The board of directors shall adopt a resolution setting forth in general terms the amount of money proposed to be raised by the levy and the project or portion thereof which is to be financed by the proposed levy. The proposed amount may be the total estimated amount payable under any contract awarded for improvement, or for any portion thereof, or for any excess of cost over the amount of any past levies already made for that purpose. There shall first be deducted from the amount of the levy any amount to be contributed thereto by the State and the balance of the levy shall be distributed among the several counties composing the district in the proportions set forth in the report of the board of directors.