Haw. Rev. Stat. § 47-13
All bonds heretofore or hereafter issued under the authority of this chapter and the income therefrom shall be exempt from any and all taxation by the State or any county or other political subdivision thereof, except inheritance, transfer, and estate taxes.
The interest and principal payments of bonds issued under this chapter shall be a first charge on the general fund of the county issuing same, and sufficient revenues shall be raised or provided from time to time by the county for the purpose of that payment. The governing body of any county issuing bonds under this chapter shall appropriate out of the general fund of the county all amounts necessary for the payment of the principal of and interest on the bonds as and when the same become due, and the appropriation shall be a paramount appropriation upon the general fund of the county issuing same.
HRS § 47-13