A slurry store and the agricultural notification route
Part 6 prior notification covers most farm slurry stores, with a 28 day period and a narrow council role. The 400 metre protected building rule and the separate storage regulations decide the rest.
A slurry store on a holding of five hectares or more is usually permitted development, but it is permitted development with a procedure attached. You still have to apply to the council for a determination as to whether its prior approval is needed for the siting, design and external appearance, and you cannot start until that is resolved or 28 days have passed. The slurry store planning notification route sits in Part 6 of Schedule 2 to the Town and Country Planning (General Permitted Development) (England) Order 2015. A second, separate set of rules governs how the store is built and when the Environment Agency has to be told.
Permitted development for agricultural buildings and works
Part 6 splits by holding size. Class A applies to agricultural units of five hectares or more and allows the erection, extension or alteration of a building reasonably necessary for the purposes of agriculture on that unit. Class B applies to units of between 0.4 and five hectares and is much tighter: it permits the extension or alteration of an existing agricultural building and certain works, but not the erection of a new one. Below 0.4 hectares there are no Part 6 rights at all.
For Class A the limits that matter to a slurry store are these. The ground area covered by the works, together with other Part 6 development within 90 metres carried out in the previous two years, must not exceed 1,000 m². Height is capped at 12 metres, falling to three metres within three kilometres of the perimeter of an aerodrome. Nothing may be built within 25 metres of the metalled surface of a trunk or classified road.
Then the restriction that decides most slurry schemes. A building for the accommodation of livestock, or a building or structure for the storage of slurry or sewage sludge, is not permitted development within 400 metres of the curtilage of a protected building. A protected building is broadly a permanent building normally occupied by people, with carve-outs for buildings on the same agricultural unit and for buildings on another holding that are used for agriculture. Measure it properly, from curtilage rather than from the wall of the house, and measure it to the nearest edge of the structure including any earth bank.
The prior notification procedure and its 28 day period
The application is short. You send the council a written description of the proposed development, a plan showing the site, and the fee set by the national fee regulations, which is indexed annually, so check the current schedule before you send it.
What happens next is a determination of whether prior approval will be required for the siting, design and external appearance of the building. Three outcomes end the wait: the authority tells you prior approval is not required, the authority grants prior approval, or 28 days pass from the day after receipt without the authority notifying you of its decision either way. Only then may work begin, and it must then be carried out in accordance with the details submitted or approved.
Do not treat the 28 days as automatic cover. If the council writes within the period to say prior approval is required, you need its approval of the details before starting, and there is no deadline on that second stage equivalent to the 28 days. Councils in sensitive landscapes almost always require approval, so build the extra round into the programme.
Design and siting determination and what it covers
The council's jurisdiction at this stage is narrow. It can control siting, design and external appearance. It cannot decide whether the store is needed, refuse on agricultural policy grounds, or impose a general planning balance of the sort you would get on a full application.
That narrowness cuts both ways. A council unhappy about smell towards a village cannot refuse on odour alone, but it can require a siting further from the receptor, which produces the same practical result. Expect it to ask for a position screened by existing buildings, a colour and finish in recessive dark greens or greys, and a profile that reads as agricultural rather than industrial. On a sloping holding, siting below the ridgeline usually settles the argument quickly. The same thinking applies to other farm engineering works, including a farm reservoir or irrigation lagoon, where cut and fill levels do more for landscape impact than any amount of planting.
Separation from dwellings and watercourses
Two separation rules operate at once and they are commonly confused.
The 400 metre rule is a planning rule. It removes permitted development rights for slurry storage close to a protected building, and if you fall inside it the answer is a full planning application, not a notification.
The 10 metre rule is an environmental rule. Under the Water Resources (Control of Pollution) (Silage, Slurry and Agricultural Fuel Oil) (England) Regulations 2010, a new or substantially enlarged slurry store must not be sited within 10 metres of inland freshwaters or coastal waters. Local circumstances often push that much further, particularly in a groundwater source protection zone or where land drains run to a watercourse.
| Constraint | Source | Effect if breached |
|---|---|---|
| 400 m from a protected building | GPDO 2015 Part 6 | No permitted development rights, full application needed |
| 1,000 m² ground area | GPDO 2015 Part 6 | No permitted development rights |
| 12 m height, 3 m near an aerodrome | GPDO 2015 Part 6 | No permitted development rights |
| 10 m from inland or coastal waters | SSAFO Regulations 2010 | Store cannot lawfully be used |
| 14 days notice before first use | SSAFO Regulations 2010 | Offence to use the store |
Storage rules and the regulator's requirements
The construction standards sit outside planning entirely. Under the 2010 regulations the store has to be built to the relevant standard, which in practice means the British Standard for slurry and silage structures, and the Environment Agency must be given at least 14 days notice before a new, substantially reconstructed or substantially enlarged store is first used. That notice is not a planning matter and the council will not remind you about it.
