In 2016, after the second EU referendum, Farmers Weekly reported:
Hundreds of Welsh farms may still be under threat from tough EU-led environmental regulations, despite the UK’s vote to leave the European Union.
The prospect of a significant expansion of Wales’s nitrate vulnerable zones (NVZs), driven by the EU Commission’s Nitrates Directive, was a reason some farmers voted to leave the EU.
But the Welsh government says it is pressing ahead with what it says is an “important action to address growing water-quality issues arising from diffuse pollution”.
As an update from the Commission explains:Pure, clean water is vital to human health and well-being, as well as to natural ecosystems, so safeguarding water quality is one of the cornerstones of European environmental policy. Because water sources are not restricted within national boundaries, an EUwide approach is crucial to tackling problems of pollution. The 1991 Nitrates Directive is one of the earliest pieces of EU legislation aimed at controlling pollution and improving water quality. While nitrogen is a vital nutrient that helps plants and crops to grow, high concentrations are harmful to people and nature. The agricultural use of nitrates in organic and chemical fertilisers has been a major source of water pollution in Europe.
There is clearly an issue (literally) concerning run-off from farms of organic and inorganic nutrients. The Welsh government itself points to two or three incidents of river pollution per week. However, gross violations seem to be confined to two or three hot-spots, in north Wales, the south-west and the river Wye. In the latter case, intensive poultry-rearing (as opposed to the more headline-grabbing cattle farms) is implicated. Moreover, farming is not the only source of nutrient run-off. So when agriculture minister, Labour's Lesley Griffiths declared the whole of Wales a NVZ, after promising several times that she would not do so during the SARS/Cov2 emergency and abandoning consultation with the farming unions, and after the Senedd last week narrowly failed to overturn the Griffiths' diktat, I am on the farmers' side.
http://aberavonneathlibdems.blogspot.com/2021/03/welsh-lib-dems-call-for-re-think-of.html sets out the official Welsh Lib Dem position.