Irish Water is defending its repair and remediation programme.
It says it has been carrying out major works to eradicate e-coli from supplies.
And it is working to address Cryptosporidium outbreaks.
The EPA is planning to prosecute Irish Water if it fails to tackle supply issues within targeted time frames.
The utility’s Jerry Grant says the EPA began its Remedial Action List before they’d tackled the e-coli problem: