Ireland's Environmental Protection Agency (EPA) this week threatened to prosecute Galway City Council after nearly 200 people were diagnosed with cryptosporidium poisoning.
The council is responsible for providing drinking water to people across the west coast county of Galway. The first cases of cryptosporidium were diagnosed in mid-March, forcing thousands of people to boil their water before drinking it.Just last month the EPA gained powers to prosecute suppliers that provide water that is unfit for human consumption or that allow pollutants to degrade river water quality. A spokeswoman said that it 'reserved the right' to take action against Galway City Council.Cryptosporidium is a bacterial disease that causes diarrhoea and vomiting. The organism lives in human or animal hosts and lays eggs called oocysts, which the host excretes. Oocysts can survive for long periods in water until they are ingested by a new host where they hatch and repeat the cycle.The outbreak has been blamed on heavy rainfall during January and February that led to sewage and livestock slurry being discharged into the River Clare, the source of most of the county's raw water.According to the EPA, an old treatment plant at Terrylands has been identified as the principal route by which the cryptosporidium entered the water supplies. Galway City Council plans to take the Terrylands plant out of service in early summer. It claims it cannot shut the plant down sooner because it needs to put extra treatment capacity in place at another plant to prevent a supply shortfall. The Terrylands plant will be upgraded with improved filtration systems.In a statement Galway City Council defended its past performance: 'Since 1999, monthly [monitoring] results for cryptosporidium indicate that at no time, prior to the current outbreak, did the levels exceed the UK guideline value [of one egg per 10l of treated water]'.