More than €110,000 in taxpayer funds went down the drain after a courthouse water leak went undetected for over two years.
An internal audit said the Courts Service had faced excess water charges of nearly €2,900 per month, although the OPW has since carried out repairs.
The Courts Service said the sky-high costs were caused by "a significant unseen water leak" and "pipe defects" in a very old building with antiquated plumbing.
Bills for water at the Chancery Street Courthouse in Dublin – which also houses a childcare court office – shot up from €479 a month to €2,894.
The report said: "The receipt of the November 2023 invoice for €66,202 … appears to have been the first indication that there was a potential problem with the water supply.
"Subsequent bills received also indicated unusually high water usage throughout 2024."
The audit also detailed how the excess water charges may have been missed because they were "miscoded" as fuel oil.
"[This] may partially explain why the increase in water charges was not queried as part of expenditure reviews and analysis," it said.
A spokesman said that following repairs, water charges for the first half of 2025 had returned to normal levels.
He said: "Additionally, steps have been taken to strengthen internal monitoring, coding accuracy, and oversight of utility billing so that any anomalies can be detected and escalated at an earlier stage."
The report also detailed how the Courts Service was owed more than €70,000 in utility bills from the Bar Council, the representative body for barristers, which they had failed to pursue for over two years.
The audit said: "While the Bar Council are aware of arrears in recoupment, delays in recouping sums due may make it increasingly difficult to recover sums especially when the sums due are large."
Other findings from the report included more than €1.15 million spent on expired contracts for electricity and heating fuels.
That left some offices facing "significantly higher tariff rates" when they were supposed to have switched over to a new provider.
The report said that energy market turmoil and ongoing political uncertainty had led to unpredictability around the cost of energy.
In 2024, the Courts Service spent €4.1 million on utilities, a rise of more than 61 percent on what was spent just three years earlier.
It explained how switches to new energy providers were not fully completed with some offices and courthouses left on older higher tariffs.
The report said almost €300,000 was spent on an expired Electric Ireland contract and more than €486,000 on an expired heating fuel contract.
Auditors said higher water bills at some venues were difficult to explain while others had "abnormally low charges."
It said one possibility was "running of water" in unstaffed offices as a preventative measure for Legionella disease.
The report said only limited assurance could be provided for energy contract management and "no assurance" for the management of water use.
For heating oil, the auditors found that the Courts Service was still working off a contract that had not been renewed since 2021.
It said during that time nearly €487,000 had been paid and that this should have been included as "non-competitive procurement" in official records.
Asked about the report, a Courts Service spokesman added: "The audit makes one key recommendation, that overall responsibility for the management of utilities should be assigned to, and centralised within, a single office.
"This, the audit concludes, is essential to preventing similar issues from arising in the future. As part of our response, we are moving to implement this action within current resources."
Reporting by Ken Foxe
