30 Tex. Admin. Code § 298.290
The adopted environmental flow standards or environmental flow set-asides for the Sabine and Neches Rivers, their associated tributaries, and Sabine Lake Bay may be revised by the commission through the rulemaking process. The Sabine and Neches basin and bay area stakeholder committee shall submit their review of the adopted environmental flow standards by September 1, 2013, and every five years thereafter. If the stakeholder committee recommends revisions to the adopted environmental flow standards, or, if the commission determines that revisions to the adopted environmental flow standards are appropriate at the time of the periodic review, the rulemaking process shall be undertaken in conjunction with the periodic review. Any final revised rules arising from a rulemaking undertaken in conjunction with any such periodic review shall be effective within one year after the deadline for the review of the adopted environmental flow standards. The rulemaking process shall include participation by a balanced representation of stakeholders having interests in the Sabine and Neches Rivers, their associated tributaries, and Sabine Lake Bay.
30 Tex. Admin. Code § 298.290