the right to protect your property from flooding, and your land from erosion. However you must get your plans agreed by the relevant Risk Management Authority (RMA) before you start work.

Please remember these rights are affected by your duty to other riparian landowners, the community and the environment.

You must let water flow through your land without any obstruction, pollution or diversion which affects the rights of others. Others also have the right to receive water in its natural quantity and quality. Riparian owners all have the same rights and responsibilities.

You must accept flood flows through your land, even if these are caused by inadequate capacity downstream. A landowner has no duty in common law to improve the drainage capacity of a watercourse he/she owns.

You should keep the banks clear of anything that could cause an obstruction and increase flood risk, either on your land or downstream if it is washed away. You are responsible for maintaining the bed and banks of the watercourse and the trees and shrubs growing on the banks. You should also clear any litter, debris or animal carcasses from the channel and banks, even if it did not originate from your land.

You should always leave a development-free edge on the banks next to the watercourse. This allows easy access to the watercourse in case any maintenance or inspection is required.

In some areas local byelaws exist which explains what you can or cannot do within certain distances of a watercourse. For more information on works near watercourses contact the relevant risk management authority.

You must keep structures such as culverts, trash screens, weirs and mill gates, clear of debris.

Discuss the maintenance of flood defences such as walls and embankments on your property with your RMA. They may be vital for flood protection.

You should not cause obstructions, temporary or permanent that would stop fish passing through.

Please help us to protect water quality. Do not use riverbanks to dispose of garden or other waste where it could be washed into the river. This includes grass clippings, which pollute watercourses.

You are responsible for protecting your property from water that seeps through natural or manmade banks. Where this damages a flood defence, your RMA may require you to pay for repairs.

Your property may include a watercourse that runs through a culvert. You have the same responsibilities for the upkeep of a culvert as if it was an open watercourse.

If you do not carry out your riparian responsibilities, we can request you to maintain the watercourse and you could face legal action under The Public Health Act 1936, The Land Drainage Acts 1991 and 1994, the Water Resources Act 1991 and the Environment Agency Land Drainage Byelaws 1981.

The same information about the rights and responsibilities of a riparian owner is also available in the leaflet below.