The provisions of this Part of this Act have effect for the purpose of empowering or requiring highway authorities and other persons to improve highways.
Without prejudice to the powers of improvement specifically conferred on highway authorities by the following provisions of this Part of this Act, any such authority may, subject to subsection (3) below, carry out, in relation to a highway maintainable at the public expense by them, any work (including the provision of equipment) for the improvement of the highway.
Notwithstanding subsection (2) above, but without prejudice to any enactment not contained in this Part of this Act, work of any of the following descriptions shall be carried out only under the powers specifically conferred by the following provisions of this Part of this Act, and not under this section—
A highway authority may alter or remove any works executed by them under this section.
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