Dr. Elaine McGoff:

I thank the committee for the invitation to attend. I am Dr. Elaine McGoff. I am the head of advocacy with An Taisce. I am joined by Professor Sweeney and Mr. Lumley.

The starting point for any discussion on nitrates and the nitrates derogation must be an acknowledgement that nitrates from dairy farming are negatively impacting water quality, both surface and groundwater, and that we need a different approach to mitigate that impact. In 2021, the Environmental Protection Agency, EPA, identified several catchments of concern for elevated nitrogen concentrations in the south and south-east, including the River Bandon, River Slaney, River Lee and the River Tolka and River Liffey catchments.

Of these ten catchments, urban wastewater was the main nitrate pressure in only one, the Tolka-Liffey catchment. While tillage can also contribute to nitrate loss, data has shown that even in some of the most tillage-heavy catchments, such as the Barrow and Slaney catchments, only 28% and 27% respectively of the nitrate was attributable to arable farming. Most nitrogen in identified problem catchments for nitrate came from pasture-based agriculture.

Where is the nitrogen coming from? There is a clear and well-established link between surplus, unused nitrogen and the nitrate leached to water in free-draining soils. As shown in the chart, figure 2 in my opening submission, the greater the surplus nitrogen, the greater the leaching shown. Therefore, it follows logically that if we want to reduce nitrate leached to water, we need to reduce the surplus nitrogen that drives the pollution.

In figure 3 of my opening submission, members will see that dairy methane and nitrogen excretion rates are strongly, and in some cases almost linearly, related to milk yield per cow. In other words, as milk production goes up, there is a direct increase in nitrates, ammonia and methane emissions.

What about existing measures to prevent nitrogen leaching? A fundamental point which needs to be well understood by anyone working in this area is that not all water quality measures are effective for all pollutants. In an Irish context, the main pollutants from agriculture to water are phosphorus, nitrogen and sediment. There can be a tendency to assume that measures designed to mitigate other pollutants, such as phosphorus, sediment or ammonia are equally effective at addressing nitrate. This is frequently not the case. For example, if landowners in one of the catchments of concern for nitrate wanted to mitigate the nitrate run-off from their farms, they might rely on the use of low emission slurry spreading, LESS, protected urea or extended buffer zones. These measures, while valid and useful for phosphorus, ammonia and sediment mitigation, are not particularly effective for reducing nitrate loss. They would not be a good use of time or resources, if the main aim was to address nitrate losses to water. This is well illustrated in table 1 in my submission, which I took from the Waters of LIFE project, which assessed the efficacy of different agricultural measures for nitrates. Of note in this table is that the only highly ranked measure for nitrate mitigation is reducing the nitrate load, for example through a reduction in livestock units per hectare. To emphasise this point, Teagasc modelling also demonstrated that urine patches from cattle at pasture can be responsible for as much as 63% of nitrate leached. Only 29% of the nitrate loss was attributable to artificial fertiliser and just 8% was attributable to slurry. Again, I have provided a graph from Teagasc research, figure 2, which shows that quite clearly.

To put it simply, where nitrate is the pollutant of concern, compliance regarding slurry spreading and storage, while obviously desirable from a broader environmental perspective, will have relatively limited benefits in catchments where we have a serious nitrogen problem. We are all familiar with the phrase "the right measures, in the right place" for water quality protection, but while we have made significant progress on this when it comes to measures for phosphate and sediment, we are still failing to apply the correct measures when it comes to nitrate. Many farmers are willingly putting measures in place on their farms, but frequently they are not measures designed to adequately address nitrate leaching. In many cases we are seeing a nitrate problem with phosphate solutions.

How should we address this? With this science in mind, we need a catchment-based approach, with measures tailored at the catchment scale, based on the in-stream load for that catchment. More dramatic measures will be needed in some catchments than in others. As outlined earlier, nitrate leachate reductions are achieved primarily through reducing the surplus nitrate in a given catchment. Where we have catchments requiring relatively modest nitrate decreases, for example the Suir, the Blackwater and the Lee, the decrease of the derogation limit from 250 to 220 kg N/ha/yr may get us a fair way towards the necessary reduction in the nitrate load. However, where we have catchments with far higher levels of in-stream nitrate load, for example in the Barrow and the Slaney where there is 50% too much nitrogen going into the catchments, we will need far greater nitrogen load reductions, well over and above what will be provided by the drop from 250 to 220 kg N/ha.

Irish farmers, especially derogation farmers currently, are being asked to jump through a growing number of environmental hoops at their own cost. It is imperative that they can be confident that the measures they put in place will actually address the environmental problem at hand. I can tell you that based on the Environmental Protection Agency, EPA, and Teagasc science, I have little confidence that the existing measures will work sufficiently for nitrate. The systemic failure by the State to implement a tailored catchment-based approach, based on the best available science, is setting farmers up to fail and it is also setting water quality up to fail. Farmers, more than anyone, need honesty. Their livelihood is on the line. The truth is, the majority of the existing measures they are putting in place will not be effective for adequately reducing nitrogen and will not reverse the water quality trends we have been seeing in the south and south east. Farmers should be told that from the outset, not sold false promises, because ultimately, the water quality does not lie and the European Commission has already indicated it will take little else into account.