Past: The graffiti was put in by individuals, there is no regulation or sponsorship. When the mill was abandoned, it was a canvas for whoever came upon it. Those who marked the walls with graffiti signified that the space was theirs. The graffiti marks an important part of the mill and surrounding district’s history; the area was not always desirable or in favorable use.
Present: This sign is public, I would guess put in by a state sponsored agency. The area is currently highly desirable and in acceptable public use. People are encouraged to live, tour, and exercise in the area. It is also a highly sought out location for portraits for school or events. This is distinctly different from the Past photo, where although the area was still in public use, it was not in acceptable or desirable public use.
Future: This sign in private, indicating area intended only for certain people. The area around the mill is now high end housing, which is mixed into publicly used space. It could be a space for more retail development which then could lead to more signs like this, indicating that public use is restricted and monitored.