RP12: Check dams
Find out about eligibility and requirements for the check dams item.
How much will be paid
£42 for each dam.
Where to use this item
Available for Mid Tier and Higher Tier
- in areas targeted for the reduction of water pollution from agriculture
- in conjunction with a Feasibility Study or a Catchment Sensitive Farming (CSF) commissioned design plan
Where this item cannot be used
- where it will restrict the movement of migratory fish or eels
- without relevant advice or consents from the Environment Agency (EA) or Internal Drainage Board
How this item will benefit the environment
Check dams or woody debris dams in woodland will slow the movement of water in small natural streams and ditches. They will slow surface water, allowing sediment and other pollutants to settle out, helping to improve water quality and reduce downstream flooding.
- follow the requirements set out in the Feasibility Study or CSF Design Plan
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
Before applying, applicants must seek advice from the Environment Agency and where relevant the Internal Drainage Board to check if consent is required to carry out the planned work. Applicants will have to send the following with their application:
- a copy of any advice or consent received from the EA, and (where relevant) the Internal Drainage Board
- photographs of the existing site
- a copy of the Feasibility Study or CSF design plan (Water-Holding Feature Management Plan)
Related Mid Tier items
This item can be used on the same area as the following items:
- RP11 - Swales
- SW1 - 4m to 6m buffer strip on cultivated land
- SW2 - 4m to 6m buffer strip on intensive grassland
- SW4 - 12m to 24m watercourse buffer strip on cultivated land
- SW7 - Arable reversion to grassland with low fertiliser input
- SW8 - Management of intensive grassland adjacent to a watercourse
- SW11 - Riparian management strip
- WD3 - Woodland edges on arable land
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 several dams
It is likely that several dams will be needed to manage water flows successfully. On small streams, a series of multiple dams should be used that are between 5 to 7 times wider than the channel. This will prevent woody debris becoming dislodged during floods.
Check the dams for silt
The dam must be checked and de-silted regularly to prevent it collecting large amounts of silt.
Design and construction
Agreement holders are likely to need to:
- construct the dam from local soils with a high clay content, timber or stone, as appropriate to the local landscape
- excavate a trench 200 mm deep across the width of the swale
- build up the check dam using 100mm to 600mm grade broken stone, wooden boards, gabions or earth to a height of 500 to 750 mm above the floor of the swale
- build the check dam at the down slope end of the trench and leave the upslope end of the trench empty
- side slopes of the check dam must be a gradient 1 in 2
- check dams must be built into the sides of the swale to avoid water bypassing the structure
- at least 1m to 2m downstream must be protected to dissipate energy from the dam
- place an overflow in the centre of the dam to prevent any scouring of the ends of the dam
The management of water on the land can be improved by using Rural Sustainable Drainage Systems (RSuDS). See the guide to RSuDS for more 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 about CSF support for further information.
Published: 2 April 2015
Updated: 29 March 2016
- Information updated for applications in 2016.
- Update to 'keeping records' section.
- First published.