While the review recognises “positive investment and efforts from farmers” since the NAP process began in 2007, it says “further, significant change” is needed.
It added that the agri-food industry has “become heavily dependent” on millions of tonnes of imported animal feed and fertiliser that can provide more nutrient that animals and crops need.
That leads to agricultural run-off which contributes to water pollution, damage to sensitive habitats, and blue-green algal blooms in Lough Neagh and elsewhere.
The OEP has made 12 recommendations to help strengthen the regulations, looking at compliance, technical provisions, and establishing the scale of nutrient pollution reduction required to improve water quality.
They include providing advice and support to farmers, increasing inspections of farms, and future-proofing the regulations for increasing climate change.
The report warns that the deterrent effect of fines for pollution incidents may be relatively limited, but that both civil and criminal sanctions should remain available to regulators in accordance with the scale of each case.