I replied thusly in the comments:
This would be a good place to use the graffiti blaster on loan from Stripco to the city to prep for the Super Bowl. Read about it in this report by DMN city hall reporter Steve Thompson.
Until recently, graffiti cleanup by the city has primarily been the responsibility of one man: Dwight Jessie, a city employee who has done the best he can with few resources. He tries to match the paint color to the wall. He works weekends when volunteer groups offer to help paint.
Here's an idea: Let somebody paint the whole thing as a mural. If it's any good, the taggers will (mostly) leave it alone. It's not like the retaining wall - or the blue paint POS coverup job - are all that attractive, either. Why not grant permission to fill the space with art? From the looks of it, in this case the tagging was more attractive than the cleanup.RELATED: Dallas' new graffiti 'czar' looking past criminal justice approaches.
Indeed, if you're looking for folks to paint the wall for free, the cops have long lists of local taggers (most of whom they can't catch), in many cases with extensive photographic portfolios of their work. Pick somebody who's work doesn't suck, lay out the ground rules (no obscenity or gang references), then offer to let them paint it for free. I guarantee if you made the offer, you'd get takers.