Tex. Water Code § 36.016

(a) If the commission certifies a petition to create a district under Section 36.015, the commission shall appoint the temporary directors named in the petition. If the commission dissolves a district's board under Section 36.303, it shall appoint five temporary directors.

(b) If the commission creates a district under Section 36.0151, the county commissioners court or courts of the county or counties that contain the area of the district shall, within 90 days after receiving notification by the commission under Section 36.0151(b), appoint five temporary directors, or more if the district contains the territory of more than five counties, for the district's board using the method provided by Section 36.0161. A county commissioners court shall not make any appointments after the expiration of the 90-day period. If fewer than five temporary directors have been appointed at the expiration of the period, the commission shall appoint additional directors so that the board has at least five members.

(c) Temporary directors appointed under this section shall serve until the initial directors are elected and have qualified for office or until the voters fail to approve the creation of the district.

(d) If an appointee of the commission or of a county commissioners court fails to qualify or if a vacancy occurs in the office of temporary director, the commission or the county commissioners court, as appropriate, shall appoint an individual to fill the vacancy.

(e) As soon as all temporary directors have qualified, the directors shall meet, take the oath of office, and elect a chairman and vice chairman from among their membership. The chairman shall preside at all meetings of the board and, in the chairman's absence, the vice chairman shall preside.