RP6: Installation of piped culverts in ditches

Find out about eligibility and requirements for the installation of piped culverts in ditches item.

How much will be paid

£340 per culvert.  

Where to use this item

Available for Mid Tier and Higher Tier


  • in areas targeted to reduce water pollution from agriculture


  • in combination with options for the management and restoration of habitats or features with the support of a Natural England adviser

Where this item cannot be used

  • to replace an existing culvert structure
  • where it may damage an environmental, historical or archaeological feature identified on the Farm Environment Record (FER), the Environmental Information Map or the HEFER
  • where it will restrict the movement of migratory fish or eels
  • without relevant advice or consents from the Environment Agency (EA) or flood defence consenting authority

How this item will benefit the environment

This watercourse crossing will provide access for farm machinery or livestock. This will reduce the disturbance to the watercourse which will help reduce sedimentation and bacterial levels in the water.

If successful there will be:

  • an adequate flow of water
  • runoff of expected flows diverted under a track so farm machinery and livestock can cross
  • farm machinery or livestock crossing tracks safely


  • install a concrete pipe at least 450mm in diameter following the manufacturer’s instructions
  • ensure that pipes have a positive joint to preserve alignment
  • make sure that the pipe lengths give a useable width at ground level that is appropriate for the traffic using the crossing:

    • minimum width of 4m for wheeled traffic
    • less than 4m acceptable for livestock footpaths and bridleways
  • set the pipes on a firm bed and in true alignment
  • make sure that the pipe gradient approximates to that of the ditch bed
  • make sure that the pipe invert (the level of the inside bottom of the pipe) at the upstream end is fractionally below the bottom of the true ditch bed
  • grade the ditch bed downstream if any deepening is needed to accommodate the culvert
  • maintain the culvert for the duration of the agreement, removing debris that builds up so as to maintain flow
  • where the above standard specifications for the culvert are not suitable for the weight of machinery using the crossing, applicants must obtain advice from a drainage or bridge engineer and complete the works in accordance with their advice - applicants are responsible for ensuring the culvert does not collapse
  • ensure that all work:

    • meets relevant British Standards, that is culverts must be constructed using concrete pipes that comply with BS 5911 and BS EN 1916, pipework must be laid in accordance with BS 8000 - examine copies of the most up-to-date standards for guidance
    • complies with the culvert design and operation guide (C689)

Do not:

  • place any resulting spoil on environmental, historic or archaeological features as identified on the FER, the Environmental Information Map or the HEFER

Keeping records

Agreement holders will need to keep the following records and supply them on request:

  • any consents or permissions connected with the work
  • receipted invoices or bank statements where a receipted invoice is unavailable
  • please see the record keeping and inspection requirements as set out in the Mid Tier manual for more detail

Agreement holders will need to keep the following records and supply them with the claim:

  • photographs of the site during the different stages of construction or contracts, invoices or other documents confirming the technical specification for the completed works
  • photographs of the completed works in place and installed
  • if required, advice from a drainage or bridge engineer

Applicants will have to send the following with their application:

  • photographs of the site before the work takes place
  • a copy of advice and consents from the Environment Agency and flood defence consenting authority if required

This item can be used on the same area as RP4 - Livestock and machinery hardcore tracks.

Advice and suggestions for how to carry out this item

The following section gives advice on carrying out this item successfully but does not form part of the requirements for this item.

Consider location and alignment

  • avoid active river areas, particularly meander bends
  • avoid depositional areas
  • make the crossing perpendicular to the river
  • consider floodplain crossings
  • reduce the risk of pollution (such as the release of fine sediments) to protected species and their habitats
  • where necessary, minimise erosion by installing protection measures (such as stone pitching or slabs) downstream of the culvert and on the sides of the ditch

Embedding and maintaining culverts

  • pack a stone-free filling tightly at the sides of the pipe and at least 300mm above it
  • build up the filling in layers up to 150mm thick, making sure it is thoroughly consolidated before adding the next layer
  • follow the manufacturer’s guidance on how deep to cover backfill
  • leave the finished backfill surface so it is crowned above the surrounding levels

Consider using a concrete pad to stabilise the bridge or track over the culvert. Make sure the pad is at least 150mm thick, adding an extra 300mm if the total depth of fill cover over the pipes is less than its diameter.

Try using sloping earth ends as headwalls where appropriate, with the slopes no steeper than 1 in 5. There should be a 1m extension on either end of the culvert beyond the required width of expected traffic.

Further information

Catchment Sensitive Farming (CSF) operates in parts of the country where there are water quality issues linked to farming. The scheme provides farmers with free advice and training. See guidance for further information on CSF support

See the Mid Tier manual or Higher Tier manual to find out more about the scheme and how to apply.

Published 2 April 2015
Last updated 10 March 2017 + show all updates
  1. Updated for 2017 applications.
  2. Information updated for applications in 2016
  3. First published.