The largest engineering project of its type ever undertaken in this country will start shortly in Cork's lower harbour.
The final phase of the €144m Cork Lower Harbour Main Drainage project is to get underway in Cobh and residents have been warned that because of its scale they will face disruption.
The main drainage project is designed to treat the equivalent of 40,000 wheeliebins of raw sewerage which are currently discharged into the harbour every day.
The project has been underway since 2015 and since then the Shanbally Wastewater Treatment Plant has been commissioned and is treating sewerage from Ringaskiddy, Crosshaven, Carrigaline, Passage West and Monkstown. It is treating the equivalent of 30,000 wheelie bins of raw sewerage every day.
Work is now getting underway on transferring raw sewerage from the Cobh side of the harbour to the Shanbally treatment plant.
Déaglán Healy, the project manager, said this will entail digging up a number of Cobh streets to lay pipes and create pumping stations.
However, the largest part of the project will be the creation of an underwater pipeline, which will run from a new pumping station at Verlome Dockyard across the channel to The Glen, Monkstown.
Mr Healy said:
This will be a very big exercise. We will be bringing in a 400 tonne drilling rig from the UK for this. It's the only one of its type in the UK and this is the biggest engineering operation of its type ever to be done in this country.
The rig will drill into the sub water rock, which will be up to 150 feet below water level, and it will span the 1km wide channel.
Mr Healy said the Cobh element of the overall project was costing approximately €60m.
The drilling rig will arrive in the town in the next couple of weeks and drilling will start as soon as it is in situ. It is expected to be completed by next February or March.
Meanwhile, a lot of work will be undertaken in the next few months on laying new sewerage pipelines in Cobh itself.
Mr Healy said this work will start next month and will go on throughout the winter.
The road at East Beach will be closed for eight weeks and the road at Summer Point, near Verlome Dockyard, will close for five weeks to facilitate this work.
Similar road closures are planned for Harbour View, Harbour Row and Connolly Street in 2020.
Pipelaying work will not take place during the summer season as Mr Healy said Irish water took onboard submissions from the local chamber of commerce and tourist interests that if it did it could significantly damage the town's tourism, especially in relation to visiting cruise liners.
However, Irish Water contractors will continue to work on creating new pumping stations in the town as these will be screened off.
"We appreciate people's cooperation with the project as we are going to be disrupting and delaying them. We would ask people to start off on their journeys earlier than normal because of the delays which will occur," Mr Healy said.
He said he would encourage Cobh residents and businesses to contact the project team and register for regular project updates at firstname.lastname@example.org.
It is hoped to have the Cobh pipelines and the underwater connection will be commissioned in late 2021.
When this is one it will make the completion of the whole project which will result in the connection of 20,000 homes and businesses to the treatment plant.