The Cork Dockyard Pumping Station outside Cobh transfers sewage from Cobh for treatment before the water is pumped into the harbour.
Irish Water say the project which began in 2014 will protect the environment and improve water quality.
Speaking to RedFM News, Déaglán Healy from Irish Water outlines what they have achieved in the past seven years:
"When we started, the equivalent of 40,000 wheelie bins of raw sewage was discharging into Cork Harbour every day. We built a state of the art wastewater treatment plant in Shanbally and connected existing networks in Crosshaven and Carrigaline to the plant, so that half of this sewage was treated by 2017. We expanded the sewer network to connect the towns of Ringaskiddy, Shanbally, Passage West and Monkstown, by early 2019."
