Where a highway maintainable at the public expense consists of or comprises a made-up carriageway, the highway authority liable to maintain it may construct and maintain works in that carriageway—
along any length of the highway, for separating a part of the carriageway which is to be used by traffic moving in one direction from a part of the carriageway which is to be used (whether at all times or at particular times only) by traffic moving in the other direction;
at crossroads or other junctions, for regulating the movement of traffic.
The powers conferred by subsection (1) above include power, in relation to any such works as are referred to in that subsection—
to light them,
to pave, grass or otherwise cover them or any part of them,
to erect pillars, walls, rails or fences on, around or across them or any part of them, and
to plant on them trees, shrubs and other vegetation either for ornament or in the interests of safety.
A highway authority may alter or remove any works constructed by them under this section.
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