Dairy farmers, with the exception of winter / liquid milk producers, are obliged to have capacity to store 31 days worth of dairy washings / soiled water from December 1 to December 31, 2024.
Last year, farmers had to have storage for 21 days from December 10 to December 31, however, under Good Agricultural Practices for Protection of Waters Regulations, this spreading ban has been increased by 10 days.
This comes into effect in an effort to reduce the impact of nutrient losses during the riskiest period.
Farmers with winter or liquid milk contracts are not obliged to this regulation for this year, but will have a year to meet the 31-day requirement for December 1, 2025.
The winter milk supplier cannot spread for the last three weeks of the year, as their spreading ban kick on December 10 for the last time, this year.
In 2025, the closed period for spreading soiled water is from December 1 to December 31, for all milk suppliers.
Dairy washings
Dairy washings or soiled water is water that has been collected from the milking parlour, collecting yards, unroofed temporary holding yards, washing beet or machinery, and runoff from silage bases.
Soiled water includes water from concreted areas, hard standing areas, holding areas for livestock, and other farmyard areas where such water is contaminated by contact with any of the following:
- Livestock faeces or urine or silage effluent;
- Chemical fertilisers;
- Washings such as vegetable washings, milking parlour washings or washings from
mushroom houses; - Water used in washing farm equipment;
- If soiled water is stored together with slurry, then as far as the regulations are concerned it is slurry, and is subject to the same rules as slurry.
Within the regulations, soiled water does not include any liquid with a biochemical oxygen demand (BOD) exceeding 2,500mg/L, or a dry matter (DM) content exceeding 1% (10 g/L).
Wash down water which becomes lightly contaminated with livestock faeces/urine in the milking parlour is still considered to be soiled water, according to the Department of Agriculture, Food and the Marine (DAFM).
However, when wash down water enters into the slurry storage tanks, it is still deemed to be slurry and must comply with with slurry storage and spreading regulations.
Usually, the volume of parlour washings produced on farm is 30L/cow/day or 0.21m3/week, or if your collecting yard doesn’t have roof over it, which is the case for many farmers, the storage requirement may be 40L/cow/day.
Farmers should make sure that there soiled water tanks and slurry tanks are completely separated and that all slurry and water are going into the appropriate tanks to get the most out their storage facilities and to save them running tight on space.