No inland port authority shall be required to pay any taxes or any assessments whatsoever to the State of Nebraska or to any political subdivision of the state, except for assessments under the Nebraska Workers' Compensation Act and any combined tax due or payments in lieu of contributions as required under the Employment Security Law. The bonds of every inland port authority and the income therefrom shall, at all times, be exempt from any taxes and any assessments, except for inheritance and gift taxes and taxes on transfers.