Okay, so check this out.  Ronen, an artist living in Germany, jams the sewage systems of his town of Jena by placing behind the bars and grates of the sewage canals, life size images of migrant workers and asylum seekers displaying their papers.  The effect is stunning.

He writes…

“The viewers like the police/border guard will be able to check the papers explore the bureaucracy. Through different examples in different sewage entrances they can learn about the different kinds of legal status of refugees and migrants in Jena and elsewhere. The installation functions like a museum of bureaucratic legal papers, which to some people mean the difference between life and death. But the display does not last. Rain and snow, cigarette buts and chewing gum, and the rubbish of the city erases these pictures and the display of different migrants showing their papers to the public from the cities sewage start to disappear, just like so many people who already have. But the papers, the evidence of the regime, that will are with protection, last and will stay in sewage as memory of the people who we have confronted only days before.”

You can (and should) learn more about the project here and here