Haw. Rev. Stat. § 39A-356: Exemption from taxation of department property.

All revenues derived by the department from any project or under the project agreement pertaining thereto shall be exempt from all state and county taxation. Any right, title, and interest of the department in any project shall also be exempt from all state and county taxation.

Except as otherwise provided by law, the interest of the project party or user of the project under the project agreement or related agreement shall not be exempt from taxation to a greater extent than it would be if the costs of the project were directly financed by the project party or other user.