noun
harbor duties; port dues
A tax or fee levied on vessels using a port; a technical term in maritime and customs contexts.
船舶が入港する際には、港湾税を支払う必要がある。
When a vessel enters the port, it is necessary to pay harbor duties.
入港料 is a more general term for port entry fees, whereas 港湾税 specifically refers to a tax or duty.
Compound of 港湾 (port, harbor) and 税 (tax, duty).