Successful HDD for Cork Harbour

Irish Water has completed the installation of two pipes using horizontal directional drilling (HDD) at the Cork Lower Harbour Main Drainage Project.

In partnership with Cork County Council, Irish Water is working to end the practice of discharging raw sewerage directly into Cork Lower Harbour with its drainage project.

Last week, Irish Water completed the sewer pipe installation in the second and final drilled bore that extended more than 1 km under the Lee Estuary between Cobh and Monkstown.

Irish Water said this landmark engineering feat includes two of the longest HDD’s ever carried out in Ireland.

Cork Lower Harbour Main Drainage Project Manager Déaglán Healy said the team is delighted to have successfully and safely completed the drill and installation works for the contract.

“We’d like to thank [the local community] for working with our contractor for the works, O’Connor Utilities, who have worked tirelessly, in partnership with Long O’Donnell, Nicholas O’Dwyer and our own Irish Water project team, to ensure the safe completion of these works while minimising the impact on the local community as much as possible,” said Mr Healy.

The successful installation completes the works under the estuary and creates the vital connection between Cobh and Monkstown.

The new connection will allow the raw sewage from Cobh to be transferred for treatment, following completion of Cobh Town Networks’ contracts in 2021.

For more information visit the Irish Water website.

If you have news you would like featured in Trenchless International contact Head of Production Chloe Jenkins at

The above article was originally published in Trenchless International, the official publication of the ISTT. For further information visit  

Privacy Preferences
When you visit our website, it may store information through your browser from specific services, usually in form of cookies. Here you can change your privacy preferences. Please note that blocking some types of cookies may impact your experience on our website and the services we offer.