Tex. Water Code § 16.231

Insofar as possible, improvements necessary to reclaim overflowed land, swampland, and other land in this state that is not suitable for use because of temporary or permanent excessive accumulation of water on or contiguous to the land for agricultural or other use shall be designed with primary consideration to the topographic and hydrographic conditions and in such a manner that each division of a project shall be a complete, united project forming a coordinate part of an ultimately finished series of projects so constituted that the successful operation of each united project shall coordinate with the successful operation of other projects within the same hydraulic influence.