Irish Water is being held to legally binding directives to improve local water supplies.
Over 8,000 people in Cavan were affected water restrictions last year.
The failure in the supply in Bailieborough was the main cause.
Increased manganese in Bailieborough left 7,785 people with a “Do Not Consume” notice last December.
301 people in Swanlinbar had a notice for most of July because of elevated chlorine.
The environmental watchdog carried out two audits in Cavan in 2019.
The EPA issued directives to Irish Water for failing to meet required standards on three supplies in the county.
No restrictions or directions were put in place for public water supplies in Monaghan last year.
Speaking to Northern Sound, Dr Michelle Minihan from the EPA said they can hold the utility to account for failures.
