Austria, Cyprus, Greece and Malta are home to Europe's cleanest bathing waters, the European Union's environment watchdog said Thursday.
The four countries scored "excellent" ratings for at least 95 per cent of their bathing waters, the European Commission and the Copenhagen-based European Environment Agency (EEA) reported.
In Cyprus, 99.1 per cent of all bathing sites recorded the highest quality level.
Water quality was tested in over 22,000 beach, river and lake sites across Europe during 2018 in the 28 EU members as well as non-EU members Switzerland and Albania.
Across the 28 EU countries surveyed, 85 per cent of bathing sites achieved excellent status - a slight increase compared to 2017.
Inproved wastewater treatment during the past four decades was cited as a factor by Hans Bruyninckx, EEA chief.
Other challenges remained, ranging from "tackling plastic pollution to protecting marine life," he said.
The tests from the 30 countries showed that about 1.3 per cent of bathing waters - a total of 301 - were rated as having poor water quality, posing a risk of illness such as diarrhoea, a slight drop compared to 2017.
Pollution from sewage or waste from livestock were the main sources of poor water quality. Floods or heavy rains can result in more pollution being washed into rivers, lakes and seas, the report said.
The countries with the highest number of bathing waters failing to meet EU standards in 2018 were Italy (89), France (54), and Spain (50).
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