Guernsey Harbour's work boat, which has been in service for 30 years, is being retired.
The Sarnia has been looking after the harbour and buoys at sea since the late 1980s.
A new, specially designed boat is being made by a Southampton company.
Crews are expected to have more useable space and a safer working environment.
The new vessel will help harbour workers with towing other boats, moving equipment, repairing, beacon and buoy maintenance and diving activities.