(a) The department shall repair and replace each marker required by this subchapter and maintain the grounds for the marker.
(b) The department shall accept a grant or donation made to assist in financing the construction and maintenance of a marker.
(c) The department may not design, construct, or erect a marker under this subchapter unless a grant or donation of funds is made to the department to cover the cost of the design, construction, and erection of the marker.
(d) Money received under Subsection (b) shall be deposited to the credit of the state highway fund.