WN8: Timber sluice

Find out about eligibility and requirements for the timber sluice item.

How much will be paid

£315 per sluice.

Where to use this item

Available for Higher Tier

Only with one of the following management options:

How this item benefits the environment

It will provide a simple mechanism for water level control, which will support raised water levels for restoring or creating habitats.


  • construct the sluice to the size and height agreed with Natural England
  • use pre-cut tongue and groove or chamfered boards, so that they fit tightly together and can easily be re-used or replaced
  • drive the boards far into the ditch sides and ditch bed, so that the bottoms are at least 300mm into impermeable soil (failure to do this will cause leaks)
  • make sure that the boards are long enough to raise the water to the desired level
  • install a first board central to the ditch, making sure it is absolutely vertical
  • drive in subsequent boards on either side of the central board and build towards each ditch bank
  • make sure that the final boards are well keyed into the ditch banks (use horizontal timbers or ‘string pieces’ to prevent them from moving or spreading)

Alternatively, for seepage barriers agreement holders will need to follow these steps:

  • construct the barrier using wooden slats
  • make sure the slats are formed either vertically or horizontally (if they are less than 2m wide)
  • leave a small gap of 2mm between each slat to allow the slow movement of water
  • use posts to support and secure the slats
  • make sure the vertically arranged slats stay in place by using horizontal timbers to brace them to posts on either side of the ditch
  • once the vertical boards are in place, cut out an appropriately sized opening and screw metal channeling to each vertical edge so that it accepts sluice boards
  • install a plank bridge across the back of the board tops on the downstream side
  • secure the plank bridge firmly into the ditch banks (to strengthen the structure and allow access to the drop boards for adjustment)

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 Higher 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

Before applying for this item, applicants should contact the Environment Agency.

Applicants will need to send the following with their application:

  • copies of any advice or consent received from the Environment Agency or other relevant consents, for example from the Internal Drainage Board
  • photographs before works commence

The detailed requirements for this item will be tailored to the Higher Tier site. Higher Tier applicants should discuss and agree these requirements with their adviser.

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.

Use this item on drains, ditches and minor watercourses of appropriate, relatively small size. Use ‘like for like’ materials if replacing an existing timber sluice.

Further information

See the 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.