RP13: Yard - underground drainage pipework
Source: gov.uk (2025-07-03)

Find out about eligibility and requirements for the yard - underground drainage pipework item.

This item is part of Capital Grants 2025. You must read the Capital Grants 2025 guidance (https://www.gov.uk/government/publications/capital-grants-2025) to understand the rules and how to apply. If you’re applying for this item as part of a Countryside Stewardship Higher Tier (CSHT) application, you must read the CSHT applicant’s guide (https://www.gov.uk/government/publications/countryside-stewardship-higher-tier-csht) to understand the rules and how to apply.

How much you’ll be paid

£2.02 per metre (m).

How this item benefits the environment

This item improves existing outdoor yards, reducing the risk of runoff and water pollution.

This item can help you protect, recover and improve biodiversity on your land.

Where you can use this item

You can only use this item with support from Catchment Sensitive Farming (https://www.gov.uk/guidance/catchment-sensitive-farming-reduce-agricultural-water-pollution) in areas targeted to reduce water pollution from agriculture

Catchment Sensitive Farming provides advice where there are water quality or flood risk issues linked to farming.

You’ll need to get relevant advice, permits or consents from the Environment Agency, (https://www.gov.uk/guidance/check-if-you-need-an-environmental-permit) lead local flood authority or internal drainage board (https://www.ada.org.uk/member_type/idbs/) before you start any work.

You must also contact your local planning authority to check if planning permission is needed.

You cannot use this item on:
- covered or indoor yards
- historic or archaeological features identified in your Historic Environment Farm Environment Record (https://hefer-data.org.uk/) (HEFER)
- areas of wildlife interest identified on your Farm Environment Record (FER) or on MAGIC (https://magic.defra.gov.uk/MagicMap.aspx)
What you must do to use this item

You must:
- install 100 millimetres (mm) or 150mm (internal diameter) drains
- excavate trenches that are at least the width of the pipes outside diameter plus 300mm
- lay pipes on clay or sand that is at least 100mm thick
- avoid settlement of solids or semi-solid material in water drains by laying pipes to a fall of no less than 1 in 60 for 100mm internal diameter pipes, or no less than 1 in 100 for 150mm internal diameter pipes
- place inspection pits at no more than 90m apart in straight lines
- only use uPVC pipes with sealed joints and join them according to the manufacturer’s instructions
- backfill the hole when the pipe is laid to at least 600mm in areas without traffic or 900mm in areas with traffic
- use compacted excavated material such as smooth stone, clay or sandy soil for backfill and remove any surplus
Where it is not possible to backfill to 600mm or 900mm in areas with traffic, you must wrap the pipes in plastic sheeting and encased in at least 150mm of concrete.

Evidence you must keep

You must keep written support from your Catchment Sensitive Farming adviser and provide it with your application.

You must also keep and provide with your 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
- any consents or permissions connected with the work, including from the local planning authority
If you do not need consent or permission from your local planning authority, you must provide evidence to show this. This can be a:
- letter from the authority confirming you do not need permission
- note of a telephone conversation with a local authority representative, with the name, date, and time of the call
- link to online guidance or printout of guidance text which shows you do not need permission
You must also keep and provide on request:
- receipted invoices or bank statements where a receipted invoice is unavailable
- photographs of site before works start
Read the record keeping and site visit requirements in the Agreement holder’s guide: Capital Grants, Higher Tier capital grants and Protection and Infrastructure grants (https://www.gov.uk/government/publications/agreement-holders-guide-capital-grants-higher-tier-capital-grants-and-protection-and-infrastructure-grants-2025) for more information.

If you’re applying for this item as part of a Countryside Stewardship Higher Tier (CSHT) application, read the record keeping and site visit requirements in the CSHT agreement holder’s guide (https://www.gov.uk/government/publications/countryside-stewardship-higher-tier-csht).

Other items you can use with this item

You can use this item with these items:

RP5: Cross drains (https://www.gov.uk/countryside-stewardship-grants/cross-drains-rp5)

RP14: Yard inspection pit (https://www.gov.uk/countryside-stewardship-grants/yard-inspection-pit-rp14)

RP15: Concrete yard renewal (https://www.gov.uk/countryside-stewardship-grants/concrete-yard-renewal-rp15)

Advice to help you use this item

The following advice may help you to use this item, but you do not have to follow it to get paid. It’s not part of this item’s requirements.

British Standards

Check to make sure the work meets relevant British Standards. (https://www.bsigroup.com/en-GB/products-and-services/standards/)

Separating water and slurry

Read about separating water and slurry at the Rivers Trust (https://s3.eu-west-2.amazonaws.com/assets.theriverstrust.org/Legacy-uploads/Organic-by-products-6.0-1.pdf).