Unexpected ground conditions have "impacted the delivery programme"
Uisce Éireann is extending the road closure on the R405 Hazelhatch Road until Friday 15 January 2027.
It says unexpected ground conditions have "impacted the delivery programme".
UÉ says the extension is required to facilitate the completion of essential water, stormwater and telecommunications infrastructure currently being delivered along Hazelhatch Road.
The project involves the replacement of "ageing water infrastructure", together with the installation of a new surface water pipeline and telecommunications ducting on behalf of South Dublin County Council.
It says that delivering these three utilities through a single co-ordinated programme is a "more efficient and less disruptive" approach than completing the works separately.
To date, 1,500 metres of water main has been replaced, 1,250 metres of surface water pipeline has been installed, and 950 metres has been completed on the telecommunications ducting.
The new infrastructure will also support future development in Newcastle and Celbridge, including approximately 3,500 new homes across three sites.

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