Capacity is a separate question again. If the holding lies in a nitrate vulnerable zone, the storage capacity requirement is set by the nitrate rules rather than by anything in the planning permission, and the Farming Rules for Water apply across England regardless of zone. Design the capacity for the regulatory requirement first, then check the resulting footprint against the 1,000 m² Part 6 limit, because it is easy to design a compliant store that has lost its permitted development rights.
Odour, flies and neighbour complaints
Odour is the issue that generates letters, and the notification route gives neighbours very little purchase on it. That is worth knowing before you choose the site rather than afterwards.
Statutory nuisance under Part III of the Environmental Protection Act 1990 remains available to the council's environmental health team whatever the planning position. A store sited to catch the prevailing wind towards housing is a long-term liability even where the 400 metre rule is satisfied. Covers, a stirring regime timed away from weekends, and a bund planted on the receptor side all help, and none of them is expensive compared with moving a store later.
Where a full application is needed, an Odour Assessment with a receptor plan and a wind rose is the document that answers objections. Councils usually expect a suitably qualified author for that work and professional review is strongly advised.
Where a full application becomes necessary
You are into a full planning application if the store sits within 400 metres of a protected building, if the ground area exceeds 1,000 m², if the holding is under five hectares, if the height exceeds the Part 6 cap, or if the land is not an agricultural unit at all because the agricultural use has lapsed. National Park and National Landscape designations do not remove Part 6 rights outright, but they bring extra constraints under the Order, so check the schedule rather than assuming.
A full application changes the document set. You will need a Planning Statement that justifies the store against the development plan's rural economy and landscape policies, a site plan with levels, elevations, a landscape scheme, and usually the odour work described above. Set out the agricultural need plainly, with herd numbers and the storage period the nitrate rules require, because that is the evidence that carries a countryside location.
The drawings and details to submit
Keep the pack tight and complete. A location plan at a recognised scale with the application site edged red and the holding edged blue. A site plan showing the store, any ancillary pump or separator, the access route for a tanker, levels, and the measured distance to every protected building within 500 metres. Elevations and sections with finished levels, materials, colour and any cover. A short note on construction standard and the notice to be given to the Environment Agency.
Include the measurements on the drawing rather than in a covering letter. A case officer who can read the 400 metre distance off the plan has no reason to spend the 28 days checking it, and that is the difference between starting in a month and starting in three. Browse the report types on PlanScope if you want to see what a full application for a farm building would need alongside the drawings.
This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.
Frequently asked questions
How long does a Part 6 prior notification take?
The council has 28 days from the day after it receives the notification to tell you whether prior approval of siting, design and external appearance is required. If it says no, or says nothing in that window, you may start. If it says approval is required, you need that approval first and no 28 day limit applies to the second stage.
How is the 400 metre distance to a protected building measured?
From the curtilage of the protected building, not from its wall, to the nearest part of the proposed structure including any earth bank or bund. A protected building is broadly a permanent building normally occupied by people, with exceptions for buildings on the same agricultural unit and farm buildings on another holding.
Do I need to tell the Environment Agency about a new slurry store?
Yes. The 2010 silage, slurry and agricultural fuel oil regulations require at least 14 days notice before a new, substantially reconstructed or substantially enlarged store is first used, and set construction and siting standards including a 10 metre separation from inland freshwaters or coastal waters. That duty is separate from planning.
Can the council refuse a slurry store on odour grounds under Part 6?
Not directly. At the determination stage its powers cover siting, design and external appearance only, so it cannot refuse on general planning or odour policy. It can require a different siting, which often achieves the same outcome, and the environmental health team retains its statutory nuisance powers whatever the planning position.
What if my holding is smaller than five hectares?
Class B applies to units between 0.4 and five hectares and does not permit the erection of a new building, only the extension or alteration of an existing one plus certain works. Below 0.4 hectares there are no Part 6 rights. In both cases a new slurry store needs a full planning application.
Sources and further reading
This article is general guidance about the planning system in England and, where stated, the rest of the UK. It is not legal or professional advice. Check your local planning authority’s validation requirements and take professional advice for your specific site.