A. The board of directors of a sanitary district shall sell bonds issued pursuant to section 48-2021, subsections A, B, C and D at not less than par value at public sale or if the district has a population of more than two thousand persons and has been in existence for ten or more years at public or private sale, and the proceeds shall be placed in the county treasury to the credit of the district. All premiums and accrued interest received shall be paid into the bond fund of the district to be used for payment of principal of and interest on the bonds, and the remainder of the proceeds shall be paid into the construction fund of the district. The county treasurer shall keep an accurate record of all monies of the district paid to him.

B. The construction fund shall be used exclusively for the purposes mentioned in the resolution calling the bond election. Payments from the construction fund shall be made upon claims allowed by the board of directors of the district, prepared, presented and audited in the same manner as claims upon county funds.