A highway authority may construct road humps in a highway maintainable at the public expense for which they are the highway authority if—
the highway is subject to a statutory speed limit for motor vehicles of 30 miles per hour or less; or
(whether or not the highway is subject to such a limit)the road humps are specially authorised by the Secretary of State, or
(whether or not the highway is subject to such a limit) the road humps fall within section 90CA below.
and may remove any road humps so constructed by them.
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