Notions like "public" and "interested public" are used to identify the citizens who are directly affected by the project and not vested with administrative responsibilities, but taking part in the process of decision-making and implementation.
Public is one or several physical or legal entities, excluding persons or organisations formally responsible for taking decisions about a certain issue like:
One can make a separation between the "public" and the "interested public". The term "interested public" has a restricted character in the sense that it is public that is, assumably, organised and well informed and only related to a certain project or issue. The term "public" may be associated with all people usually not very well informed and only indirectly involved in decision making.