(a) An authority confirmed before July 1, 1985, may, in the authority:
(1) construct or maintain a highway, local or arterial street, thoroughfare, or other road, including a bridge or grade separation; and
(2) install or operate traffic control improvements, including signals.
(b) An authority confirmed before 1985 may, in the authority:
(1) construct or maintain a sidewalk, hiking trail, or biking trail;
(2) install or maintain streetlights; and
(3) in performing an activity under Subdivision (1) or (2), make drainage improvements and take drainage-related measures as reasonable and necessary for the effective use of the transportation facility being constructed or maintained.

(c) An authority may perform an activity authorized by this section through an agreement with another governmental entity, including an agreement under Chapter 791, Government Code, with a state agency listed under § 771.002, Government Code.
(d) An authority may not perform an activity authorized by this section in a municipality without:
(1) the consent of the governing body of the municipality; or
(2) a contract with the municipality specifying the actions that the authority may undertake.
(e) Subsection (a) does not apply to the performance of an action undertaken by the authority under § 451.056(a)(1) or 451.058.
(f) This section does not apply to an authority created before 1980 in which the principal municipality has a population of less than 1.9 million.