River Water Quality - Phosphates

High phosphate concentrations in rivers can cause nutrient pollution. Concentrations greater than 0.035 mg/l P can cause harm to other plants and animals. Nearly a third (35.8%) of river sites have too much phosphate in them (concentrations greater than 0.035 mg/l) while the remaining two thirds (64.2%) of sites have phosphate concentrations less than 0.035 mg/l and have satisfactory phosphorus nutrient condition. The areas with the highest phosphate concentrations are mainly in north-eastern counties, some parts of the midlands, and in the lower Shannon catchment, while rivers in the west and north-west generally show the lowest concentrations. A recent review of phosphate trends covering 2013-2018 indicates that a quarter of river sites are experiencing increasing phosphate concentrations.  

Average phosphate concentrations of less than 0.025 mg/l P and less than 0.035 mg/l P have been established in Ireland as legally binding environmental quality standards (EQS) to support the achievement of high and good ecological status respectively.

  • <0.025 mg/lP - Meets High EQ
  • S0.025 - 0.035 mg/lP - Meets Good EQS
  • >0.035 mg/lP - Moderate

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Status for Indicator at Amber