Texas Local Government Code - LOC GOV'T § 375.071. Quorum

(a) One-half of the serving directors constitutes a quorum, and a concurrence of a majority of a quorum of directors is required for any official action of the district.

(b) If at least two-thirds of the directors execute a written consent at any time, a majority of a quorum at a board meeting may authorize the levy of assessments, the levy of taxes, the imposition of impact fees, or the issuance of bonds.A director may execute a written consent outside of a board meeting.