Slurry: spreading good practice

If you have livestock (particularly cows) on your farm, then slurry will be a part of your working life. It plays a vital role in the cultivation of your land, but you’ll also know that it can be one of the most dangerous things on your farm if mismanaged.

Deaths from slurry-related incidents are sadly not uncommon, there have been 27 over the last 15 years. Back in 2016 a farm worker was tragically killed while trying to rescue a teen colleague who had fallen into a slurry tank in Leicestershire. And in Northern Ireland three members of the same family died in the same slurry related incident in 2012.

What is slurry?

The Department for Environment Food and Rural Affairs (DEFRA) uses the following definitions in relation to slurry:

  • Slurry – excreta produced by livestock (other than poultry) while in a yard or building (including any bedding, rainwater and washings mixed with it) that has a consistency that allows it to be pumped or discharged by gravity. The liquid part of separated slurry is also defined as slurry.
  • Dirty water – lightly-contaminated run-off from lightly fouled concrete yards or from the dairy/parlour that is collected separately from slurry. (Although Defra guidance allows dirty water to be managed differently from slurry, in legal terms it is still defined as slurry).
  •  Farm yard manure (FYM) – livestock excreta that is mixed with straw bedding material, which can be stacked in a freestanding heap without slumping or free drainage.

What are the benefits of slurry?

Slurry is rich in nitrogen, which helps in the growth of crops. By spreading slurry on your land, you’re helping your soil and reducing the need for costly fertilisers.  What’s more, if you choose a spreading method that results in less ammonia being released into the atmosphere you’ll probably put yourself ahead of potential new legislation. David Ball of the Agriculture and Horticulture Development Board (AHDB) believes that the government will soon be targeting agriculture to reduce their ammonia emissions. And while 80 percent of emissions comes from livestock themselves, the remainder is from fertiliser spreading. A method (like the shallow injection method of slurry) that results in less ammonia in the atmosphere also means more nitrogen in the soil, so everyone is a winner.

Where and how can I store slurry?

Due to the specified spreading season for slurry, Defra say you would normally need capacity to store around 4 months’ worth of slurry, but if you’re in an area with more rainfall then you might need more storage space. All stores need to be impermeable and meet anti-corrosion standards and if you’re building any storage less than 10 metres from inland or coastal waters you’ll need written agreement from the Environment Agency. Don’t forget that run-off from solid manure stores, woodchip, or straw-bedded corals or stand-off pads counts as slurry too.

When can I spread slurry?

With more than 50% of farms within a designated NVZ (Nitrate Vulnerable Zone), there are only certain times of the year that you can spread slurry. There are designated closed periods when nitrogen may be lost from the lands if they’re spread. According to Cross Compliance Solutions (CXCS) the 2018 closed periods are as follows:


Start date End date Land use Soil Type
1st August 31st December Tillage land Shallow/sandy
1st September 31st December Grassland Shallow/sandy
16th September 31st September Tillage land* Shallow/sandy
1st October 31st January Tillage land All other soils
15th October 31st January Grassland All other soils


*For tillage land with crops sown on or before 15th September

What are the risks and how can they be minimised? 

The risks associated with slurry include:

  • Stirring – when slurry is stirred the gasses it gives off can be potentially fatal so the HSE advises you:
    • Mix on a windy day
    • Open all doors and windows in buildings where slurry is stored
    • Keep children away
    • Take animals out of the building
    • Ensure two people are present if possible
    • Use outside mixing points, not over slats
    • Start stirring, vacate the area as soon as possible, then stay away for 30 minutes; stop the stirrer, then stay away for at least 30 minutes
  • Storing – make sure your storage containers adhere to Defra guidelines and that you have plenty of warning signs around any pits. Ideally create barriers around the pits to avoid animals or humans falling in.
  • Transporting – never get into tanks to remove blockages and be careful around transport vehicles. Don’t stand close to the exhaust of a slurry transporter.

Polluter pays

As well as risk to life, there are significant risks to the environment if slurry escapes into waterways. And because legislation is based on a ‘polluter pays’ policy, you are liable for any clean up costs, even if someone else emptied your slurry tank.

This is a growing issue with the Environment Agency in England recording 536 of the most severe cases between 2010 and 2016. Of all instances, the majority of which involved slurry leaks or spills on dairy farms.

In January 2018 a Devon farmer was ordered to pay £9,500 for polluting a watercourse due to a leaky silage clamp. While the amount is significant, it is well below the maximum penalty of £50,000 that could be imposed on any farm found guilty of a breach.

What’s the role of insurance?

Your farm insurance will play a crucial role in minimising the financial damage associated with slurry-related accidents. Many farm combined insurance policies have the option to include the following covers:

  • Environmental impairment liability insurance – this gives you cover for Environmental Agency clean-up costs, damages, the cost of defending your claim and claims arising from environmental impairment.
  • Employer liability insurance – if you employ workers on your farm this will cover you for the costs of any claims they may make because of illness or injury at work.
  • Public liability insurance – cover for you if any member of the public is injured. While it’s unlikely you’ll be inviting members of the public to come and admire your slurry pit, they could pose a risk to someone who inadvertently wanders too close.

You may also want to think about getting cover for personal injury in case you’re injured in a slurry related incident and cannot work. This can be covered under the personal accident section of your farm combined insurance.

Because you’re working with it each day it could be easy to become complacent about slurry and forget the risks it can pose. But by adopting best practice and spreading the word (as well as the muck!) in the farming community you can help make slurry-related deaths and pollution incidents a thing of the past.