Texas Water Code - WATER § 11.044. Roads and Highways

(a) An appropriator has the right to construct ditches, canals, or pipelines along or across all roads and highways necessary for the construction of waterworks.  Bridges, culverts, or siphons shall be constructed at all road and highway crossings as necessary to prevent any impairment of the uses of the road or highway.  Approval of the construction plans and specifications shall be obtained from the owner of the road or highway prior to the installation of conveyance facilities.

(b) If any public road, highway, or public bridge is located on the ground necessary for a damsite, reservoir, or lake, the commissioners court shall change the road and remove the bridge so that it does not interfere with the construction of the proposed dam, reservoir, or lake.  The party desiring to construct the dam, reservoir, or lake shall pay the expense of moving the bridge or roadway.