Now that farmers within zone A are permitted to spread slurry tomorrow, Monday, January 13, farmers may begin looking at their slurry storage requirements for the next closed period.

Slurry storage requirements are always a topic of discussion when it comes to spreading dates, capacity, nitrates, water quality and farming in general.

The reality is, that farmers are most likely going to see an increase in slurry storage requirements as a result of ongoing research to determine if current storage requirements figures are accurate.

The Department of Agriculture, Food and the Marine (DAFM) has requested Teagasc to complete research on whether the current 0.33m³/cow/week requirement for farms is accurate.

The findings of this two-year study so far, show that slurry storage requirements may have to be increased by as much as 20% and by 30% for soiled water storage.

If farmers are thinking of putting in new tanks this spring and into summer, it would be wise to account for this potential increase in requirements.

Currently, there are four geographical zones that require different levels of storage. They are zones with a 16-week; 18-week; 20-week and 22-week requirement.

The amount of slurry storage that is required is based on the following:

0.33m³/week for dairy cow;
0.29m³/week for suckler cows;
0.26m³/week for over two-year-old animals;
0.26m³/week for animals aged 18-26 months;
0.15m³/week for animals aged 6-18 months;
0.08m³/week for animals aged 0-6 months.

The argument is that, although many farms are within the legal compliance requirement, pressure on tanks can be quite significant if weather conditions are not good when the slurry ban is lifted, which may indicate that the current figure being used is no longer accurate.

These regulation frustrate farmers on the ground, as many felt last year, there was no need to have the slurry ban kick in by October 1, rather than October 15, as the weather in many parts of the country was appropriate for spreading.

The Department of Agriculture, Food & the Marine (DAFM) proposes a Nutrient Storage Investment Scheme, which would offer 60% grant aid with a separate Targeted Agriculture Modernisation Scheme (TAMS) 3 funding ceiling of €90,000, available in spring 2025.

The department stated that the opening date for tranche 6 has been updated to January 23, 2025 to facilitate development work on the 60% grant aid rate for nutrient storage investments.

The closing date of tranche 6 will take place on March 7, 2025.

This separate ceiling would allow farmers who have already benefitted from other TAMS 3 schemes to reapply under the new scheme.

If you need 330L/cow/week for slurry storage and you require 20 weeks of storage, it would mean that you would require 6,600L/cow for that period.

For a 100-cow herd, that means that 660,000L or 174,512 gal of storage is required.

If the herd also has 20 weanling heifers and 20 in-calf heifers, they are given a weekly storage requirement of 0.15m³ and 0.26m³ per animal respectively.

This converts to 150L/slurry/week for the weanling heifers and 260L/slurry/week for the in-calf heifers.

This means 60,000L of slurry storage or 15,850gal would be required for the weanling heifers for the 20-week-period and 104,000L or 27,474 gal would be required for the in-calf heifers.

If that storage requirement for a cow were to increase by 20% or 9.6L/cow/day as a result of research, that would mean the same farm would have to increase its storage capacity by 132,000L or 34,870 gal.

For both groups of heifers, the storage requirement would increase by 32,800L or 8,665 gal.

This means that the total storage requirement for this farm would increase by 164,800L or 43,535 gal.

It is not written in stone that slurry storage requirements will increase by 20%, as it could be more or less, but if thinking of putting in a new tank in the near future, planning for an extra 20% is advisable.

These figures are also based on tanks that are well kept and don't have effluent and rainwater entering into them, which is an issue on some farms affecting their capacity to hold slurry.