County councils have inspected an estimated 4,000 rural domestic septic tanks around the country since the current inspection regime began four years ago.

The figure is an estimate because the number of inspections carried out in 2016 by the country’s 29 local authorities is still being centrally collated and totalled by the Environmental Protection Agency (EPA).

But testing is continuing at a rate of about 1,000 per year. The total inspected so far is a small fraction of the 400,000 domestic septic tanks in the country.

However, to make best use of available resources, county councils are targeting inspections at areas where water quality is known to be vulnerable and problems are occurring.

As a result, the rate of failure has been relatively high at approximately 50%. No significant change in this is expected for 2016 or indeed 2017.

Inspections

The graphic shows the number of inspections carried out in 2015, the most recent year for which totals are available. Local authorities were given a target of doing 1,000 inspections.

The counties with the highest targets were Cork, Donegal and Galway, followed by Mayo and Wexford.

In total ,1,097 inspections were carried out. Of these, 608 passed and 489 failed.

All 489 householders that failed were given an advisory notice instructing them to replace or fix their septic tanks.

Eight months later, just over half had carried out this work and their advisory notices were deemed “closed”. The other half had yet to carry out this work. Extension had been granted to 59 householders.

The trends

  • Older units had a higher failure rate.
  • The most commonly identified problem was poor operation and general maintenance
  • Next was inadequate emptying (desludging) ­— again a maintenance issue.
  • Next was discharge to surface water or another type of leak from the system — usually a design or installation issue.
  • Less commonly pinpointed were roof water or surface water entering the system and surface ponding. Again, these are design/installation problems.

    • Grant scheme

    The grant aid scheme for installing new septic tanks continues to operate.

    Individual county councils approve and pay out grant aid to householders and then recoup the funds from the Department of Housing, Planning, Community and Local Government. It compiles national totals.

    Its reports showed that 85 householders were paid grant aid in 2015 and 72 in 2016. By Friday 30 June 2017, it had recouped grant funding to various county councils for 18 applicants.

    However, it expects that local authorities have actually paid out more grants in 2017 but have not yet moved to claim the funding.

    So, the total of grants paid out to date is 175. The average grant amount is just over €3,000 and the total grant aid paid out is €528,720.

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