A professional who commands vessel equipped with machinery for excavating under water to facilitate building structures in harbors, estuaries, straits, sounds, rivers, lakes, bays, and oceans. Responsibilities include:

• Sets course of vessel, using navigational aids, such as charts, area plotting sheets, compass, and sextant, and orders worker at helm to steer ship toward excavation site.
• Determines geographical position of ship, using loran or azimuths of celestial bodies.
• Directs crew engaged in operating deck winches and lowering dredging equipment.
• Supervises crew engaged in dredging operations.
• Verifies depth of excavations to ensure that excavations are made according to requirements.
• Maintains ship's log.
• Must be licensed by U.S.
• Coast Guard for steam, motor, or sail ship according to waters navigated and tonnage of ship.