Tex. Util. Code § 121.155
A gas utility the rates of which have been reduced by a municipality may appeal the municipal order, decision, regulation, or ordinance to the railroad commission. The appeal is initiated by filing with the railroad commission in the manner and on the conditions that the railroad commission may direct a petition for review and a bond. The appeal is de novo. The railroad commission shall set a hearing and may make any order or decision in relation to the matter appealed that the commission considers just and reasonable. To change a rate, rental, or charge, a gas utility that is a local distributing company or concern and the rates of which have been established by a municipality must submit an application to the municipality in which the utility is located. The municipality shall make a determination on an application not later than the 60th day after the date the application is filed. If the municipality rejects the application or fails or refuses to act on the application on or before the deadline prescribed by this section, the gas utility may appeal to the railroad commission as provided by this section. The railroad commission shall make a determination on the appeal not later than the 60th day after the date the appeal is filed unless the gas utility agrees in writing to a longer period. The rates established by the municipality remain in effect until changed by the railroad commission.
Tex. Util. Code § 121.155