Thomas Byrne (Meath East, Fianna Fail)

I thank the Deputy for raising the issue and appreciate his concerns regarding this process. The water framework directive establishes the general objective that water bodies be restored to at least good ecological status by 2027. It also makes provision that a more realistic objective for water bodies that have been heavily modified may be set. This applies where restoration would not be technically feasible or would be disproportionately costly, among other considerations.

Under the water framework directive, the Department conducted an eight-week consultation on designating heavily modified water bodies, which closed on 23 May 2025. This followed an initial consultation on characterising heavily modified water bodies completed by the Environmental Protection Agency, EPA, in 2022. The EPA determined, on the basis of expert judgment underpinned by new assessment tools, that these water bodies would fail to achieve the target of good ecological status due to changes in their physical condition. This resulted in a list of 466 water bodies requiring further assessment by the Department to determine their eligibility for designation as heavily modified.

These water bodies have undergone significant physical modifications to support various societal benefits, for example, concrete flood protection schemes. As a result, they are no longer in a natural state and cannot achieve the same environmental targets as their natural counterparts. These water bodies have been modified to supply drinking water, provide flood protection, protect towns and villages and create national ports. It also includes those modified as a result of land drainage, which is carried out under the Arterial Drainage Act 1945. Arterial drainage provides flood protection to thousands of residential and commercial properties, in addition to protecting farmlands.

The water action plan 2024 sets out a series of actions to tackle water quality in Ireland. All member states are required to produce such plans in six-year cycles. Action 3.11 of the plan commits to a review of arterial drainage requirements and the underpinning Arterial Drainage Act to inform future land use policy decisions. Until that is complete and irrespective of designation as heavily modified, the OPW has a statutory duty under the Arterial Drainage Act to maintain arterial drainage schemes.

Designation of water bodies as heavily modified acknowledges that there has been a modification for the purposes of a beneficial specified use and that different, more appropriate environmental standards need to be applied. These water bodies will have an alternative target of good ecological potential instead of good ecological status. Official EU guidance on this process outlines that this is not an exemption but is a specific category of water body with its own classification scheme and objective. It is important to note that good ecological potential reflects the best environmental target that the water body is capable of achieving while the modifications to support the specified use are still in place. In itself, the designation does not have an ecological effect but sets a realistic yet stringent standard.

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