National Inspection Plan

A regime for inspecting domestic wastewater treatment systems (or better known as septic tanks) was established in Ireland in 2013. The Environmental Protection Agency is responsible for the development of the national inspection plan for domestic waste water treatment systems. The plan outlines the risk based methodology used to select sites for inspection.

The EPA has published the third National Inspection Plan 2018-2021: Domestic Waste Water Treatment Systems  following a period of public consultation.  The plan covers the four year period from 2018 to 2021.  Each submission received was reviewed and a response to the main issues raised can be found in the NIP Public Consultation Response Document.

The European Court of Justice found that Ireland had not met the legal obligation required by the 1975 Waste Framework Directive to regulate the waste water generated in our unsewered areas.  This National Inspection Plan for Domestic Waste Water Treatment Systems responds to Ireland's failure to implement the 1975 Waste Directive.

The aim of the plan is to protect human health and water quality from the risks posed by domestic waste water treatment systems. To achieve this a two-strand approach of education and awareness strategies has been developed linked with a risk-based inspection process.


The plan is delivered by local authorities and the number of inspections for each county is allocated on a risk basis. 'Risk-based' means putting resources where the risks are greatest to human health and the environment. The plan focuses particularly on areas where the potential risk to public health and valuable water resources is higher.

The regulations ( S.I. No. 223 of 2012) governing the operation and maintenance of domestic wastewater treatment systems (DWWTSs) require owners of DWWTS to operate and maintain their systems and this includes de-sludging. All domestic wastewater treatment systems require ongoing maintenance to ensure that the septic tank/treatment system operates effectively and that solids do not enter the percolation area and clog the distribution pipe work.

The inspections allow for the systematic collection of information on the condition of domestic waste water treatment systems in Ireland. The results show that many of the failures could have been prevented.

The EPA also publishes the results of the findings of the inspection process on an annual basis in a series of reports known as implementation reports.

The most recent implementation report is for 2019.