In a statement on Friday, Uisce Éireann said it had reached an agreement to settle the High Court proceedings prior to the full hearing.

The judicial review challenge was lodged by Wild Ireland Energy CLG, founded by environmental activist Peter Sweetman — known for mounting a number of legal challenges to planning decisions.

Uisce Éireann said it has committed to “some additional measures, to further enhance public confidence in the environmental benefits of the project” as part of the settlement.

Maria O’Dwyer, infrastructure delivery director, said: “Uisce Éireann is delighted to secure an agreement and move forward with this critical project.

“The delivery of the Greater Dublin Drainage project is an essential part of Uisce Éireann’s investment in new wastewater infrastructure in Greater Dublin and will facilitate housing and growth while protecting public health and safeguarding our environment.

“While there are several remaining statutory processes to be completed, construction contractor procurement will commence in February 2026.

“When the contractor procurement process is complete, construction work on the GDD project is expected to be completed over a four-year period.”

Government ministers, who have sought to restrict judicial reviews of planning decisions, have warmly welcomed the conclusion of the proceedings.

Jack Chambers, minister for public expenditure, infrastructure, public sector reform and digitalisation, said: “I welcome this significant development which means the Greater Dublin Drainage scheme can now progress to the remaining stages.

“This is a critical project for the social and economic development of the greater Dublin area and our country as a whole.

“This project will support the delivery of thousands of new homes and the conclusion of this process is good news for families, young people and everyone seeking to secure a home as well as businesses and local communities.”

He continued: “Earlier this week we published the Accelerating Infrastructure taskforce action plan which detailed 30 comprehensive time-bound and high-impact action points to massively scale up and speed up critical infrastructure delivery, with a particular focus on water and wastewater treatment projects like this one.

“Reform of the judicial review system is a specific action point. While access to the courts is vital, it should not be used as a tool to indefinitely delay critical projects that are in the national interest.

“This government will act in the public and national interest so we can build the infrastructure necessary to support our economy, our communities and our people.”

James Browne, minister for housing, local government and heritage, said: “I am very pleased at reports that a settlement that is acceptable to all sides has been reached.

“The GDD project is a critical infrastructure project, not just for Dublin, but also for our national water infrastructure more generally.

“Crucially, today’s outcome is very good news for new homes given the urgent need to accelerate housing supply in North Dublin and its surrounds.

“It is a major step forward in addressing wastewater infrastructure in Dublin, unlocking greater development potential by providing essential increased wastewater treatment capacity.

“Infrastructure is central to meeting the objectives of our new housing action plan — to deliver at least 300,000 new homes — and Uisce Éireann will have our full support as it advances this project.”

He added: “The government remains committed to driving forward the Greater Dublin Drainage project and other key infrastructure projects.

“The wide-ranging reforms recently brought forward by the government will help other major infrastructure projects to progress, and strengthen the foundations for sustainable growth and prosperity for generations to come.”