Agricultural Odours (Muck Spreading)
During the spring and in the summer after harvesting, councils frequently receive complaints concerning agricultural odours. Generally, the most common source of odour complaints relate to the storing and spreading of bio-solids (sewage sludge), animal manure and slurries (muck spreading). The general practice of incorporating manures and bio-solids into agricultural land is a legitimate practice and is considered the best option for disposal. The spreading of pre-treated sewage sludge is also a perfectly lawful activity and considered the best practicable environmental option for disposal of such wastes.
Although spreading is recognised as standard agricultural practice, and odour must be expected from time to time, spreading should be undertaken in accordance with the best practice guidance given in the DEFRA Code of Good Agricultural Practice, subsection 5.4. Best practice advice from DEFRA includes the following:
If possible, reduce odour and ammonia loss
Use a band spreader or injector to apply slurry. Otherwise, use broadcast equipment with a low trajectory and large droplets. Broadcast slurry (by splash plate) should be incorporated immediately, and at the latest within 6 hours
if solid manure, it should be incorporated as soon as possible and at the latest within 24 hours.
Livestock manures should not be applied
- the soil is waterlogged
- the soil is frozen hard
- the field is snow covered
- heavy rain is forecast within the next 48 hours
The Code also advises that the best conditions for spreading are where air mixes to a great height above the ground, which are typically sunny, windy days, followed by cloudy, windy nights. These conditions cause odours to be diluted quickly.
Farmers are also advised to avoid spreading at weekends, bank holidays, in the evening or in fields close to and upwind of houses, unless it is solid manure that has been well composted, or slurry that is to be band spread, injected or has been treated to reduce odour.
Livestock manures and dirty water should not be spread
- within 10 metres of any ditch, pond or surface water
- within 50 metres of any spring, well, borehole or reservoir that supplies water for human consumption or for farm dairies
- on very steep slopes where run-off is a high risk throughout the year
As there is a great deal of working farmland within Worcestershire, agricultural odours can be a problem with prevailing winds, carrying these odours some distance across fields into residential areas and at times this may result in strong short term agricultural odours within the area, even where best practice has been followed. The duration and intensity of the odour is often difficult to predict depending on weather conditions.
Frequently Asked Questions
How often can someone muck spread?
There is no limit.
Can they do it two days in a row?
Yes.
Please contact the Environment Agency on 0800 807060 or email on enquiries@environment-agency.gov.uk
There is no definite answer but some operations may need a licence which is issued by the Environment Agency. Please contact the Environment Agency on 0800 807060 or email on enquiries@environment-agency.gov.uk
Check notes above which will give some answers but for more information, please contact the Environment Agency on 0800 807060 or email on enquiries@environment-agency.gov.uk
Are there any times spreading is not allowed?
No.
It is purely guidance. It is not law but there could be a case for enforcement if the guidance has been clearly not followed.
Why do farmers have to spread in summer?
A frequently asked question is "Why do farmers have to spread in the summer months. Why not in winter when people are less likely to have windows open or be relaxing in their gardens?" Spreading can only be undertaken in fair weather. Working the soil in wet, cold or frozen ground is often unfeasible. The growing season dictates that most crops are harvested in summer and the incorporation of manures follows almost immediately. This is to replenish the soil ready for the following year.
Why is it that sometimes the smells from spreading are so awful?
Many of the complaints we receive about odour from spreading relate to the spreading of chicken manure (also called chicken litter). This is the material arising from intensive poultry farming where thousands of birds are keep in large sheds.
The smell could be reduced if the chicken manure was pre-treated prior to spreading (eg. by aerobic composting) but this is rarely done in this country because of the costs involved.
Some odours arise from the spreading of sewage sludge. The practice of stockpiling and then spreading of treated sewage sludge is controlled by the Sludge (Use in Agriculture) Regulations 1989. This is regulated by the Environment Agency and overseen by Water UK and Ofwat. Sewage sludge is produced from the treatment of waste and consists of two basis forms, raw primary sludge (basically faecal material) and secondary activated sludge (a living culture of organisms that help remove contaminants from wastewater before it is returned to rivers or the sea). The raw primary sludge is transformed into biosolids using a number of complex treatments such as digestion, lime stabilisation, thickening, dewatering and drying.