20 November 2024
31 day requirement for soiled water storage to come into effect
Farmers, with the exception of winter/liquid milk producers, are obliged to have capacity to store 31 days’ worth of soiled water from December 1, 2024.
In order to reduce the impact of nutrient losses in the riskiest period, and as legislated for under the Good Agricultural Practice for Protection of Waters (GAP) Regulations, the spreading of soiled water will be prohibited for all dairy farmers, with the exception of winter/liquid milk producers, between December 1 and December 31, 2024.
Farmers supplying liquid or winter milk and who have a contract for same (as per SI No 113 of 2022) will have a further year to meet the 31 day requirement, with the regulation taking effect on these farms on December 1, 2025. These farmers cannot spread soiled water for the last three weeks of 2024.
Tom Fallon, Teagasc Infrastructure Specialist, explains that parlour washings are the main source of dirty water, but it also includes runoff from open silage pits.
“The soiled water storage requirement is for the peak cow numbers milked between October and January and does not relate to the numbers milked during December. Nevertheless, farmers milking cows through December need to provide ample storage to comply with the new closed period,” Fallon said.
Although the volume of parlour washings produced on farms can vary, with factors such as the type of parlour, area cleaned and the volume of the washer all having a role, Fallon added: “The typical volume of parlour washings produced on farms is 30L/cow/day or 0.21m3/week. Rainfall on unroofed collecting and return yards may bring the storage requirement up to about 40L/cow/day.”
The Infrastructure Specialist at Teagasc also noted that it is acceptable to store parlour washings in slurry tanks. However, when this occurs, it has to be treated as slurry and retained for the full slurry spreading closed period.
“Parlour washings are classified as soiled water provided they have a biochemical oxygen demand (BOD) of less than 2,500 and a dry matter content of less than 1%.
“It’s worth noting that if cows are eating silage while standing in the collecting yard, the contents of the tank is regarded as slurry and it has to be stored from the 1st of October until the end of the closed period for spreading slurry,” he added.