9. A person who, without lawful authority—
(a)intentionally or recklessly obstructs any person acting under the authority of the Commissioners in setting out the lines of the authorised works; or
(b)interferes with, moves or removes any pole, stake, station point or bench mark established for the purpose of such setting out,
shall be guilty of an offence and liable on summary conviction to a fine not exceeding level 4 on the standard scale.