Works progress on the Ringsend Wastewater Treatment Plant Upgrade Project

11 March 2021

Irish Water has announced the signing of a contract for the first facility in Ireland to recover phosphorous from wastewater, as part of the Ringsend Wastewater Treatment Plant Upgrade Project.

The upgrade of the Ringsend Wastewater Treatment Plant is essential in order to enable future housing and commercial development and help to ensure that Dublin is able to sustain continued growth in the medium term. The project will deliver, on a phased basis, the capacity to sustainably treat the wastewater for a population equivalent of 2.4 million while achieving the standards of the Urban Wastewater Treatment Directive.

The signing of this contract marks an important milestone in this ongoing Upgrade Project. Phosphorous is a valuable finite resource and this facility will enable it to be recovered and processed for use as a fertilizer in agriculture. The provision of a phosphorus recovery process is a key element of the project strategy to achieve compliance with the Urban Wastewater Treatment Directive.

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 Irish Water, said: “Having adequate wastewater treatment infrastructure is essential to safeguard the environment and to facilitate housing and commercial development. This latest contract is a key part of the Ringsend Wastewater Treatment Plant Upgrade Project and highlights Irish Water’s commitment to sustainability and resource recovery in the treatment of wastewater.

Phosphorous is a finite resource which has real value in agriculture and other sectors, so its recovery in this way will not only help protect the water quality in Dublin Bay, but is also in line with the principles of a circular economy and resource recovery.

The contract for the construction of the Phosphorous-Fixation (P-Fix) Facility has been awarded (following an extensive tendering and evaluation process) to Murphy International Ltd. Construction and is expected to take approximately two years.

The Phosphorous Recovery Facility will be built within the confines of the existing Ringsend Wastewater Treatment Plant. It will operate in tandem with the Aerobic Granular Sludge technology being installed in the wastewater treatment plant, to reduce the levels of phosphorous being discharged into the lower Liffey Estuary. This will safeguard the environment of Dublin Bay, and ensure that the plant operates in compliance with the Urban Wastewater Treatment Directive standards.

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.

There are four key elements to the upgrade project:

  • Provision of additional secondary treatment capacity with nutrient reduction (400,000 population equivalent) due for completion in the second half of 2021;
  • 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;
  • Provision of a new phosphorous recovery facility; and
  • Expansion of the plant’s sludge treatment facilities.

Irish Water is working to provide infrastructure to achieve compliance with the Urban Wastewater Treatment Directive for a population equivalent of 2.1 in the second half of 2023. When all the proposed works are complete in 2025, the Ringsend Wastewater Treatment Plant will be able to treat wastewater for up to 2.4 million population equivalent while meeting the required standards.

Irish Water continues to work at this time with our Local Authority partners, contractors and others to safeguard the health and well-being of both staff and the public and to ensure the continuity of critical drinking water and wastewater services.