Farmers should cut nitrogen use, develop more buffer strips and comply with the Good Agricultural Practice regulations in order to improve water quality, the Environmental Protection Agency (EPA) has suggested.

It said that more targeted agricultural measures are needed in water catchments around the country to reduce the impacts of agriculture on water quality.

The measures are outlined in its report, which concluded that the nitrates derogation should be cut from 250kg organic nitrogen per hectare (N/ha) to 220kg N/ha.

“Measures to reduce nitrogen leaching should be targeted into the nitrate critical sources areas.

“Such measures might include reductions in nitrogen use and increases in nitrogen use efficiency,” it said.

To combat phosphorus losses, it said sediment loss reduction measures should be targeted at “breaking the pathways between the sources and the watercourses in these phosphorus critical source areas”.

Measures here included more buffer strips, farm ponds and the management of ditches. To reduce excess ammonium in water, it said measures to ensure compliance with the Good Agricultural Practice regulations should be targeted.

The EPA has outlined on a map, right, where these measures should take place.

EPA map of where targeted measures should be carried out. \ EPA

Coloured flags indicate areas where agricultural measures are needed to restore water quality.

Orange flags indicate areas to reduce nitrate losses, navy flags are for measures to reduce phosphorus/sediment losses, and red flags indicate that there is a potential farm point source issue.

A white flag indicates areas where agriculture is not identified as a significant pressure and measures to protect existing good water quality are appropriate.

These flags can overlap on the map, for example there may be nitrates and phosphorus problems in the one area.