The move is expected to be met with opposition.
The OPW has taken to social media to announce that essential contractors and suppliers will access Castletown estate daily via Lime Avenue.
The video said Lime Avenue is not suitable for high volumes of traffic, but it is currently the "only route available to the OPW".
Starting on Monday, four to five essential service vehicles will access the site daily.
The video said the vehicles will be escorted by a speed limited buggy going no more than 10kms once access through the gate is established.
The move is expected to be met with opposition.

Tallaght Hospital Set To Withdraw Post-Mortem Cover Services From Naas Hospital In 2027
Kfm Obituary Notices
Kildare Motorist Caught Speeding Was In Rush To Buy Pizza Before Takeaway Closed
Over 19,000 Kildare Students To Take Part In Maths Week Ireland 2026
New Funding Announced For Youth Services And Counselling In Kildare On World Mental Health Day