Nitrates directive - do you have enough storage capacity

The Protection of Water Against Agricultural Nitrate Pollution Regulations (NI) 2004 came into operation in October 2004. This requires the Department of the Environment (DOE) and DARD to establish and apply an action programme of measures throughout Northern Ireland. The draft action programme, currently out for consultation, has been designed to reduce or prevent water pollution from agricultural sources, and involves a range of measures including a minimum storage capacity requirement.

From 1st January 2007, slurry storage capacity must be at least 22 weeks (26 weeks for pig and poultry farms).

The first step is to calculate the 22 week storage requirement for the average numbers of livestock on the farm. If you find that additional storage is required, you should evaluate your system and aim to maximise the available capacity of existing slurry tanks.

Heavy soils in many parts of Fermanagh, when coupled with a high rainfall, frequently result in unsuitable spreading conditions, often extending well into March and April. This will vary between farms, depending on soil type and drainage. Consideration should therefore be given to the provision of additional storage capability over and above 22 weeks.

Separate clean & dirty water:  If rain from a 4-bay shed roof enters a slurry tank, it will take up the equivalent slurry capacity of 16 suckler cows. The separation of clean and dirty water therefore requires careful planning, and regular maintenance of guttering and down pipes. Direct all clean water into a sealed storm water system.

Facilities which include open feeding yards, lagoons, open middens and open silage pits, result in the creation of large volumes of dirty water/slurry. For example, a 15 m x 15 m unroofed lagoon will collect rainwater equivalent to the slurry from 24 suckler cows. Similarly, if a four bay open silo was roofed, storage space for 19 suckler cows would be freed up.

Dairy washings, with a  Biochemical Oxygen Demand (BOD) less than 2000 mg/l, is regarded as dirty water when stored separately, and as such is exempt from the proposed closed spreading period. The dairy washings from a 40 cow herd, if stored separately, will free up tank space equivalent to the slurry produced by 14 dairy cows.

The College of Agriculture, Food and Rural Enterprise (CAFRE) are delivering workshops offering guidance on how to calculate your slurry production and storage requirement. If you have submitted a preliminary application form (FNMS 2) to the Farm Nutrient Management Scheme and would like to attend a workshop at a venue near you, telephone 028 9442 6874. Each workshop lasts about two hours.

Contact Countryside Management staff at your local DARD office if you require additional information on managing slurry and dirty water on your farm.