(a) The proceeds of county bonds may be paid out only by the county treasurer on warrants:
(1) drawn on the available road fund;
(2) issued by the county clerk;
(3) countersigned by the county judge; and
(4) on certified accounts approved by the commissioners court.
(b) The proceeds of bonds issued on the faith and credit of a commissioners or justice precinct or a road district may be paid out only by the county treasurer on warrants:
(1) drawn on the available road fund of the applicable political subdivision;
(2) issued by the county clerk;
(3) countersigned by the county judge; and
(4) approved by the commissioners court.