Tex. Water Code § 51.454

If a district issues its original bonds under Section 51.450(b)(2) of this code and later desires to issue bonds payable in whole or in part from taxes or to levy a tax for maintenance purposes, the district shall hold a hearing to exclude land, and at the time provided by law, shall hold another hearing to adopt a plan of taxation. These hearings shall be held before an election is called to approve the issuance of tax-supported bonds or the levy of a maintenance tax.