OVER HALF OF septic tanks tested by the Environmental Protection Agency (EPA) last year failed, and some councils are way behind on inspections.

This is despite grant schemes for remediation increasing in 2024 from €5,000 to €12,000.

Of the 1,466 septic tanks inspected in 2025, some 59% (863) were not built or maintained properly.

This is a “worrying” statistic, said EPA programme manager Noel Byrne, who warned some families could be risking their health “without realising it”.

Faulty systems can contaminate drinking water wells and expose people to harmful bacteria and viruses. They can also pollute rivers and streams through releases of nutrients such as nitrogen and phosphorus.

By the end of 2025, 84% of all tanks that failed inspection from 2013 to 2025 had been fixed. This is up from 70% at the end of 2018.

Homeowners are told by their council to fix the issue via an advisory notice. The number of notices open for more than two years decreased from 523 at the end of 2024 to 442 at the end of 2025.

The EPA says this has been aided by increased grants, greater enforcement by local authorities, and increased regulatory oversight of the local authorities by the EPA.

Fingal, Donegal and Wexford local authorities did not complete their full 2025 allocations and are required to complete them this year instead, in addition to their 2026 list.

The EPA has issued legal directions to local authorities in the past where inspection shortfalls persisted.

“This option remains open to the EPA if current shortfalls are not addressed,” the agency said.