(1) A person commits an offence who impedes the free flow of water in, or dam or fills up or otherwise obstruct—
(a) any ditch or drain adjoining any road;
(b) any ditch, drain or watercourse from any road which shall be connected with any ditch, drain or watercourse being in or upon any land;
(c) any ditch, drain, or watercourse on any land into or through which the water of any ditch, drain, or watercourse in the last preceding subsection mentioned shall flow; or
(d) any ditch, drain or watercourse under any road.
(2) It is lawful for the Authority to do all things necessary for effectually removing every such obstruction at the cost of the person so offending.