(a) The bridge or bridges shall be paid for by special tax, not to exceed, in any year, twenty cents (20¢) on the one hundred dollars' ($100) worth of property, to be levied by the county legislative body annually on all taxable property of the county, until the bridge or bridges are paid for, or until the interest-bearing warrants or bonds provided for in this part are redeemed.
(b) Nothing in this part shall prevent the county legislative body from paying for the bridge or bridges or redeeming any or all of the warrants or bonds, out of any moneys or funds in the county treasury not otherwise appropriated.