Here’s a report from Hawthorn about Shannon water levels; here is a press statement from a political chap on the matter [PDF]; here is a post showing quite how important agriculture is to the Irish economy.
In brief: it isn’t. As Constantin Gurdgiev says:
[…] Irish agriculture is an extension of the welfare state, in so far as most of the value added in it is provided for by the subsidies.
Given that the sector as a whole includes the relatively small number of productive farms, the value of marginal farms may well be negative. Those occupying such land should be encouraged to abandon it and to take up some more productive activity elsewhere; Mongolia seems like a good bet. Activities designed to help the landlords to continue to pretend to be engaged in an economic activity are a waste of resources.