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.

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