Texas Special District Local Laws Code - SDLL § 7803.108. Construction Contracts: Payment

(a) A construction contract may be paid for in partial payments as the work progresses, based on estimates approved by the district's engineer.

(b) The payments may not exceed 90 percent of the amount due at the time of the payments as shown by the approved estimates, except that the final approved estimate, including all prior retainage, must be paid in full. (Acts 62nd Leg., R.S., Ch. 135, Sec. 15 (part).)