The cost of a street improvement shall be paid by assessment of a special or local tax on the abutting lots and parcels of land in the manner provided by law, the urban county government paying for the improvements of intersections with other streets; but mere repairs, not amounting to a reconstruction or resurfacing, shall be paid for by the urban county government out of its general fund. If any improvement is made on the ten-year or other annual payment plan, the urban county government will, upon completion and acceptance of the work, issue bonds for such part of the cost thereof as may not be paid in cash and for the payment of which agreements are signed as provided by law, and will apply the proceeds of such bonds, when sold, or deliver them to the contractor as provided by statute in payment of such work. Such bonds will be exempt from taxation by the urban county government.