Environment
and Planning
Irish developments
COMMENCEMENT OF REMAINING PLANNING AND DEVELOPMENT ACT 2024 PROVISIONS DEFERRED
The Department of Housing, Local Government and Heritage announced on 9 October 2026 that commencement of the remaining provisions of the Planning and Development Act 2024 had been deferred. Part 4, relating to development consents (planning permissions etc.), is one of the key parts not yet commenced. The Department stated that a new date will be announced with advance notice. In the meantime, the relevant provisions of the Planning and Development Act 2000 continue to apply.
EU developments
COMMISSION PROPOSES ONE-YEAR DELAY TO METHANE REQUIREMENTS
The European Commission has proposed postponing certain requirements under Regulation (EU) 2024/1787 on methane emissions by one year. The proposal covers monitoring, reporting and verification obligations for fossil-fuel importers, and methane-intensity provisions for importers and EU producers. It follows concerns about securing energy supplies compliant with the Regulation amid disruption to global trade due to conflict at the Persian Gulf. This is draft legislation and will need to proceed through the European Parliament and Council before it is adopted.
CJEU proceedings
EUROPEAN COURT RULES ON SLOTS DISPUTE AT DUBLIN AIRPORT
On 15 October 2026, the Court of Justice of the EU gave judgment in the case of daa and others (C‑857/24). The case concerns Dublin Airport’s 32 million passengers per annum (32mppa) cap and its effect on the number of “slots” available for aircraft movements at Dublin Airport. The CJEU held that binding planning conditions limiting annual passenger numbers may constitute relevant technical, operational or environmental constraints in the determination of the parameters for allocating slots. The Court further ruled that resulting parameters for slot allocation may result in some series of slots or components thereof not being allocated to air carriers which would in principle be entitled to them. This may prevent renewal of historic slots otherwise eligible for reallocation.
The Court summarised its decision, stating that:
“... during slot allocation, account must be taken of constraints such as the 32mppa condition and … such constraints may have the consequence that some series of slots can no longer be allocated”.
UNLAWFUL TO RULE OUT THE NEED FOR HABITATS DIRECTIVE ASSESSMENT BASED ON SIZE THRESHOLD ALONE
In case C-548/25 Dryade, the CJEU held that the Habitats Directive disallows national legislation which exempts certain categories of plans or projects from the obligation to carry out an appropriate assessment (“AA”) on the basis of predetermined criteria and thresholds where those criteria and thresholds do not make it possible to rule out with certainty, on the basis of objective information, that those plans or projects may have significant effects on a special area of conservation, individually or in combination with other plans or projects. This arose in the context of a water abstraction proposal which did not require a permit or AA under Belgian law, owing to its small size.
The CJEU reiterated that the mere fact that a use involves only small quantities of water does not in itself make it possible to rule out that some such uses may have a significant effect on a protected site. Even assuming that such water uses have no significant effect on the status of a body of water, it does not follow that they cannot have a significant impact on nearby protected sites.
Irish judgments
ABSENCE OF SITE-SPECIFIC CONSERVATION OBJECTIVES INFORMING AA SCREENING / APPROPRIATE ASSESSMENT DOES NOT MEAN PLANNING PERMISSION MUST BE QUASHED
In our August update, we covered the CJEU judgment in the joined cases of Knocknamona (C-27/25) and Massey (C-356/25) on 16 July 2026. The judgment was about whether site-specific conservation objectives (“SSCOs”) are a precondition to a valid Appropriate Assessment (“AA”) or AA Screening under the Habitats Directive. The Court held that SSCOs are a necessary prerequisite to a valid AA or AA screening. For AA screening, it may be possible to identify the geographical area likely to be affected by a plan or project based on geographical factors, for example where distance from a protected site or the absence of a plausible impact pathway can be shown. However, AA screening concerning a protected site within the Zone of Influence cannot be carried out without taking account of the conservation objectives specific to that site.
In three recent judgments of the Irish High Court, this EU judgment has been considered. In Wild Ireland Defence CLG v An Coimisiún Pleanála (No. 2) [2026] IEHC 652 (PDF 530 KB), Save the South Leinster Way v An Coimisiún Pleanála [2026] IEHC 654 (PDF 583 KB) and Massey v An Coimisiún Pleanála (No. 6) [2026] IEHC 656 (PDF 258 KB), Humphreys J refused to quash the planning permissions which had been challenged. In each case, the expert evidence put forward by the developers showed that the legal defect in the assessments arising from the absence of SSCOs would not have made a difference to the outcomes of the assessments. Humphreys J reiterated that a legal error will not automatically give rise to a quashing of a planning permission.
COURT REFUSES APPEAL OVER KILKEE WASTEWATER TREATMENT PERMISSION
In Busher v An Coimisiún Pleanála (No. 3) (PDF 236 KB) [2026] IEHC 653, Humphreys J refused permission to appeal his first-instance judgment in which he refused to strike down planning permission for a pumping station and wastewater treatment plant at Kilkee, County Clare.
