The board of county commissioners of any county in which any flood irrigation project is proposed to be located and constructed shall issue bonds upon the written request of the board of flood irrigation. Such bonds shall be known as flood irrigation bonds and shall be in such sums as may be necessary for the purpose of defraying the expenses incurred or to be incurred in obtaining the right of way or in locating or constructing any such project. The word “expenses” as used in this section shall be construed to cover every item of cost of said project from its inception to its completion as provided by this chapter. Such bonds shall be paid out of the revenues to be derived from taxes levied or to be levied and collected from that portion of the county found by the board of flood irrigation to be benefited by the project.