(a) A county may impose ad valorem taxes as provided by Section 1-a, Article VIII, Texas Constitution, for the construction and maintenance of farm-to-market and lateral roads or for flood control, not to exceed the maximum tax rate established by that section, only if the taxes are approved at an election held under this section.
(b) The commissioners court of the county may order an election under this section on its own motion. The court shall order an election under this section if it receives a petition requesting the election signed by a number of registered voters of the county equal to at least 10 percent of the number of voters who voted in the most recent general election in the county. The court may adopt the order only at a regular session of the court. The order must specify the maximum rate of the tax to be voted on.

(c) The proposition submitted to the voters at the election may provide that the tax may be used for the construction and maintenance of farm-to-market and lateral roads, for flood control purposes, or for both, as determined by the commissioners court. At an election to adopt a tax for only one of those purposes, the ballot shall be printed to permit voting for or against the proposition: “Adopting a tax not exceeding ___ cents on each $100 valuation,” specifying the purpose of the tax to be voted on. At an election to adopt a tax for each of those purposes, the ballot shall be printed to permit voting for or against the proposition: “Adopting a farm-to-market and lateral roads tax not exceeding ___ cents and a flood control tax not exceeding ___ cents on each $100 valuation.”
(d) In addition to the notice of the election required by Section 4.003, Election Code, the county judge shall post a copy of the election order at a public place in each county election precinct not later than the 14th day before the date of the election.
(e) If a majority of the votes received in the election favor adoption of the tax, the commissioners court shall impose the tax each year in the same manner as other county ad valorem taxes.
(f) The commissioners court may call a subsequent election to change the maximum rate of a farm-to-market and lateral road tax or flood control tax previously adopted by the county in the manner provided by this section for an election to adopt a tax.
(g) The commissioners court of a county that adopts a tax as provided by this section may issue negotiable county bonds or county time warrants for the construction or improvement of farm-to-market and lateral roads or the construction of permanent improvements for flood control purposes if the bonds or warrants are authorized by a majority of the votes received in an election ordered by the commissioners court. The commissioners court shall submit each proposition separately at the election. The commissioners court shall issue the bonds or warrants and impose the taxes for those bonds or warrants as provided by Subtitles A and C, Title 9, Government Code.