(a) If a district levies taxes on the benefit basis, the commissioners court of each county in which any portion of that district is located shall levy and have assessed and collected taxes on all taxable property inside the district, based on the net benefits which the commissioners of appraisement find will accrue to each piece of property from the improvements described in the engineer’s report or other authorized improvements.
(b) The taxes shall be sufficient to pay the interest on the bonds, as it is due, and to raise an amount to create a sinking fund sufficient to discharge and redeem the bonds at maturity.

(c) The levy for each year throughout the life of the bond issue may be made at the time the bonds are issued and shall be the rate of levy for each year until it is modified.