A proposed €500m waste water treatment plant at Clonshaugh received planning approval "without any meaningful assessment of what comes out at the end of the pipe", the High Court has heard.
Oisin Collins SC made the claim yesterday when opening proceedings by customs and taxation consultant Sabrina Joyce-Kemper, one of a number of local residents objecting to the development intended by Irish Water to supplement the Ringsend Wastewater Treatment Plant.
Ms Joyce-Kemper, of Portmarnock Crescent, Portmarnock, is objecting to An Bord Pleanala's November 2019 permission for the Greater Dublin Drainage Project.
It comprises a wastewater treatment plant, sludge hub centre, orbital sewer, outfall pipeline and regional biosolids storage facility on a site of around 30 hectares in the townlands of Clonshaugh, Dubber and Newtown.
The "telescoped" hearing, which takes place via video link before Mr Justice Senan Allen, involves an application for permission for judicial review and the review itself.
Listed for 10 days, the case is against the board and the State, with Irish Water a notice party.
Among various claims, it is contended that the planning approval was given contrary to the requirements of two European Directives, the Environmental Impact Assessment Directive and Habitats Directive, lacked sufficient reasons and was contrary to fair procedures.
The board denies the claims, and it and Irish Water argue that Ms Joyce-Kemper has limited legal standing, confining her to raising issues which she had raised during the public consultation process concerning the development.
Irish Water sought the development to cater for future population growth and because the Ringsend plant is operating at over-capacity, resulting in discharges of partially-treated sewage into Dublin Bay.
The plan involves 13km of underground orbital sewer from Blanchardstown to the Clonshaugh plant and a 12km outfall pipeline to bring the treated wastewater to Baldoyle and out to sea.
Ms Joyce-Kemper and other objectors are concerned the outfall pipeline discharges into the Rockabill to Dalkey Island Special Area of Conservation, within 1km of the Ireland's Eye Special Area of Conservation.
The planning application was preceded by a pre-application consultation process that began in October 2012 and continued for five years.
Ms Joyce-Kemper said that, for much of the process, Irish Water proposed to construct a larger plant in two consecutive planning application processes.
Towards the later stages of the consultation, Irish Water said it would build the treatment plant in a single phase to treat a population equivalent to 500,000 people rather than the 800,000 originally envisaged, she said.
A daily sea swimmer, Ms Joyce-Kemper's particular concern was about the impact on water quality in Portmarnock.