The High Court has overturned a Bord Pleanála "fast track" strategic housing approval for a 197 residential unit development in Bearna, Co Galway.
Mr Justice Garrett Simons said the board acted outside its powers when it granted permission for the development to Burkeway Homes on an 18 acre site 6.5km from Galway city centre.
The board's decision was challenged by Gabriel McGoldrick and Heather Hill Management Co, the managers of the adjoining Heather Hill residential development. They claimed, among other things, the board did not properly comply with the County Development Plan.
The board opposed them and Burkeway Homes was a notice party.
Mr Justice Simons found the development would involve two material contraventions of the development plan in that it would breach the population allocation for Bearna as set out in the core strategy and settlement hierarchy as recently affirmed by a variation to the plan in July 2018.
Bearna has a population of nearly 2,000 and the strategy envisages an increase of 420 by 2021.
The second contravention was that the development plan requires a "justification test" for development works in an area of the site which has been identified as being at risk of flooding. This was not done and the board erred in law in purporting to defer the completion of a site-specific flood risk assessment, he said.
"The fact - if fact it be - that there is a conflict between two objectives of a development plan does not allow a decision maker to contravene one of the objectives and to dismiss that contravention as immaterial", he said.
The issue of conflicting objectives is provided for in the 2016 Residential Tenancies and Planning and Development (Housing) Act under which "strategic housing development" applications such as these are made directly to the board.
An Bord Pleanála is authorised to grant permission in contravention of a plan where there are conflicting objectives, he said.
The board must however first consider whether the criteria under the 2016 Act have been met, the judge said. The board must also indicate in its decision the "main reasons and considerations" for contravening the plan.
"An Bord Pleanála mistakenly concluded the proposed development did not involve a material contravention and as a consequence did not address its mind to these statutory requirements.
"These legal errors vitiate the decision to grant planning permission".
The judge also found that separately the board failed to carry out a proper screening exercise for the EU Habitats Directive. He found it erred in relying on measures which were intended to avoid/reduce potential harmful effects of the proposed development on two European sites located in Galway Bay.
He set aside the decision and adjourned the matter to next month to hear from the sides on whether it should be sent back for reconsideration by the board and for costs matters.