Sam, the owner of a private Arizona security firm, stopped the truck and put the gear in park.

"We're on the Roosevelt Easement right now," he says bluntly. "The federal government owns this entire road."

Something, though, was glaringly out of place on Aug. 24.

Three massive irrigation gates built into the steel border wall fence were open for anyone to walk through.

On the Mexican side of the border wall, fresh water bottles lay on the ground, covered in dew. Someone had also left origami puppets with the words "Peace" and notes in Spanish and English in plastic zip-lock bags.

"Look with compassion on the whole human family; take away the arrogance and hatred which infect our hearts; break down the walls that separate us," the note read.

Humanitarians leave water bottles, food for the illegals, and even children's toys to pick up as they cross into the United States through the open gates, says Sam, the pseudonym he uses to protect his identity.

"There's another open gate "bigger than this one, down that way," he says, pointing up the easement. "There are five or six gates like this"—all open.