Taoiseach Micheál Martin has opened the final piece of infrastructure for the Cork Lower Harbour Main Drainage Scheme, a €144 million investment by Irish Water which paves the way for a significant improvement in water quality in the harbour.

Mr Martin opened a pumping station at Cork Dockyard which will transfer raw sewage from the town of Cobh to Shanbally on the other side of the harbour, via an under-estuary crossing.

Up to now, raw sewage from Cobh was pumped directly into Cork Harbour through 19 outflow pipes.

However, the opening of the pumping station means 20,000 homes and businesses in Cobh and other harbour towns, such as Ringaskiddy, Crosshaven, Carrigaline, Passage West and Monkstown, have all be connected to the scheme.

Taoiseach Micheál Martin and Eamon Gallen of Irish Water

At the opening of the Cork Dockyard pumping station earlier today, Micheál Martin said the improvement in water quality in Cork Harbour would provide new opportunities for sustainable social and economic development.

"We have already seen the benefits that this project has brought to Ringaskiddy, Shanbally, Crosshaven, Carrigaline, Passage West and Monkstown," Mr Martin said.

"This final stage will add to that improvement, providing further capacity for growth and enhancing the wonderful amenity that is Cork Harbour, the second largest natural harbour in the world."

It has taken two years to expand the sewer network in Cobh. Seven kilometres of new sewer pipes were laid in Cobh, and five new pumping stations were built there. Waste from Cobh is pumped to the treatment plant at Shanbally through a newly-constructed estuary crossing, 60 metres below the harbour.

Prior to this, raw sewage from Cobh and surrounding areas was pumped directly into Cork Harbour, via 19 outflow pipes.

This practice was in breach of national and European legislation. Ireland is currently in contravention of the European Union Urban Wastewater Treatment Directive.

The Cobh networks contract is the final part of the Cork Lower Harbour Main Drainage Scheme

The provision of secondary wastewater treatment into the harbour is a requirement of European and National legislation.

The Cobh networks contract is the final part of the Cork Lower Harbour Main Drainage Scheme. This expanded network collects the raw sewage from the town of Cobh that, until now, discharged untreated directly to the harbour.

The raw sewage is pumped to the Cork Dockyard pumping station and then transferred for treatment to Shanbally Wastewater Treatment Plant via the Lee Estuary Crossing, linking Cobh to Monkstown, before its safe discharge to sea.

This last step in the Cork Lower Harbour main drainage project means that all wastewater from the area is now being treated, in compliance with the Urban Waste Water Treatment Directive.

The areas covered by the scheme include:

* Ringaskiddy-Crosshaven-Carrigaline

* Ringaskiddy village

* Passage West-Monkstown

* Cobh town

Mayor of Cork County Council, Cllr Gillian Coughlan said: "The ending of raw sewage discharges from Cobh town will make a huge difference to the town and surrounding area, by providing opportunities for sustainable development around Cork Lower Harbour and increasing the potential for tourism and recreational activities in the area."

Eamon Gallen, Irish Water's General Manager, said: "Today is a hugely significant milestone in Irish water's work to eliminate raw sewage discharges in Ireland.

"The completion of this work brings to 17 the number of towns and villages across the country where Irish Water has built new wastewater infrastructure since 2014.

"Well over half of the raw sewage entering waterways in Ireland has now been eliminated and we are on track to fully remove the majority of raw sewage discharges in Ireland by 2025.

"This represents an overall investment of €650 million towards improving water quality in our rivers, lakes and seas, ensuring compliance with Irish and European legislation to the benefit of our local communities, our environment and our economy."