Two questions were proposed for an appeal:
- “Are applicants entitled to raise an issue relating to interpretation of legislation in judicial review if they have not, in their submission, addressed the applicable legislation, but have confined themselves to saying that there are substantive issues (which the legislation addresses) which need to be addressed?”
- “Is a condition that requires a developer to build in accordance with plans and particulars which includes a commitment to comply with R3 of the 2005 Regulations sufficient to comply with R6 of those regulations?”
The Court held that the first question did not arise from the case, because the applicants were not restricted from raising an issue relating to interpretation of legislation. The second question was not a point of law, but a question of the application of law to the facts at hand. These were the main reasons given for refusing leave, but the court also noted:
“An appeal is not in the public interest, primarily due to the urgent need for wastewater treatment in Kilkee and the unacceptable ongoing discharge of untreated wastewater directly into the sea.”
COURT UPHOLDS REMEDIATION ORDERS FOR UNAUTHORISED WASTE INFILLING
In Cork County Council v Collins [2026] IECA 196 (PDF 266 KB), the Court of Appeal dismissed an appeal against orders made, pursuant to a “staged approach”, requiring removal of infill and restoration of land, within a Special Area of Conservation, reclaimed for equestrian use. Construction and demolition waste had been deposited on the land, and the appellant had previously pleaded guilty to causing environmental pollution in related proceedings. In the High Court, Phelan J had ordered that the first step in remediation should be the acquisition of all necessary permissions and consents, and the carrying out of all requisite environmental assessments.
Meenan J found sufficient evidence of environmental damage to support the remediation orders under sections 57 and 58 of the Waste Management Act 1996, and no basis to disturb the High Court’s findings. The Court found that the appellant landowner had mischaracterised the High Court’s orders and rejected the appellant’s interpretation of the waste-licensing requirements.
COURT DISMISSES CHALLENGE TO LITTLE ISLAND WASTE FACILITY PERMISSION
In Little Island Community Association CLG v An Coimisiún Pleanála [2026] IEHC 679 (PDF 650 KB), Humphreys J dismissed a challenge to permission for a waste facility. The grounds of challenge ultimately relied on by the applicant community association were misinterpretation of the Cork County Development Plan, failure to prevent disturbance of protected species, and inadequate EIA.
The Court rejected the applicant’s interpretation of the development plan as being an impermissible merits-based challenge to the Commission’s decision, found there was insufficient evidence and insufficient pleadings to support the protected-species claim, and held that the EIA claim was based on an incorrect interpretation and unfair reading of the environmental assessment reports which could, contrary to the applicant’s claims, be read consistently.
COURT REJECTS FURTHER CHALLENGE TO WIND FARM TURBINE PLANS
In North Westmeath Turbine Action Group v An Coimisiún Pleanála (No. 3) [2026] IEHC 505, Quinn J rejected a further attempt to challenge planning permission for a 13-turbine wind farm near Coole, County Westmeath, being developed by Statkraft. This further judgment arose from an attempt by the applicant to raise an issue regarding design flexibility, relying on the case of Sweetman 17. Quinn J found that on the facts, Sweetman 17 could be distinguished because there was “no room for open-ended deviation from the illustrated dimensions” in the drawings submitted. Several other reasons were cited in refusing to quash the permission, including that there was no evidence of prejudice to others.
In summary, the Court held:
“The harm suggested is that turbines might be erected which are smaller in dimensions than those described and illustrated. I accept the notice party’s evidence that it did not interpret the decision as permitting such deviations as the applicant describes. Critically, this is consistent with the applicant’s own interpretation that the developer was proposing turbines having a tip height of 175m. There was therefore no irrationality in the decision of the respondent.”
APPEALS MUST ARISE FROM MATTERS PLEADED
In Kimmage Dublin Residents Alliance CLG v An Coimisiún Pleanála (No. 2) [2026] IEHC 677 (PDF 340 KB), Humphreys J refused leave to appeal his decision refusing to strike down a planning permission for a residential development. The proposed questions concerned departures from development plans, the effect of strategic environmental assessment on departures from those plans and the implementation of EU Directives in national law. The Court held that the questions did not arise from matters actually pleaded in the case, and leave was refused primarily for that reason.
SUPREME COURT REFUSES APPEAL IN ENNIS DATA CENTRE CLIMATE CHALLENGE
In Doyle v An Coimisiún Pleanála [2026] IESCDET 123, the Supreme Court refused permission to appeal the High Court decision upholding permission for a data centre and related substation in Ennis, County Clare. The challenge concerned climate duties under section 15 of the Climate Action and Low Carbon Development Act 2015.
The Court found that two questions in respect of which leave to appeal was sought had not been properly pleaded at the outset of the High Court proceedings. These related to the efficacy of CPPAs as mitigation measures, and whether and how carbon budgets and sectoral emissions ceilings must be addressed within a section 15(1) consistency analysis. A third question, regarding principles of interpretation for an administrative decision, was not accepted because there was no doubt as to the law to be applied and no matter of general public importance arose.
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