43 Tex. Admin. Code § 28.20
In accordance with Transportation Code, Chapter 623, Subchapter K, the department may authorize the Brownsville Navigation District of Cameron County, Texas (Port of Brownsville) to issue permits for the movement of oversize or overweight vehicles carrying cargo on State Highway 48/State Highway 4 between the Gateway International Bridge and any location along that highway within the Port of Brownsville, or on U.S. Highway 77/U.S. Highway 83 and State Highway 48/State Highway 4 between the Veterans International Bridge at Los Tomates and any location along that highway within the Port of Brownsville or from the Free Trade International Bridge to the entrance of the Port of Brownsville using Farm-to-Market Road 509, United States Highways 77 and 83, Farm-to-Market Road 511, State Highway 550, and East Loop (State Highway 32). This subchapter sets forth the requirements and procedures applicable to the issuance of permits by the Port of Brownsville for the movement of oversize and overweight vehicles.
43 Tex. Admin. Code § 28.20