On the 27th January 2021 Lesley Griffiths, Minister for Environment, Energy and Rural Affairs for Wales announced her decision to introduce agricultural pollution regulations, which will apply to the whole of Wales.

The Water Resources (Control of Agricultural Pollution) (Wales) Regulations 2021 will apply from 1st April 2021 for an initial set of measurements. The remainder will be phased in over a period of 3 years.

In summary, the regulations include the following requirements:

  • Nutrient management planning;
  • Sustainable fertiliser applications linked to the requirement of the crop;
  • Protection of water from pollution related to when, where and how fertiliser are spread; and
  • Manure and silage storage standards.

The Welsh Government has made support available to farmers through the Rural Development Plan’s Farm Business Grant (FBG) and Sustainable Production Grant (SPG) schemes to improve nutrient management and to reduce farm pollution.

  • The next FBG application window will be open between 1 March and 9 April 2021.
  • The next SPG window opens on 1 February and will close on 12 March.

Further information can be found at: https://gov.wales/rural-grants-payments

The new regulations will replace the existing NVZ regulations.

From 1 April 2021

Storage of manure and silage

  • 14 days’ notice must be given to NRW before construction begins on a new or improved slurry or silage store (this change applies from 28 April).
  • Other than the requirement to notify NRW before construction of a store begins, the silage storage requirements will remain the same (as SSAFO).

Exempt Structures

  • Installations that were in use or built before March 1991 or where a contract for construction was entered into before March and completed before September 1991 are “exempt structures”.
  • An old store may be used, but the storage capacity requirements of these Regulations must still be met by 1 August 2024.

Controlling the spreading of nitrogen fertiliser (includes manufactured nitrogen fertiliser, slurry and other organic manures):

  • If you intend to spread nitrogen fertiliser you must first inspect the field to consider the risk of nitrogen getting into surface water.
  • You must not spread nitrogen fertiliser on land if there is a significant risk of nitrogen getting into surface water, taking into account factors such as weather and slope.
  • Mandatory buffer zones will be established (as per existing cross compliance requirements).

Closed periods for spreading manufactured nitrogen fertiliser

  • on grassland, from 15 September to 15 January*
  • on tillage land, from 1 September to 15 January*

*Exemptions apply which are explained in the full guidance.

Incorporation of manure

  • Organic manure applied to bare soil must be incorporated within 24 hours in most circumstances.*

*Exemptions may apply eg. if precision spreading equipment is used.

From 1 January 2023

Risk Maps

  • If you intend to spread manure on the holding you must produce and maintain a risk map which highlights the areas on which spreading may cause pollution, including buffer zones and surface waters.
  • Sites suitable for field heaps should be marked if manure is to be stored in field heaps.

Storage of Organic Manure

Other than slurry, any organic manure must be stored:
– in a vessel;
– in a covered building;
– on an impermeable surface; or
– in a free standing temporary field heap

Temporary Field Heaps

  • Rules on the placement of manure field heaps will apply to minimise the risk of any leaching and run off reaching waterbodies.

Nutrient Management Planning

  • A Nutrient Management Plan must be established for any nitrogen fertiliser application, which includes the soil nitrogen supply and the requirement of the crop.

Import/Export of Manure 

  • Any import/export of manure onto/off the holding must be recorded.

Nutrient applications

  • Fertiliser applications must not exceed specified crop limits.
  • Fertiliser must be applied as accurately as possible and spreading trajectory must be below 4 meters from the ground.


  • Records associated with Nutrient Management Plans and fertiliser applications must be kept.
  • Exemptions from certain requirements will apply to extensive farms.

Holding limit 

  • A limit of 250kg per individual hectare is applied to the spreading of organic manure for any 12 month rolling period.
  • No more than 170kg of nitrogen from manure can be applied each year, averaged across the holding, either directly deposited by the animal or by spreading.

From 1 August 2024

Closed periods 

  • The spreading of slurry (and other manures but not farmyard manure) will be prohibited during the following periods (certain exemptions will apply*):
Soil Type Grassland Tillage Land
Sandy or shallow soil 1 September – 31 December 1 August – 31 December
All other soils 15 October – 15 January 1 October – 31 January
  • Spreading after the closed period until the end of February will be limited to 30 cubic metres per hectare (8 tonnes per hectare of poultry manure) at any one time, and there must be at least three weeks between each spreading.

*Details of exemptions are provided in the full guidance

Slurry Storage capacity

  • 5 months of slurry storage will be required for any slurry produced by any livestock, other than pigs or poultry.
  • For slurry produced by pigs and poultry, 6 months of slurry storage will be required.

Note: the rainfall figures and calculations used to determine the storage you will need to meet the requirements of the new regulations differs from those of the existing SSAFO regulations. Because of this, the difference between 4 months SSAFO and 5 months required by the new regulations is not necessarily equivalent to an additional month of storage. In some cases, such as in low rainfall areas, the new requirement may be lower than the existing SSAFO requirement. Where the requirement in the new regulations is greater, you should assess the most effective way to meet the new storage requirement, such as improved clean and dirty water separation.

Irrespective of the minimum storage requirement, you must ensure you have sufficient storage available to enable you to comply with the other requirements of the regulations.

Detailed guidance documents will be published on the Welsh Government website providing a step-by-step approach to the implementation of the regulations.  The latest information can be found on the following pages: https://gov.wales/land-management

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