Texas Natural Resources Code - NAT RES § 61.014. Denial of Access by Posting

(a) As used in this section, “public beach” means the area extending from the line of mean low tide of the Gulf of Mexico to the line of vegetation bordering on the Gulf of Mexico, or to a line 200 feet inland from the line of mean low tide, whichever is nearer the line of mean low tide, if the public has acquired a right of use or easement to or over the area by prescription, dedication, or has retained a right by virtue of continuous right in the public.

(b) No person may display or cause to be displayed on or adjacent to any public beach any sign, marker, or warning, or make or cause to be made any written or oral communication which states that the public beach is private property or represent in any other manner that the public does not have the right of access to the public beach as guaranteed by this subchapter.