Slurry separators: change in guidance for farms in England
To guarantee that your farming business is compliant with Defra’s regulations, check out our review of the rules for slurry separators
The slurry systems on your land, even if previously approved by the Environment Agency (EA), could be noncompliant today if you missed Defra’s change in guidance.
Despite being in force for a year and a half now, few farmers are thought to be aware of the adjustment by Defra which was introduced to slurry separators (the process of using a mechanical separator to manage slurry) in October 2023.
How have slurry separator rules changed?
The key clarification is that farms must now have enough slurry storage capacity to meet the minimum storage requirements without using a separator – i.e., storage for at least four months’ worth of unseparated slurry on all farms (or more if spreading slurry in the other eight months is likely to cause pollution). Farms in Nitrate Vulnerable Zones (NVZs) must have at least six months’ storage for pigs and poultry, and five months for cattle, sheep, goats, deer, and horses, all without separation.
The change in guidance does not ban slurry separators, which offer numerous handling and environmental benefits. This includes less crusting in slurry stores, easier transport, more precise fertilisation, and reduced ammonia volatilisation after spreading. Therefore, the CLA was curious why Defra would appear to de-incentivise their use.
We learnt that rather than tightening legislation, the ‘new’ guidance re-states existing law. Previously, Defra had instructed the EA not to enforce against those using slurry separators to meet minimum storage requirements, even though this was technically illegal. Ahead of offering the Slurry Infrastructure grant, Defra reviewed this position, and decided it was untenable. Civil servants alleged that broken-down separators were not being repaired promptly, with pollution occurring due to insufficient storage capacity. Neither Defra nor the EA could provide data to support this argument, but its validity is separate to the legal position.
Liquid leaching from stackable manure is classified as slurry. The new guidance states that all stackable solids must be collected, stored on an impermeable surface, and kept under an impermeable cover such as a tarpaulin or in a barn. Again, this is not a new regulatory standard, but one enforced less often in the past. Uncovered field heaps without an impermeable base are only permitted for “short periods when preparing to spread the material to land”. When spreading separated solids and liquids, be aware their nutrient concentrations will differ from the unseparated slurry.
Ensure that your business is compliant
You may be concerned about an inspection before you have had time to upgrade your storage capacity, but remember that the EA follows an advice-first approach. Inspectors usually provide a short notice period to become compliant before issuing fines (CLA members can read more on pages 20-22 of the January edition of Land & Business magazine). The Slurry Infrastructure grant has previously funded upgrades, but Defra is not expected to decide whether to offer a third round before early summer.
The apparent change in the regulatory baseline is yet another reminder that current regulations are confusing and in need of reform. The CLA continues to press Defra to simplify the controls on agricultural pollution, and convert them into a single, streamlined set that is easier for farmers and regulators to use.