Reverse-graffiti in South Africa

Following the example of artists like Paul "Moose" Curtis and Brazil's Alexandre Orion, Durban, South Africa–based artist Martin Pace and fellow art school grads have been doing "reverse graffiti" -- scrubbing away exhaust grime on motorway walls, often using high-pressure water and stencils, to make art -- as a way of both calling out filthy walls and doing legal street art.

Says Pace, “We have had council guys in police cars stop us in the middle of the day while we are working and asking us if we have been commissioned to do this and when we answered no, they gave us thumbs up and said keep doing what you are doing.”

One unexpected result: once pollution is selectively removed from walls by artists, authorities immediately paint over it -- apparently ashamed at the neglect it suggests -- making a fresh canvas for more traditional graffiti taggers.

Via Broken City Lab and The Center for Sustainable Practice in the Arts.