The Department of Infrastructure says the footbridge across Peel harbour will be out of action for four weeks in September.
The Fenella bridge linking East and West Quays needs planned maintenance work to overhaul hydraulic systems, and will also be repainted.
Work is due to get underway on Monday, September 8.
The flap gate will be unaffected by the work, and the DOI says vessels will still be able to enter and leave the inner harbour.
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