To ask the Minister of Agriculture, Environment and Rural Affairs for his assessment of the impact that the proposed Nutrient Action Programme will have on water quality at Lough Neagh.

The proposals within the Nutrients Action Programme (NAP) have been based on evidence provided through water quality monitoring data, scientific analysis and academic research.

The evidence clearly demonstrates that there is an overall surplus of phosphorus in the Northern Ireland (NI) agricultural system and that excess phosphorus is a main cause of poor water quality in Lough Neagh and across NI. Source apportionment analysis identifies that agriculture and wastewater treatment are the major sources of excess phosphorus. Therefore, a range of measures, aimed at reducing phosphorus from agricultural sources, is proposed in the NAP consultation.

Surplus phosphorus accumulates in the soils, and from there it is at risk of loss to water. The NAP includes proposed measures to improve nutrient management and reduce the accumulation of phosphorus in the soil. Reducing soil phosphorus levels towards the agronomic optimum (or lower) will deliver reductions in the levels of soluble reactive phosphorus in the associated stream and rivers.

Scientific research demonstrates that a change in the NI Agricultural phosphorus surplus can be seen the following year in our rivers through the measurement of the water quality metric of soluble reactive phosphorus.

It is envisaged that if the proposed NAP measures were implemented, over a five year period, we should see a reduction in the total phosphorus levels in the inflowing rivers to Lough Neagh which would have a positive impact on water quality. This is not the same as the level of the total phosphorus in the Lough water. For the quality of the Lough itself, the accumulated phosphorus in the lake sediment also needs to be factored in. Achieving sufficient reduction in the phosphorus coming from the lake sediment will take many years. However, reducing the phosphorus inputs to the Lough is an essential step in improving water quality.