(a) The following highways are designated as the Texas portion of the national Purple Heart Trail:
(1) the part of Interstate Highway 35 located in Texas;
(2) the part of Interstate Highway 40 located in Texas;
(3) the part of Interstate Highway 37 from Interstate Highway 35 to U.S. Highway 77;
(4) the part of U.S. Highway 77 from Interstate Highway 37 to State Highway 100;
(5) State Highway 100;
(6) Park Road 100;
(7) the part of U.S. Highway 83 Business in Hidalgo and Cameron Counties; and
(8) State Highway 195.
(b) The department shall design and construct markers indicating the highway number, the designation as the Purple Heart Trail, and any other appropriate information.
(c) The department shall erect a marker at locations along the trail that the department determines are appropriate.
(d) Notwithstanding Subsections (b) and (c), the department is required to design, construct, and erect the markers only to the extent that money is available for this purpose from donations received from local Purple Heart organizations.
(e) Money received under Subsection (d) shall be deposited to the credit of the state highway fund for dedication under this section.
(f) The designation under Subsection (a)(8) is in addition to any other designation.