Catseyes being installed on the New Castletown Road will mean a series of daytime road closures from next week.
The DOI says work will start on Tuesday, May 6 on the stretch between Glashen Hill roundabout and Orrisdale Road.
That section will shut at 9.30am until 3.30pm.
The department says it hopes to finish the entire road by Friday 16 May.
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