30 Tex. Admin. Code § 293.150
A district may request a variance to § 293.142(a) and (c) of this title (relating to Application Requirements for Imposition of Standby Fees To Be Used To Supplement the Debt Service Account) and §293.143(b), (c), and (d) of this title (relating to Application Requirements for Standby Fees To Be Used To Supplement the Operation and Maintenance Fund) if it does not meet the guidelines contained in § 293.142(a) of this title or § 293.143(b) of this title; a majority of a district's board of directors finds by resolution that the district would be justified in requesting a variance; the fee was in place on August 28, 1989, and had been previously approved by the commission; and the elimination of the fee would cause a significant increase in the taxes or rates currently being assessed by the district. The district will be responsible for providing sufficient documentation to justify any request for a variance. The commission will only grant variances in exceptional cases and may deny any request for a variance.
30 Tex. Admin. Code § 293.150