The board of flood irrigation of any flood irrigation project shall have the right upon the payment of all the bonded debt of the flood irrigation project, by resolution, to transfer any and all funds then remaining in the sinking fund of the project to the maintenance fund of the project for use in maintenance, repair and care, and for payment of outstanding and unpaid warrants issued for maintenance of the project. The county treasurer as custodian of the funds of any flood irrigation project, of any county in this state, shall upon receipt of a certified copy of a resolution of any board of flood irrigation, showing that all bonded debt of a flood irrigation project has been fully paid, transfer any and all funds then remaining in the sinking fund of the project to the maintenance fund of the project.