(1) In all the viaduct improvement districts described in § 14-321-101, limitations on bonds that may be issued by a district shall not apply to interest on any bonds or borrowed money.
(2) If bonds are issued before the construction work is completed, limitations on the issuance of bonds to a part of the total cost of construction shall apply to the estimated total cost of construction as estimated by the engineer for the district and approved by the commissioners at the time the bonds are issued. Bonds may be issued from time to time on revisions of the estimates.