.Whoever wilfully obstructs any person in doing any of the acts authorised by section 4 or section 8, or wilfully fills up, destroys, damages or displaces any trench or mark made under section 4, shall, on conviction before a Magistrate, be liable to imprisonment for any term not exceeding one month, or to fine not exceeding [five hundred rupees] [Substituted by Act 68 of 1984, Section 26, for " fifty rupees " (w.e.f. 24.9.1984).], or to both.