More than half of septic tanks failed inspections in 2024

In all, 56% of septic tanks failed their inspections, and the EPA said it is critically important that households maintain their septic tanks given the risks from such failures.

Over half of septic tank inspections by local authorities failed last year, with a “significant number” identified as a risk to human health and the environment, the Environmental Protection Agency (EPA) has said.

In 2024, 1,390 inspections were completed by councils around the country, with the areas chosen at greatest risk of pollution, the majority near rivers known to be at risk from domestic wastewater treatment systems.

In all, 56% of septic tanks failed their inspections, and the EPA said it is critically important that households maintain their septic tanks given the risks from such failures.

“Householders’ water supplies and local rivers may be exposed to contamination from faulty septic tanks, which can pose a serious health risk to individuals and the local environment,” EPA programme manager Noel Byrne said.

“By maintaining their septic tank and fixing any problems identified, householders will protect their health and the environment. Householders should take advantage of the enhanced grants where applicable.” 

According to the environmental watchdog, there are nearly half a million domestic wastewater treatment systems in Ireland used by households to treat sewage. Most of them are septic tanks.

Under its national inspection plan, the EPA obliges local authorities to complete a minimum of 1,200 inspections annually. As well as near rivers, they must also focus on areas where septic tanks are co-located with household drinking water wells.

Of the 1,390 inspections last year, 773 failed because they were not built or maintained properly.

If the inspection fails, householders are told by local authorities to fix the issue. Households can avail of a grant of up to €12,000, increased recently from €5,000, to remediate their septic tanks. There were 265 grants awarded last year, up from 194 in 2023.

Of the septic tanks that failed between the years 2013 and 2024, the EPA said that 82% had been fixed. This was up from 75% at the end of 2021.

However, the EPA said that there are significant differences across local authorities and enforcement remains inconsistent.

It said: “The number of legal cases since inspections commenced in 2013 increased from 62 at the end of 2023 to 66 at the end 2024, however, 95% of those cases were taken by four local authorities, Wexford, Kerry, Mayo and Limerick.

“Local authorities need to increase enforcement, including prosecution where warranted.” 

Cork City is the worst-performing council in terms of the proportion of failed inspections where the issue had been fixed — at 50% — but it had an extremely low number of failed inspections at just eight between 2013 and 2024.

In comparison, 84% of the 587 failed inspections in Cork County had been fixed by the end of 2024.

Dr Micheál Lehane, the Director of the EPA’s Office of Radiation Protection and Environmental Monitoring, said the number of unresolved issues remains “unacceptably high,” which allows risks to public health to continue.

“Greater and sustained enforcement effort is needed by local authorities during their annual septic tank inspections, checking that faulty septic tanks are fixed and taking legal action where necessary,” he said.