After the board adopts plans for construction of a plant and improvements to accomplish the purposes of the district and after an election is held to authorize the issuance of construction bonds and the levy of a tax to pay for the bonds, the board shall hold a public hearing to determine whether the taxes to pay the construction bonds and maintenance, operation, and administrative costs of the district shall be levied, assessed, and collected on:

1. (1) the ad valorem basis;
2. (2) the basis of assessment of specific benefits;
3. (3) the basis of assessment of benefits on an equal sum per acre; or
4. (4) the ad valorem basis for part of the total tax or defined area or property and on the benefit basis for the other part of the tax or defined area or property.

Acts 1971, 62nd Leg., p. 349, ch. 58, Sec. 1, eff. Aug. 30, 1971.