(a) The circuit court, in determining the question of whether the cost of the improvement exceeds the benefits, shall be required to take into consideration only the amount that the district will be required to pay for the cost of the improvement. It shall credit against the total cost of the bridge and approaches thereto any and all grants or allocations of money made by the federal government through the Federal Highway Administration, grants of state aid made by the State Highway Commission, state aid made by the state or highway commission of any adjoining state, aid and grants from any county, city, or town of this state or adjoining state, and the annual amounts to be received by the district from tolls collected as provided in this chapter, and other financial assistance the district may receive from any other sources whatsoever.
(b) The interest to accrue on account of the issuance of bonds by the district shall not be construed as a part of the cost of construction.