There are now just 20 “pristine” river sites around the country, down from more than 500 in the late 1980s, according to a report from the Environmental Protection Agency (EPA).
Agricultural runoff and wastewater are among the factors contributing to the decline in water quality, according to the EPA.
Just 53% of surface water bodies have satisfactory water quality. The Water Quality in Ireland Report for 2013 to 2018 shows that the number of seriously polluted river-water bodies has increased from six to nine. It comes after several years of an improving trend.
The key findings include:
EPA director Matt Crowe said water qualities are worsening despite some positive trends.
“The findings of this report indicate that water quality is getting worse after a period of relative stability and improvement,” he said.
“We now have an increase in the number of the most polluted river sites, and the number of rivers in poor ecological health is also increasing. Positive trends reported previously by the EPA have reversed.
Not only are we failing to improve overall water quality, we are also failing to prevent further deterioration of our rivers.
The main significant pressures impacting water quality in Ireland include agriculture, wastewater discharges, impacts to the physical habitat conditions including excess sediment, and pressures from forestry activities.
Of particular concern in the most recent assessment is the increase in nutrients — nitrogen and phosphorus — finding their way into water bodies. Agriculture and wastewater are the main sources of these nutrients. More than a quarter of river sites monitored have rising nutrient levels and nutrient loads to the marine environment have also increased.
Water programme manager Mary Gurrie said the increase in nutrient concentrations is a “worrying development”.
“These excess nutrients come from human activities, predominantly our farms and wastewater,” she said.
“We need to address the sources and the pathways by which these nutrients make their way into our rivers and lakes. Good water quality is essential for our health and wellbeing.
“The National River Basin Management Plan sets out a programme of measures to protect and improve water quality. It is essential that the measures required are implemented to avoid further deterioration and achieve the good water quality which people expect,” she said.