Any person who, without lawful authority, places any structure or object so as to obstruct the free passage over any part of the waterside to which the public have access shall be guilty of an offence and liable on summary conviction to a fine not exceeding level 3 on the standard scale and in addition, in the case of a continuing offence, a daily fine not exceeding one-tenth of that level.

Nothing in subsection (1) above shall apply to anything done on any land by or with the consent of the occupier of the land.