I see you mention a pier ... one thing we encountered was with an area with open water - not barriered off, in the general course of events so you might think, 'well, we don't need to worry about it'. However, if YOU are inviting people to that area .. it becomes your problem. You might need to think about how you stop people (& children) falling into the water ... without actually preventing those people who have a right to access the edge of the pier (fishermen / boaters etc) from being able to do so.