Contract awarded to provide additional capacity and higher levels of treatment at Ringsend

Uisce Éireann has announced a significant milestone in Ringsend Wastewater Treatment Upgrade Project with the award of the first of four contracts to upgrade the existing treatment tanks to provide additional capacity and higher levels of treatment. This is a key step in bringing the plant into compliance, safeguarding the environment and facilitating housing and commercial development.

The award of the contract to CAW-TES-Farrans Consortium marks the start of the next major element of the project, which will introduce a new technology to allow a greater volume of wastewater to be treated to a higher standard. Works on the construction of a new 400,000 population equivalent extension at the Ringsend Wastewater Treatment Plant commenced in 2018 and is due to be completed in the first half of 2021. 

This is the first of four contracts to retrofit the secondary treatment tanks at the plant with Aerobic Granular Sludge (AGS) Technology. The works are being carried out on a phased basis to ensure that, as far as possible, the plant can continue to treat wastewater from the Greater Dublin Area at current treatment levels throughout the upgrade. Works under the first Retrofit contract are anticipated to take 12 months and are due to start in the coming weeks. The second contract is at procurement stage and is anticipated to commence in early Q3 2021.

The Ringsend Wastewater Treatment Plant, which treats approximately 40% of Ireland's public wastewater, is currently overloaded and is not in compliance with the EU's Urban Wastewater Treatment Directive.

Jean Hobbs, Project Manager with Uisce Éireann, said: "Having adequate wastewater treatment infrastructure is essential to safeguard the environment and to facilitate housing and commercial development. These works will allow the wastewater generated every day in our homes, schools and workplaces to be treated in compliance with the EU and national wastewater treatment regulations and returned safely to Dublin Bay."

The Ringsend Upgrade Project is a critical element of a range of major investments that Uisce Éireann is rolling out to support housing and economic projections for growth for the Greater Dublin Area, safeguarding the environment and protecting public health. The project will upgrade and expand the capacity of Ringsend Wastewater Treatment Plant to increase, on a phased basis, the capacity to treat the wastewater for a population equivalent of 2.4 million while achieving the standards of the Urban Wastewater Treatment Directive. 

There are four key elements to the upgrade project:

1. Provision of additional secondary treatment capacity with nutrient reduction (400,000 population equivalent) due for completion in the first half of 2021;
2. Upgrade of the 24 existing secondary treatment tanks to provide additional capacity and nutrient reduction, which is essential to protect the nutrient-sensitive Dublin Bay area;
3. Provision of a new phosphorous recovery process; and
4. Expansion of the plant's sludge treatment facilities.

In February 2018, the work commenced on the first element, the construction of a new 400,000 population equivalent extension at the Ringsend Wastewater Treatment Plant.  These works are at an advanced stage with testing and commissioning stages expected to be completed in the first half of 2021. 

Wastewater from Dublin has been treated in Ringsend since 1906. Built in 2005, the current plant is the largest in Ireland and was designed to cater for an equivalent of 1.64 million people.  The plant is operating over capacity; the average daily load received at Ringsend Wastewater Treatment Plant in 2019 was 1.98 million population equivalent with peaks well in excess of this. The plant serves the Greater Dublin Area, with networks stretching from the city centre to suburban areas such as Dalkey, Rathcoole, Clondalkin, Blanchardstown/Mulhuddart, Dublin Airport and Howth, and parts of Meath such as Dunboyne, Clonee and Ashbourne.