Ensuring silage effluent facilities are in good condition

Silage effluent is highly polluting and the volume can range from zero to 350 litres per tonne of grass. File Picture.  

Silage effluent is highly polluting, and can cause fish deaths in watercourses, and contaminate wells, if not collected, stored, and spread properly on land.

The volume of effluent can range from zero to 350 litres per tonne of grass.

Now is the time to examine facilities.

• Clean the slab thoroughly (power wash), to check if repairs are needed.

Repairs must be completed to Department of Agriculture, Food and the Marine (DAFM) specifications for Concrete Silage Bases S128 and Resurfacing of Silo Floors S128A (see www.agriculture.gov.ie).

• Store only the amount of silage that the slab or pit is capable of storing safely.

Problems arise if ensiled grass extends onto or over effluent channels.

Effluent must enter channels under the polythene cover.

To prevent effluent flowing over pit walls, do not store silage too high over walls, slope the grass back at 45-degrees from the top of the walls.

• Check the effluent tank during silage making.

Spread effluent on land at a dilution rate of one part silage effluent to one part water or slurry.

Do not spread if rain is forecast in the next 24 hours.

Do not spread:

n Within 5m of any watercourse (or within 10m, where the field slope exceeds 10%);

n 20m from lakes or main rivers;

n 25-200m from a well or public water supply.

• Wilt silage for 24 hours before ensiling, to reduce silage effluent.
• In wet conditions, additional drainage pipes on the pit floor can help get effluent out, relieve pressure, and reduce pit slippage.
• Bailed silage is generally drier, but any effluent must be collected, as with pit silage.