The Department of Infrastructure says it'll increase charges for berthed boats by more than 19 per cent this year.
When Tynwald sits on Tuesday, members will be asked to increase harbour dues under new regulations.
The DOI says some pleasure craft are being berthed against harbour walls and abandoned, and ageing port infrastructure is in urgent need of investment.
As a result, it says it'll put those harbour dues up by 19.26 per cent, with further increases planned in the next three years.
Should cohabiting couples get married tax breaks?
Repairs on Peel Power Station to get underway
Manx Care doctor survey to be discussed by Tynwald
Weather warning for snow tonight
MHK queries safety at primary school in Ballabeg
Gales put two ferry sailings at risk tonight
Should the Island throw a birthday party for Barry Gibb?
Warning issued over icy roads